Utah-Colorado Commercial Tree Fruit 2012 Production Guide

A publication by Utah State University Extension and the Western Colorado Research Center, Colorado State University 2011 Utah-Colorado Tree Fruit Production Guide

Publication Coordinators and Editors Marion Murray (IPM Project Leader, USU Extension) Harold Larsen (Plant Pathologist, Western Colorado Research Center (emeritus))

Chapter Authors IPM Methods Marion Murray, Diane Alston (Entomologist, USU)

Special Pest Management Programs Marion Murray, Diane Alston

Insect and Mite Biology Marion Murray, Diane Alston

Disease Biology Harold Larsen, Ramesh Pokharel (Plant Pathologist, Western Colorado Research Center)

Pesticide Tables/Information and Crop Spray Management Recommendations Marion Murray, Diane Alston, Harold Larsen, Ramesh Pokharel

Orchard Floor and Weed Management Teryl Roper (Horticulturist and Chair, Plant, Soils, and Climate Department, USU), Marc Rowley (former USU M.S. graduate student), Brent Black (Fruit Specialist, USU Extension), Marion Murray

Plant Growth Regulation and Thinning Teryl Roper, Brent Black

Nutrition Ron Godin (Agronomist, Tri-River Area, CSU Extension), Grant Cardon (Soils Specialist, USU Extension)

Irrigation Brent Black, Robert Hill (Irrigation Specialist, USU Extension), Grant Cardon

Cold Effects on Fruit/Bud Phenology Harold Larsen

Contact Information: Utah State University IPM Program Western Colorado Research Center Dept. of Biology Colorado State University 5305 Old Main Hill 3168 B 1/2 Road Logan, UT 84322 Grand Junction, CO 81503-9621 435-797-0776 (970) 434-3264 utahpests.usu.edu/IPM www.colostate.edu/programs/wcrc/

Funding for this publication was provided through grants and donations from: Western Region IPM Center Colorado State University USDA NIFA Extension IPM Program Utah State University

IPM Table Of Contents Programs Special Chapter 1 - Integrated Pest Management Methods ...... 1 Monitoring Techniques and Supplies ...... 1 Thresholds For Treatment ...... 4 Biology

Determining Treatment Timing ...... 4 Pest Degree Day Calendar For Common Insects ...... 6 Disease Chapter 2 - Special Pest Management Programs ...... 9 Biology Mating Disruption ...... 9 GF-120 for Western Cherry Fruit Fly ...... 12 Codling Moth Virus ...... 12 Pesticide Birds and Bats for Pest Suppression ...... 14 Tables Fire Blight ...... 14

Chapter 3 - Insect and Mite Pest Biology and Monitoring ...... 17 Apple

Chapter 4 - Disease Biology and Monitoring ...... 25

Chapter 5 - Pesticide Tables ...... 41 Pear Restricted Entry and Pre-Harvest Intervals ...... 41 Pesticide Toxicity to Honeybees and Pollinators ...... 46

Insecticide Classes ...... 50 Cherry Fungicide Classes ...... 51 Spray Incompatibilities ...... 52

Chapter 6 - Pest Management Pesticide Recommendations ...... 53 Nectarine Peach, Apple Pest Phenology Table and Spray Tables ...... 53 Pear Pest Phenology Table and Spray Tables ...... 71 Cherry Pest Phenology Table and Spray Tables ...... 84 Peach/Nectarine Pest Phenology Table and Spray Tables ...... 99 Apricot Apricot Pest Phenology Table and Spray Tables ...... 114 Plum Pest Phenology Table and Spray Tables ...... 123

Chapter 7 - Orchard Floor and Weed Management ...... 131 Plum Cover Crops ...... 132 Rodent Mangement ...... 133 Herbicides Labeled for use in Utah and Colorado ...... 137 Orchard Floor Chapter 8 - Plant Growth Regulators and Thinning ...... 141 Naturally Occurring Plant Hormones ...... 141

Thinning Apple Fruit ...... 143 Thinning Thinning Stone Fruit ...... 145 PGR Controlling Apple Tree Vigor ...... 145 Improving Fruit Quality ...... 146 Managing Fruit Maturity and Abscission ...... 146 Nutrition

Chapter 9 - Nutrition ...... 149 Nutrient Spray Table ...... 151 Irrigation Chapter 10 - Irrigation Scheduling ...... 153

Chapter 11 - Cold Effects on Fruit/Bud Phenology ...... 159 Evaluating Tree Fruit Bud & Fruit Damage From Cold ...... 159 Effects Growth Stages and Critical Temperatures ...... 164 Cold

Chapter 12 - Pesticide Information ...... 171

Pesticide Regulation, Safety, and Storage ...... 171 Information Pesticide Pesticide Use ...... 174 Understanding the Pesticide Label ...... 176 Chapter 1: IPM Methods IPM

Chapter 1 Integrated pest management Methods

Integrated pest management (IPM) involves collect- better. Also include trees from the following areas: ing information about a pest and crop to ensure that you administer the most economical, effective, and environmentally and socially sound pest manage- • known hotspots ment decision. IPM integrates as many suitable pest • where topography or soil type differs management options as possible. significantly • orchard borders The components of IPM are: How to Monitor 1. Examine each tree for overall health and for insect cycle) or disease activity. On leaves, look for chewing in- 1. Knowledge of pest (identification, biology, life 2. Monitoring for pests and injury (see next sec- jury, spots, changes in color, or stippling. On fruit, tion) look for spots, dimples, and rot. On the stems and root collar, look for discoloration, oozing, cracking 3. Deciding whether to treat based on thresholds bark, and holes. Check to be sure the tree is not 4. Implementing a set of control tactics being over- or under-watered. 5. Record-keeping (scouting results, treatments applied, treatment results)  After this visual inspection, use a beating tray to perform a closer inspection for insects. A beat-

Monitoring Techniques and Supplies surface on which to observe insects. ing tray is a large (approximately 18” x 18”) flat Monitoring for insects and diseases and for plant or To use, hold the tray under a limb and strike the fruit injury is essential for effective pest manage- limb with a padded stick three times. Examine ment. Knowing which pests are active and when, the dislodged insects visually or with a hand optimizes pesticide treatments. Regular monitoring lens. provides information on:

• early warning of potential pest problems • which pest life stage is active • presence or absence of natural enemies • when to implement control measures • whether pest control actions are working How Often to Monitor From spring through early summer, monitor at least once per week, and then every other week thereafter TOP BOTTOM until late summer. Ideally, scouting should occur on the same day each week. Plan to spend up to an hour, depending on the orchard size, to do a thor- ough job. A beating tray can be made by cutting window screen framing Where to Monitor to size and covering the frame with white or light blue cloth using screen spline. Screw a 2-foot aluminum pipe to the top Walk sections of the selected block in a diagonal or and bottom of the screen to make a handle. The padded stick zigzag pattern. Randomly select trees, and include at is simply a strong stick (such as a broom handle) padded on one least four trees of each cultivar in a block of 10 acres end with a duct tape-wrapped cloth. in size. The more trees that can be inspected, the

Utah-Colorado Tree Fruit Production Guide 1 Chapter 1: IPM Methods IPM

• Use a hand lens in the range from 10x-30x the pest you are viewing, hold the lens ap- magnification to identify pests. To focus on proximately 1-2 inches above the specimen. You can either look down through the hand lens from above, or bring your eye directly to the hand lens.

Orange delta traps are easy to use, last several years, and are not as attractive to honeybees as white traps.

 species is to occur: Hang all traps before first flight of the target

• CM: hang by first pink of Red Delicious • PTB: hang in mid to late April • GPTB: hang at shuck fall (early to mid June) Using a hand lens greatly helps in identifying insects. Aphids,  Hang CM and PTB traps within the upper third for example, look very similar to campylomma nymphs, and are difficult to tell apart with the naked eye. of the tree canopy and GPTB in the lower third. Make sure the trap entrance is parallel to the prevailing wind and clear of twigs, leaves and codling moth, peach fruit (to prevent birds from hopping into trap). twig borer, and greater peachtree borer. 2. Use pheromone traps for  A minimum of two traps per species should be placed in each orchard. Orchards greater than  Many of the harmful tree fruit pests are moth 20 acres should have one trap every 10 acres. species. Female moths release a pheromone scent to attract males for mating, and the scent  Hang at least one trap on the edge and at least one near the center of the orchard to determine traps use lures loaded with a synthetic version is specific to each species or group. Pheromone if moths are immigrating from outside sources of the pheromone scent for the target insect. - They are placed on a sticky liner that slides into pected “hot spots” need additional traps. a triangular Delta trap. and/or overwintering within the orchard. Sus  -  Although slightly more expensive, orange Delta sistent moth catch (1-2 moths caught two nights traps are easier to use and last longer than Check traps every 1 - 2 days until the first con wing-style traps. and is used in insect phenology models (see the in a row). Record this date; it is called the biofix  Colorado should use: following section). Expected first trap catches Pheromone traps that every grower in Utah and for northern Utah and western Colorado: early May) • CM: full bloom of Red Delicious (late April – • Apples/pears: codling moth (CM) (PTB) and greater peachtree borer (GPTB) • Peach/nectarine/apricot: peach twig borer • PTB: early May – mid May • GPTB: late June – early July

2 Utah-Colorado Tree Fruit Production Guide Chapter 1: IPM Methods IPM

 - ber of moths, and then remove them from the After biofix, check traps weekly, record the num sticky liner. They can be removed using a twig

from the orchard floor.  Change pheromone lures based on manufactur- ammonium er’s recommendations and change sticky liners carbonate lure in a after debris has collected on the surface. yellow container

Essentials of pheromone lures and traps:

“wing-style.” We recommend the delta traps • Traps are sold as “large plastic delta” or for ease of use (sticky liners easily slide in and out) and durability (reusable for several Yellow sticky traps are used for cherry fruit fly. The ammonium years). Do not use white-colored traps, as carbonate lure makes the trap more attractive. these attract bees. Prices: lures range from $1.20 each (for 30-  Place traps on the southern side of trees to catch day) to $5.00 each (for long-life and specialty • the upper third of the tree canopy. Remove fruit, lures); Wing-style traps are approximately $2 the earliest emerging flies, at least 6 ft high, in each, and delta traps, $5.00. leaves, and twigs within 6 inches of the trap. Longevity: Delta traps last up to 5 years, wing-  A minimum of two traps should be placed in style traps last less than 1 season. Lures last • - 30-60 days, depending on the type purchased pected “hot spots” should be monitored sepa- (CM and PTB are available as “long life” lures). each orchard, in the border and interior. Sus rately.  Maintain and check traps weekly throughout the and do not use it for another species to avoid • Label your delta trap with the insect lure used fruit development period. Change traps every cross-contamination. 3 - 4 weeks or when they become covered with debris. used in conjunction with mating disruption; • Some lures (codling moth) are designed to be  see page 9 for more information.  RefillKeep aor record replace of ACtrap bait catches containers for each as needed.location within an orchard and for each orchard. - • Store lures in the freezer at all times until fectiveness. Properly stored lures last 2 years. deployment in the field or they will lose ef Pest Identification

there are resources to help you. for western cherry fruit fly. If you find a pest or damage that you are unsure of, 3. Use Pherocon AM yellow sticky traps with AC lure  Options in Utah: trap, and AC (ammonium carbonate) increases Fruit flies are attracted to the yellow color of the - the effectiveness. AC is purchased separately, nostic Lab ( ) at 5305 and sold in small containers or Ziploc pouches. 1. Send the specimen to the Utah Plant Pest Diag utahpests.usu.edu/uppdl They are attached to the yellow trap with a and a submission form, which is available online, Old Main Hill, Logan, UT 84322. The fee is $7, twist-tie or staple. must accompany the specimen.  Prices: traps are approximately $2 each, and ad- 2. Contact your local county extension agent (exten- ditional baits are $1 each. sion.usu.edu).  3. View online image gallery at green stage of fruit development. . Hang traps before flies are expected: yellow- utahpests.usu.edu/ htm/images Utah-Colorado Tree Fruit Production Guide 3 Chapter 1: IPM Methods IPM

Options in Colorado: Beers, et.al., Orchard Pest Management, a

1. Send specimens to Western Colorado Research resource book for the Pacific Northwest. Good 81503-9621 with detailed information. Center 3168 B 1/2 Road, Grand Junction, CO Fruit Grower. 1993. ISBN: 0-963065-3-9 Tree Fruit Pest Identification and Monitoring Cards Strand, L. 2005. 2. Send specimens to the main campus at Plant . University of California ANR. Diagnostic Clinic, E215 Plant Sciences Bldg., Colorado State University, Fort Collins, CO 80523- accompanied by a form. 1177. Sample fees range from $7-20 and must be Thresholds for Treatment plantclinic.agsci.colostate.edu Pest monitoring provides information on pest 970-491-6950, Retailers of Monitoring Supplies activity and population size. To decide if control is Gempler’s required, pest density must be related to the poten- Mt. Horeb, WI Bend, OR tial crop damage and balanced against the cost of Suterra treatment. If the cost of treatment is more than the gemplers.com suterra.com crop loss, do not treat. Activity of natural enemies 800-382-8473 866-326-6737 must also be considered when determining whether Great Lakes IPM Trece to treat. For pests like aphids or spider mites, Vestaburg, MI natural enemies can potentially keep these popula- 800-235-0285 Salinas, CA greatlakesipm.com trece.com threshold levels, see Pest Biology sections. 408-758-0205 tions below economic injury levels. For specific pest

Riverside, CA Determining Treatment Timing: ISCA Technologies (951) 686-5008 Using Degree Days and Insect iscatech.com Phenology Models

Pest Monitoring Toolkit Degree days (DD) are a measurement of heat units over time, calculated from daily maximum and mini- mum temperatures. Degree days are used to predict • 10x-30x magnification hand lens - insect life cycles, and in turn, time insecticide treat- • orange delta traps and codling moth, greater mone lures ments to those life cycles. Insects are exothermic peachtree borer, and/or peach twig borer phero (“cold-blooded”) and their body temperature and growth are affected by their surrounding tempera- • extra sticky liners for traps - ture. Every insect requires a consistent amount of monium carbonate lure • Pherocon AM yellow sticky traps plus external am heat accumulation to reach certain life stages, such

that heat accumulation. • beating tray and padded stick as egg hatch or adult flight. Degree days interpret plastic containers for collecting unknown speci- • vials of alcohol, tweezers, a small paintbrush, and Degree days are based on the rate of an insect’s mens. development at temperatures between an upper and lower limit. The minimum temperature at which • fieldAgnello, guides: A. et al. Tree Fruit Field Guide to Insect, Mite, and Disease Pests and Natural Enemies of developmental threshold”, or baseline. The maxi- insects first start to develop is called the “lower Eastern North America. Natural Resource, Agri- mum temperature at which insects stop developing is called the “upper developmental threshold,” or 1-933395-02-8 cutoff. The lower and upper thresholds vary among culture, and Engineering Service. 2006. ISBN:

4 Utah-Colorado Tree Fruit Production Guide Chapter 1: IPM Methods IPM

Models used in tree fruit pest management. Horizontal Cutoff - Calcu- Upper max Lower cumulat- lation Threshold Start ac Insect threshold threshold ing DD method max codling Upper 50 88 biofix single sine moth Lower TU RE peach twig Threshold 50 88 biofix single sine borer greater min min

peachtree 50 87 March 1 single sine T E MP ERA borer 24 hours 24 hours western cherry fruit 41 none March 1 single sine TIME fly walnut This diagram is a visual representation of degree days using 41 none March 1 single sine husk fly the sine wave method of calculation, with a horizontal cutoff. The area in black under the curve represents the number of pear psylla 41 none Jan. 1 double sine degree days that fall between a lower and upper threshold, European 51 none March 1 single sine for each 24-hour period. red mite oblique- banded 43 85 biofix single sine leafroller This calculation method is the simplest and least San Jose use codling 51 90 single sine precise. scale moth biofix

The sine wave method yields a more precise calcu- species, and have been determined for many tree lation. This method still uses the daily minimum, fruit pests. maximum, and baseline temperatures (lower thresh- old), but also incorporates the upper threshold into Entomologists have studied biological development the calculation. It is based on the assumption that over time (phenology) of several fruit insect pests, temperatures of a 24-hour day follow a sine wave discovering exact degree day values that correlate to curve. The number of degree days is then calculated key physiological events, such as egg hatch or adult as the area under this curve within the lower and upper temperature thresholds. insect phenology model. Insect models are useful flight. This predictive information is known as an in timing insecticide treatment because the entire Depending on the instrument, degree days can be life cycle (or key events) of the insect is known.

calculated from max/min values for 24 hours down the calculated value is added to the prior value, Calculating Degree Days to max/min values for a single minute. In all cases, In general, degree days can be calculated using a resulting in an accumulated number from a set simple formula for the average daily temperature, calculated from the daily maximum and minimum starting point. The set starting point can be a fixed temperatures, minus the baseline (lower develop- western Colorado) or an event such as the date of date (which would be March 1 in northern Utah and mental threshold): by using pheromone traps). For an average growing [(daily maximum temperature + daily minimum first moth flight, called biofix (which is determined - proximately 2500-3500 degree days (with a baseline season in northern Utah, areas will accumulate ap temperature)/2] – baseline temperature.

of 50˚F). For example, a day where the high is 72˚F and the Treatment timing is determined by “forecasting” low is 44˚F would accumulate 8 degree days using degree day values into the future for a given loca- 50˚F as the baseline:[(72 + 44)/2] – 50 = 8.

Utah-Colorado Tree Fruit Production Guide 5 Chapter 1: IPM Methods IPM

tion, using either forecasted daily highs and lows or 30-year average highs and lows. This information is • University Extension newsletters:utahpests.usu. only an approximation of a future event, but is highly ) provide accumulated USU IPM pest email advisories ( useful in planning. For example, according to the and forecasted degree days for a variety of sites edu/ipm/htm/advisories

codling moth model, adults start laying eggs at 75 email weekly. - across northern Utah, and are delivered via degree days after biofix and eggs start hatching at 220 degree days after biofix (which equates to treat The Western Colorado Research Center ment timing for the first cover). produces periodic FruitFacts (www.colostate. Where to get degree days There are a variety of ways to acquire degree days, fruitinfo), an email newsletter that provides edu/programs/wcrc/pubs/research_outreach/ from dataloggers, online calculators, or printed degree days, treatment timing, and other newsletters. information

degree days every few minutes and are highly ac- • Biophenometers are instruments that calculate curate. Many brands allow you to manually input ) is an online degree day cal- • Utah TRAPs (Timing Resource and Alert for Pests, the target pest’s upper and lower thresholds. climate.usu.edu/pest culator for a variety of locations in northern Utah.

Timeline of insect degree days/calendar date/plant phenology for key life stages of orchard insects. Dates are estimated for northern Utah/western Colorado and degree days are provided for a lower temperature threshold of 50, unless otherwise noted.

Degree Days, Date, or Insect or Mite Life stage Event/Activity Phenology Range adult adults find hosts April Box Elder Bug adult 2nd gen. nymphs full grown Aug - Sept adult most migration before overwintering Oct eggs egg hatch 1st pink of apple Campylomma nymphs time to monitor 1st gen. mid-April - early June Bug nymphs summer gen. nymphs active June - Sept adults adults active late-may - late Sept pre-emergence hang trap 100 - 150 adult moth emergence begins; get biofix 175 - 290 degree days post biofix: larvae egg hatch begins 220 - 250 adult 1st flight peak 325 - 581 larvae period of greatest egg hatch 340 - 640 Codling Moth larvae egg hatch ends 1st gen. 920 eggs egg laying begins 2nd gen. 1000 - 1050 larvae egg hatch begins 2nd gen. 1100 larvae max hatch period 2nd gen. 1320 - 1720 adult 2nd flight peak 1337 - 1977 larvae egg hatch ends 2nd gen. 2100 larvae egg hatch begins 3rd gen. 2160 European Red Mite eggs 1st egg hatch 100 - 168 (base 51) nymphs summer egg hatch 424 - 572

6 Utah-Colorado Tree Fruit Production Guide Chapter 1: IPM Methods IPM

Continued. Timeline of insect degree days/calendar date/plant phenology for key life stages of orchard insects. Dates are estimated for northern Utah/western Colorado and degree days are provided for a lower temperature threshold of 50, unless otherwise noted. Degree Days, Date, or Insect or Mite Life stage Event/Activity Phenology Range Flatheaded adult adult flight period June - Aug Appletree Borer pre-emergence hang trap 400 Greater adult moth emergence begins 575 - 650 Peachtree Borer adult moth flight period mid June - Oct eggs egg hatch ¼” green Green petal-fall - hardened nymphs start scouting Apple Aphid terminals nymphs population builds up late May - early June Green adult moth emergence begins early spring Fruitworm larvae hatching spring Green Peach Aphid nymphs eggs hatch pink - full bloom (base 39) adults adults move to new leaf growth early spring Leaf Blister Mites adults adults enter bud scales to overwinter Aug - Sept eggs egg laying 252 - 300 Lygus Bug nymphs egg hatch 371 (base 54) adult summer gen. adults begin 623 pre-emergence hang trap; get biofix May Obliquebanded larvae peak egg hatch 600 - 1000 Leafroller (base 43) adult 2nd gen. moth emergence begins 1480 - 1683 adult 2nd gen. flight peak 1784 - 2108 pre-emergence hang trap 300 - 330 adult moth emergence begins; get biofix 400 - 450 degree days post biofix: larvae 5-28% egg hatch; best time to treat 300 - 400 Peach Twig Borer adult 2nd gen. moth flight begins 900 - 1080 larvae 2nd gen. egg hatch; time to treat 1200 - 1360 adult 3rd gen. flight begins 1760 larvae 3rd gen. egg hatch; time to treat 2140 - 2340 adult adults active 0 - 49 egg 1st gen. egg laying 1 - 72 Pear Psylla larvae 1st gen. egg hatch 60 - 166 adult 1st hardshell stage observed 312 larvae 2nd gen. egg hatch 584 - 750 eggs look in terminals April adults/eggs adults emerge/ lay eggs early June Pear Sawfly larvae larvae feed June adults 2nd gen. adults emerge late July - Aug Prionus Root adults adult emergence July Borer adults active in summer months summer

Utah-Colorado Tree Fruit Production Guide 7 Chapter 1: IPM Methods IPM

Continued. Timeline of insect degree days/calendar date/plant phenology for key life stages of orchard insects. Dates are estimated for northern Utah/western Colorado and degree days are provided for a lower temperature threshold of 50, unless otherwise noted.

Degree Days, Date, or Insect or Mite Life stage Event/Activity Phenology Range pupae pupal development begins 564 adult adult emergence begins 1056 Root Weevil eggs 1st egg laying 1498 (base 40) adult first leaf feeding observed; apply treatment early summer larvae treat overwintering larvae late summer - early fall nymphs overwintering eggs start hatching 56 Rosy adults wingless adults active early bloom - late June Apple Aphid adults migrate to weed hosts late June - early July eggs adult female lays eggs for overwintering late summer - early fall Rust Mite adults adults active (decline in hot weather) 1st bloom - early fall pre-emergence hang trap 120 - 150 adult adult male emergence begins; get biofix 177 - 322 degree days post biofix: San Jose Scale crawlers crawlers begin hatching 300 - 413 crawlers treat crawlers 600 - 700 adult 2nd gen. flight peak 1426 - 1776 crawlers 2nd gen. crawlers emerge 1916 - 2104 Spider Mite (McDaniel’s, adult rapid reproduction in high heat mid to late summer Two-spotted) adult adult emergence begins early spring eggs egg-laying begins pink Western Tentiform eggs egg-laying peaks bloom Leafminer larvae first mines observed early - mid May 1st summer gen., followed by 2 more over- adult early June - late summer lapping generations Stink Bugs adult adult emergence period May - June adult adult emergence begins 1890 Walnut Husk Fly eggs egg-laying begins 2480 (base 41) larvae egg hatch begins 2700 pre-emergence hang trap 750 - 800 adult adult emergence begins; watch trap 900 - 950 Western Cherry treat when fruit develops first salmon Fruit Fly adult fruit color salmon blush blush (base 41) adult 3% of flies emerged 1060 adult last adult catch 3049 White Apple nymphs egg hatch first pink Leafhopper adult 2nd gen. egg hatch late July - early Aug nymphs & adults first observation above ground June - July Woolly first treatment if population was high last Apple Aphid nymphs & adults early - mid Jul year

8 Utah-Colorado Tree Fruit Production Guide Chapter 2: Special Pest Management Programs Programs Chapter 2 SPECIAL PEST MANAGEMENT PROGRAMS Special

Mating Disruption

Mating disruption (MD) is an alternative pest control option for codling moth, peach twig borer, and great-

many conventional growers utilize this technology er peachtree borer. Although MD is certified organic, mating disruption program is the same or less than a to increase profitability. The cost of an established spray program.

Under normal circumstances, male moths find scent (called a pheromone), that females exude. female moths for mating due to the species-specific Under MD, an orchard is saturated with that same female pheromone, “confusing” males and prevent-

ing them from finding females. Mating never occurs of MD use, the target pest population declines and or is significantly delayed. After several seasons Female moths emit a chemical blend (pheromone) that forms a insecticide sprays may be unnecessary. MD works plume. Male moths follow the plume to find their mates(top) . best in large areas, and expanding MD to cooperat- In the presence of mating disruption, the female moth’s plume ing, neighboring orchards will improve effectiveness. is mixed with the plumes of pheromone dispensers, which inhibits the male’s ability to find the female (bottom). The When starting a new MD program, it is important male may either fly randomly and not approach a moth at all (thin dotted line) or home in on a dispenser or even a female (thick dotted line). The idea is that mating is either delayed monitoring traps for at least one previous season to or prevented. to first know the initial pest population level. Use determine general pest levels, outside pest pressure,

one year to use the following spring always require a full spray program at the same and hot spots. The first two years of MD will almost time, to bring pest population levels down. application rate on the borders and at “hot spots” • for new mating disruption orchards, double the Mating disrupters are called “dispensers”. Most dis- of lowering the application rate (not on the bor- pensers target just one pest, and are applied by hand • as moth populations decline, there is the option ders) to save costs either by twisting, looping, clipping onto a branch, or attaching to a post. (Sprayable MD, though available, traps is essential to determine pest pressure and has not proven effective.) • monitoring the target pest using pheromone need for supplemental sprays

In general: Codling Moth Mating Disruption Codling moth mating disruption works best in large, in the orchard canopy (do not bunch many in • hang hand-applied dispensers singly, and evenly, contiguous areas of orchard or isolated locations. fewer locations) Mating disruption dispensers should be placed in - pensers remain attached even in high winds • choose sturdy branches for hanging so that dis the orchard at bloom. Ideally, a biofix (first moth hanging a pheromone trap in a nearby, non-mating (for one season of control) flight) for each orchard should be determined by • reapply a fresh batch of dispensers each spring disrupted site and checking it daily during and after

• store leftover dispensers in the freezer for up to Utah-Colorado Tree Fruit Production Guide 9 Chapter 2: Special Pest Management Programs

bloom until moths are caught two nights in a row. Greater Peachtree Borer Mating Disruption

Special supplemental sprays (see page 4). It is impossible Programs Greater peachtree borer mating disruption is The biofix date is used to determine the timing for

been historically using mating disruption due to the disruption dispensers should be placed in the to get an accurate biofix within an orchard that has low moth population. successful in orchards 1 acre or larger. Mating

orchard at or before first moth flight (usually Monitor codling moth using large plastic delta traps can be hung at the same time as peach twig around June 20 in northern Utah), or, dispensers with a sticky liner and lure (see page 2). High load borer dispensers. Mating disruption for this codling moth lures must be used because the high pest is so successful that after a few years, the concentration of pheromone in disrupted orchards moth population will decline to almost zero, and monitoring traps will not catch any moths. As a be used according to the following guidelines: result, some growers use peachtree borer MD only masks traps with the standard lures. Traps should every two to three years.

• hang traps at Red Delicious bloom - Monitor greater peachtree borer using large plastic • hang in upper third of tree canopy chard), plus traps in hot spots delta traps with a sticky liner and lure (see page • one trap/10 acres (minimum 2 traps per or moths, or keep a running tally for each genera- • check traps once/week, and count and remove 2). There are no specialized high load lures; only tion or since the last insecticide spray according to the following guidelines: standard lures are available. Traps should be used Peach Twig Borer Mating Disruption Peach twig borer mating disruption works best • hang trap in early June • hang in lower third of tree canopy large, contiguous areas of orchard. Mating disrup- orchard), plus traps in hot spots tion dispensers should be placed in the orchard • one trap/10 acres (minimum 2 traps per moths, or keep a running tally - • check traps once/week, and count and remove before biofix (around shuck split). Ideally, a biofix termined by hanging a pheromone trap in a nearby, Causes of Failure (first moth flight) for each orchard should be de non-mating disrupted site at petal fall, and checking it daily until moths are caught two nights in a row. codling moth or peach twig borer) • Using MD in a small area (less than 10 acres for

supplemental sprays (see page 4). It is impossible such as along borders or areas upwind of strong • Not increasing MD dispenser rates in “hot spots” The biofix date is used to determine the timing for prevailing winds been historically using mating disruption due to the to get an accurate biofix within an orchard that has low moth population. • Applying MD dispensers after biofix (first moth flight) Monitor peach twig borer using large plastic delta recommendations • Not applying MD dispensers according to labeled

are no specialized high load lures; only standard necessary traps with a sticky liner and lure (see page 2). There • Not applying supplemental insecticides when to the following guidelines: lures are available. Traps should be used according • Not monitoring for sudden increases in moth populations and/or fruit injury removing cull piles and bins) • hang traps at petal fall • Not maintaining sanitation practices (e.g., • hand in upper third of tree canopy orchard), plus traps in hot spots are not ideal for mating disruption because the • Using MD in newly planted orchards, which • one trap/10 acres (minimum 2 traps per pheromone quickly dissipates due to lack of moths, or keep a running tally for each foliage • check traps once/week, and count and remove generation or since the last insecticide spray

10 Utah-Colorado Tree Fruit Production Guide Chapter 2: Special Pest Management Programs

Characteristics of common mating disruption dispensers Programs Special Brand Type Rate Cost (approx) Effectiveness Notes

Codling Moth - Apple, Pear hand-applied $100/acre Isomate-CM Flex 200-400/ac very effective hang high in tree loops (at 400/ac rate) hand-applied Isomate-C Plus 400/acre $100/acre very effective hang high in tree twists hand-applied Cidetrak CM 200/acre $110/acre effective hang high in tree clips hand-applied somewhat Checkmate CM-XL 200/acre $100/acre hang high in tree clips effective

hang high on mounted posts or in Checkmate CM-O tree; requires addition of hand-applied aerosol device 1/acre $120/acre effective Puffer dispensers on outer rows; distributor will map where products will hang

Peach Twig Borer - Peach, Nectarine, Apricot

where summers are longer/hotter hand-applied Checkmate PT XL 200/acre $70/acre effective than normal, dispensers may run out of clips pheromone before the season’s end

hand-applied somewhat Isomate-PTB 200/acre $100/acre has not been fully evaluated in UT or CO twists effective Greater Peachtree Borer - Peach, Nectarine

hang dispensers in lower third of tree hand-applied canopy; no supplemental spray needed; Isomate-P 100/acre $40/acre very effective twists dispensers will last through a hotter than normal summer

Lure types for monitoring pests in mating disrupted orchards Threshold to Apply Lure name Longevity Notes Supplemental Spray Codling Moth - Apple, Pear

this lure should not catch any moths in a successful MD orchard; 1x lure (standard 30 or 60-days --- only use if you suspect MD failure; can use this lure in non-MD lure) site to get biofix

10x; Mega lure 21 days not determined this lure has a high load of pheromone

Trece CM-DA this lure captures males and females; trap catches will be higher 60 days 10 moths (cumulative) Combo than 10x lures

Trece DA 60 days not determined this lure only captures females; not recommended

Peach Twig Borer - Peach, Nectarine, Apricot

none has been determined, because it is not a high load lure, these traps should not catch 1x lure 30 or 60-days consider treating after a any moths in a successful MD orchard cumulative capture of 6 moths

Greater Peachtree Borer - Peach, Nectarine

because it is not a high load lure, these traps should not catch 1x lure 30 days 2 moths/trap/7 days (average) any moths in a successful MD orchard

Utah-Colorado Tree Fruit Production Guide 11 Chapter 2: Special Pest Management Programs

GF-120 for Western Cherry and can be applied up to the day of harvest. It works by killing the adults upon ingestion, not the larvae

Special Fruit Fly within the fruit. Programs

ingredient, spinosad, with an attractive molasses- GF-120 won’t provide 100% control if the GF-120 is an insecticide that combines the active neighboring farms or backyard trees. Use yellow like bait. Spinosad is the same ingredient that occurs orchard has heavy outside fruit fly pressure from sticky traps baited with ammonium acetate to monitor for pest population size. One application of much lower concentration and different formulation. in Success and Entrust, but in GF-120 it is used at a imidacloprid (Provado, generics) near harvest may

GF-120 is approved for use in organic production, be necessary to kill worms in the fruit for the first 1-2 years of a new GF-120 program.

Advantages of GF-120: widespread area • highly effective after 2 years of use in a

• applied with a four-wheeler, saving gas and time • cheaper than many conventional insecticides; the cost bait costs about $20/acre, including application low mammalian toxicity (organic) • safe on natural enemies, groundwater, and has

• thorough coverage is not necessary minimal personal protective equipment • application time is quick, easy, and only requires D1 or D2 nozzle (no core) Disadvantages of GF-120: sprays) to be effective alone • must use at least 2 years (with supplemental Swivel nozzle orchards is low body • must make sure pressure from neighboring

• must reapply every 7 days • must reapply after rain Codling Moth Virus 1/4 turn plug valve Apple and pear growers looking for an organic option to codling moth control should consider the

im Smith, Washington State Univ. Washington T im Smith, codling moth granulosis virus (CpGV). The virus GF-120 should be applied with an ultra low-volume sprayer that is naturally occurring, specific to codling moth, will produce large droplets. The droplets do not need to cover other invertebrates, amphibians, reptiles, birds, and and is noninfectious toward beneficial insects and the entire tree. A 10 to 15-gallon spray tank with auxiliary mammals. A single ounce of a CpGV suspension sprayer and 12 volt pump can be mounted onto a four-wheeler, can contain up to 3 trillion microencapsulated viral and sprayed on at a driving speed of about 6-7 mph. Swiveling nozzles (to account for different sized trees) are mounted on by codling moth larvae. Once inside the larval gut, either side, or a double swivel nozzle body can be used. Be- particles. To be effective, the virus must be ingested cause the product is thick and gooey, it should be mixed outside the virus multiplies, and after a few days, feeding the tank first such as in a five-gallon bucket with an electric drill.

stops and the larva dies. New viral particles ooze 12 Utah-Colorado Tree Fruit Production Guide Chapter 2: Special Pest Management Programs Programs

out of dead larvae, and spread to the surface of the adults, they can travel Special fruit, able to cause new infections in other larvae. great distances and may not remain in one Used alone, this biocontrol option gives only area long enough for an insecticide to be organic orchards, the CpGV virus should be used effective. moderate control (from 60% to 80% control). In or with mating disruption, or it can be used in alternatively with oil or Entrust (spinosad) and/ conventional orchards to reduce chemical inputs. roadsides, hedgerows, Treat open fields, drainage ditches, and Cyd-X and Carpovirusine are two brands available to other weedy areas. Utah and Colorado growers. Some options include:

• Cyd-X: (4 oz/acre, $300 for 1 quart; Grand Mesa at groworganic.com) discount in Eckert, CO, 970-234-3424, or online 1. Bait + insecticide: • wheat bran Nosema locustae • Carpovirusine: (6.8-13.5 oz/acre) + carbaryl or Some points to remember when using codling moth (a natural virus: grasshopper Grasshoppers molt 5 times to pathogen) reach the adult, winged stage. codling moth larvae are on the surface of the fruit that must be • thorough coverage is very important because for a very short amount of time consumed

afterward, use a lower rate at shorter intervals grasshoppers eat the bait as they are foraging • use the highest rate on the first application; • spread evenly through the habitat, for food

(every 7 days) prevent initial breakdown of the product by the • apply in late afternoon or on a cloudy day to • easy to apply, but expensive sun foraging insects • selectively kills only grasshoppers and other because the larvae are not killed immediately; if following wetting events (rain, sprinkler • some surface feeding damage (stings) may occur • must be reapplied frequently and immediately this type of injury is unacceptable, use granulosis irrigation)

virus for the first generation only • very effective option degradation of the virus 2. Dust (carbaryl): • store the product in a refrigerator to reduce for Bt or antibiotics • can be mixed with most other pesticides, except • easy to apply, but expensive reapplied frequently • does not readily adhere to foliage and must be entry interval • can be used up to the day of harvest; 4-hour re- countries, so growers should not overuse this • resistance to the virus has been reported in other 3. Sprays (malathion, carbaryl, diflubenzuron): product • less expensive • adheres to plant material grasshoppers eat foliage Grasshopper Control • malathion and carbaryl kill on contact, or when to kill • diflubenzuron must be ingested and is slower Springtime, while grasshoppers are still nymphs, is the best time for suppressing grasshopper Sometimes the state department of agriculture will subsidize or coordinate grasshopper spray is the key to success. When grasshoppers become programs in severe grasshopper years. USDA-APHIS populations. Treating as wide an area as possible

Utah-Colorado Tree Fruit Production Guide 13 Chapter 2: Special Pest Management Programs

is responsible for control programs on public lands. population is dwindling due to lack of nesting sites. When grasshoppers occur at high numbers, state

Special and federal aid may be available in planning and Programs Kestrels: Attach nesting boxes to tall poles or To attract birds of prey: Management Program. conducting a Cooperative Rangeland Grasshopper trees 10-20 feet above ground, away from human chances of nesting, but note that a pair may Birds and Bats for Pest Suppression activity. Install up to 1 per 5 acres to increase material (twigs, wood shavings) can help attract defend up to 250 acres. Adding a bit of nesting Some bird and bat species can be useful allies the birds. Monitor each box weekly and remove starling nests. Clean boxes each year.

in running a successful IPM program. They are Barn owls motivated, efficient, and cost effective pest predators. attract the best and hungriest vertebrate predators. keep old wooden barns; they will not nest in There are ways to manage or manipulate the farm to : To attract/keep birds on the farm, Some of the most common and hard-working small cavity trees or abandoned buildings. Owls may metal barns. Nest boxes can be used in place of birds for orchards are:

patrol up to 200 acres per nesting site. insects including grasshoppers; nest in boxes or • bluebirds – eat large numbers of a variety of cavities moths. Of the Utah bat species, the big brown bat is Bats are the only night flying predators that target the most common that is adaptable to farmland. An established colony feeds by the millions on larger • chickadees - eat more insects, including scale, than any other; nest in boxes or cavities aphids, and leafhoppers, per bird (up to 900/day) insects. The little brown bat (locally abundant) also overwintering codling moths by extending their • woodpeckers – feed on borers, bark beetles, and adapts to farmland, and feeds on flies (including long tongue into tight crevices; nest in cavities mosquitoes), moths, mayflies, beetles, and mosquitoes per hour. leafhoppers. A single little brown bat can catch 600 variety of places • wrens - grasshoppers, and others; nest in a Bat houses should be installed against buildings In orchards (particularly organic), birds such as where they stay warm at night. Bat houses can be purchased from many farm and garden supply shown to help regulate codling moth densities by juncos, flycatchers, swallows, and sparrows have feeding on diapausing larvae. A study of a California a newly installed house. catalogues. It may take several years for bats to find codling moth larvae by birds during the winter apple orchard showed up to 83% predation of Fire Blight larger orchards, maintain diverse habitats (border (Baumgartner 2000). To attract and keep birds in planting mixes, alternate row plantings), leave a few older apple trees or large dead limbs for cavity to invest the energy in prevention and managing Managing fire blight is a year-round task. It is best nesters, and provide water and nesting boxes. light infections than doing nothing and dealing with severe infections that often result in tree or orchard Birds of prey feed on small mammals (mice, voles, removals.

is an excellent predator for mouse control. Kestrels Winter gophers) and birds. The kestrel is a small hawk that will return to boxes year after year, but are highly territorial. Barn owls (found in limited numbers out infested plant tissue will reduce the amount of The bacteria overwinter in cankers, and pruning in Utah) feed on large rodents and birds, and their inoculum in the orchard, thereby reducing future infections. Pruning should be done in winter and of great value in all agricultural situations, but their early spring when the weather is dry. Infected number one choice of prey is gophers. They can be

14 Utah-Colorado Tree Fruit Production Guide Chapter 2: Special Pest Management Programs Programs

twigs are easy to identify because the leaves will accelerated bacterial division occurs between Special remain attached well into winter. Limbs with bark that appears wet, off-color, or sunken indicate a cooler conditions if there is a recent history of 78 and 90° F. Infection may occur during slightly a 4-day accumulation of values related to each canker. Cut the twig or branch at least 8 inches blight infections in the orchard. The model uses not need to be sterilized between cuts. Debris does below the visible margin of the infection. Tools do day’s maximum temperature to determine risk suckers and rootstock sprouts at this time during caution, high risk, or extreme risk. not need to be burned or chipped. Remove all root potential. The 4-day tally may equate to low risk, regular pruning practices. If they become infected, they may put the entire tree at risk. Common 3. Moisture with bacteria, infection will not occur without : Even if flower stigmas are colonized susceptible to blight. dwarfing rootstocks such as M9 and M26 are highly Spring sufficient moisture to wash the bacteria into the floral cup. The Cougarblight model provides a Copper is limited to delayed dormant applications does not tell whether there is moisture in the risk of infection if the flowers are wetted, but (swollen bud to green tip stage). Its effect is orchard. It is up to the grower to decide on the dependent on how it is applied and the weather after presence of moisture. Wetting that triggers application. Copper works by providing a surface barrier that prevents bacteria from colonizing. As rain, dew, or misting or light wetting from flower infection may come from 2 hours of a result, copper must be applied as a high volume irrigation. Heavy rain or irrigation water that spray so that all exposed surfaces in the orchard directly strikes the blossom does not seem to are thoroughly wetted, including any tree cultivar trigger infection, perhaps because the blossoms are actually washed relatively free of bacteria are growing near susceptible trees, as well as all colonies. considered to be resistant (e.g., Red Delicious) that however, only last a few weeks, and the period of the Antibiotics should only be used on open blossoms. orchard support structures. The copper residues, to pink) is sometimes more than 2 weeks after green example on shoot blight or existing cankers). greatest spread of fire blight bacteria (tight cluster They are not effective at any other time (for tip. Whether a grower uses copper or not will Streptomycin (Agri-Mycin) is the most effective depend on weather, cost, amount of infection in the orchard, and personal experience. fire blight antibiotic available, but in Utah County, limiting its use. Currently, the only other alternative Utah, fire blight bacteria have developed resistance, Antibiotics are applied in spring during bloom, antibiotic is oxytetracycline (Mycoshield). only when the predictive model, Cougarblight, recommends. Cougarblight uses daily temperatures Streptomycin is effective because it has slight to provide a risk rating for potential infections. blight bacteria. It can be applied up to 24 hours systemic activity, lasts 3-4 days, and kills the fire before or after a wetting event. Adding the nonionic Utah orchards can access the fire blight model on the USU Climate Center website at: climate.usu.edu/ and uptake of streptomycin. In areas of documented TRAPs. The model is based on several factors: spreader-activator Regulaid will improve coverage Local blight history of the orchard resistance, streptomycin can be used once per presence or absence of blight in the orchard or season, and it must be mixed with oxytetracycline 1. : The nearby will affect the risk potential for infection. on that one use. So it should be saved for the “most important” spray where it will be the most blight in the orchard or in neighboring orchards effective. In areas where there is no resistance, it Infection is most likely to occur if there was fire last year. is recommended to use streptomycin only when necessary, and mix it with oxytetracycline to avoid 2. Daily maximum temperature: Although resistance.

bacteria can start multiplying at 50° F, the most Utah-Colorado Tree Fruit Production Guide 15 Chapter 2: Special Pest Management Programs

Oxytetracycline is not as effective as strep because control. Apogee-treated shoots have hard cell it works by slowing down the division of bacteria walls, physically barring the spread and growth of

Special rather than killing it. As such, it works best if Programs

fire blight, reducing build up during the summer. history. Where infections are high and antibiotics applied 12-24 hours before a wetting event to target The decision to use Apogee is based on past blight Oxytet lasts about 3 days. and pruning are not proving effective, Apogee can the bacteria before it is washed into the floral cup. It is important to realize that all trees can have late is that the rate of Apogee that is required stops new help to lessen the spread within trees. The drawback blooms during periods when temperatures are growth and applications may slow development and warmer, resulting in a great risk for infection. As result in reduced fruit size and return bloom. long as forecasts predict a high risk and blooms are open, antibiotics may need to be reapplied for Information on Apogee for fire blight Cost Rate Timing Notes protection if there is 2+ hours of moisture. Some organic growers are experimenting with $40-60 18-36 oz late bloom follow up 3-4 the use of biologicals with their antibiotic spray per per acre or early weeks later acre in 300 petal fall on very vig- program. Biologicals alone have not shown to be gal with orous trees; Regulaid takes almost of streptomycin resistance, biologicals can help 2 weeks for very effective in managing fire blight, but in areas the first ap- oxytetracycline be more effective. For best effect, plication to follow these guidelines when using biologicals: take effect

Pruning new infections in summer is just as must be wet for the biological to get started. • Increase water volume to 200 gal/acre. Trees important as pruning old infections in winter. Early

• Apply the material when flowers are about 15- in the tree. Young orchards are most sensitive and detection and removal slows the spread of fire blight 30% open (early bloom). A second application should be given high priority. If crews can catch can be made when flowers are 75-100% open. • Apply in early morning when temperatures are ineffective and will die. Biologicals need to blossom strikes just as they begin (i.e., the leaves/ are in the low 60s. Below 50, the biologicals amount to remove should be double the length of flowers are just starting to turn color and wilt), the the visibly damaged shoot tissue. If the infection have had a chance. A warm day after application colonize the flower before the fire blight bacteria is perfect. After successful colonization, it is OK if the weather turns cold. is older, find the edge of the canker and then prune not necessary to disinfect pruning tools between 12” beyond that. Prune only in dry weather. It is cuts so long as proper cuts are made (below, and not • Do not mix other pesticides with biologicals. through, cankers). Pruning debris can be left on the follow with an antibiotic when risk levels are • Continue to watch the Cougarblight model and hot and dry. orchard floor to be mowed, so long as the weather is high and 2+ hours of moisture is expected. When biological application, and with oxytetracycline, following with streptomycin, wait 1 day after Where infections are more severe and older wood wait 2 days after biological application. is affected, it is often best to wait until winter to do

• Do not apply biologicals after fruit set. a thorough pruning. Research has shown that heavy Summer actually increase the spread within the tree. pruning of fire blight during the growing season can calcium) can be used to manage shoot blight The growth regulator Apogee (prohexadione (but not blossom blight). Apogee does not affect Reference: the pathogen directly, and is not a substitute for Baumgartner, JoAnn. 2001. Birds, Spiders Naturally Control streptomycin during bloom for blossom blight Codling Moths. Tree Fruit Magazine, April 2001. pp 5-7.

16 Utah-Colorado Tree Fruit Production Guide Chapter 3: Insect and Mite Biology

Chapter 3 insect and mite biology and Monitoring

Aphids - Green Apple Aphid Aphids - Woolly Apple Aphid Biology HOSTS: apple HOSTS: apple Pest BIOLOGY: Overwinter as eggs in protected areas on BIOLOGY: Over- limbs and start hatching at half-inch green. Green winter as apple aphids remain on apples all season. nymphs pri- SYMPTOMS: Curled leaves; honeydew. marily on the MONITORING: Look for shiny black eggs in early roots, but spring. If aphids are a problem later in the season, sometimes start after petal fall and select a random shoot in cracks and on the major cultivar in the block and count the crevices in the tree canopy. Cottony colonies are number of leaves that have one or more wingless visible by mid to late June. Their waxy coverings aphids; repeat on 10-20 more shoots, and determine an average number leaves/shoot that SYMPTOMS: Galls at feeding sites (twigs and roots); make them difficult to control. have aphids. heavy feeding can reduce tree vigor; sticky colonies TREATMENT THRESHOLD: Delayed dormant oil will are messy during harvest. usually take care of this aphid. Otherwise, 4+ MONITORING: Start monitoring for colonies in mid- leaves/shoot infested with aphids during the June by checking root suckers and edges of pruning season will require treatment. cuts and wounds. DEGREE DAY MODEL: none TREATMENT THRESHOLD: No threshold determined. MGMT CONSIDERATIONS DEGREE DAY MODEL: none including lady beetle adults and larvae, lacewing MGMT CONSIDERATIONS: If colonies are present, : Numerous beneficial insects an insecticide treatment can be applied in early populations. to mid-July. If using spirotetramat (Ultor), apply larvae, and syrphid fly larvae help suppress aphid at petal fall to allow time for translocation of the Aphids - Rosy Apple Aphid chemical within the tree. HOSTS: apple BIOLOGY: Overwinter as eggs in protected areas on Aphids - Green Peach Aphid limbs and start hatching at half-inch green. Migrate HOSTS: apricot, to alternate weed hosts during summer. nectarine, peach SYMPTOMS: Curled leaves; honeydew; saliva of rosy BIOLOGY: Overwinter apple aphid is toxic to fruit cells, resulting in as eggs at the deformed fruit. base of buds in MONITORING: Look for shiny black eggs in early peach/nectarine spring. Starting at open cluster stage, examine at trees. Migrate to least 10 trees, spending 3 minutes/tree, and look alternate hosts for colonies. during summer. TREATMENT THRESHOLD: Delayed dormant oil will SYMPTOMS: Curled leaves; honeydew; feeding on usually take care of this aphid. Otherwise, an nectarine fruit results in deformities. average of more than one colony per tree may MONITORING: Beginning at petal fall, inspect the result in fruit injury. undersides of leaves for new colonies. For faster DEGREE DAY MODEL: none inspection, shake limbs over a cloth tray (“beating MGMT CONSIDERATIONS tray”) to observe the dislodged insects. including lady beetle adults and larvae, lacewing TREATMENT THRESHOLD: Treat peaches with 2+ : Numerous beneficial insects colonies/tree before shuck split or 6+ colonies/tree populations. after shuck split; treat nectarines at 1 colony/tree larvae, and syrphid fly larvae help suppress aphid at any time.

Utah-Colorado Tree Fruit Production Guide 17 Chapter 3: Insect and Mite Biology

DEGREE DAY MODEL: upper threshold: 82°F; lower Cat-facing Insects threshold: 39°F; 274 degree days required for one BIOLOGY: Overwinter generation. as adults and move MGMT CONSIDERATIONS to fruit trees when including lady beetle, lacewing larvae, and syrphid : Numerous beneficial insects Pest Pest crops or weeds) is Biology other food (field not as abundant. fly larvae help suppress aphid populations. Aphids - Black Cherry Aphid Feed with HOSTS: cherry piercing-sucking BIOLOGY: Overwinter mouthparts. as eggs on twigs SYMPTOMS: Deep pits and fruit spurs; in fruit; water-soaked gumming on peach fruit; hatch just before brown spots in tissue of apples. bloom. Migrate MONITORING: Use sweep nets in weedy areas or to mustard family orchard borders; inspect fruit for damage. weed hosts during TREATMENT THRESHOLD: No threshold determined. summer. DEGREE DAY MODEL: none SYMPTOMS: Curled leaves; honeydew. MGMT CONSIDERATIONS: Early-season feeding causes MONITORING: Look for shiny black eggs in early fruit distortion. Injury near harvest causes pits and spring at the base of buds. sunken areas on fruits and lowers fruit quality and TREATMENT THRESHOLD: No threshold determined. storability. DEGREE DAY MODEL: none MGMT CONSIDERATIONS: Delayed dormant oil Codling Moth will usually take care of this aphid. Numerous HOSTS: apple, pear BIOLOGY: Overwinter beneficial insects including lady beetle adults and as diapausing suppress aphid populations. larvae, lacewing larvae, and syrphid fly larvae help larvae, and pupate in spring. Adult Apple Maggot female moths lay HOSTS: apple eggs on and near BIOLOGY: Adults apple/pear fruit lay eggs in apples and larvae tunnel within fruit and feed on the or cherries in seeds. Two-three generations/season. summer; maggots SYMPTOMS: Frass at entry/exit hole; tunneling inside drop to pupate in fruit toward seeds. soil. MONITORING: SYMPTOMS: Knobby apples with cone-shaped pits; a) non-mating disruption: Hang pheromone trap

MONITORING or 100 degree days after March 1 to record narrow brown tunnels in apple flesh. Colorado Springs to Loveland, CO but has not been with regular codling moth lure at first pink : This fly is found in apples from trapped in commercial orchards in Colorado or moths have been caught). Leave trap in orchard date of first moth flight (called biofix, when 2+ Utah. To monitor, hang red sticky sphere traps and check moth numbers weekly to monitor starting in early July or at orchard borders. population throughout the season. TREATMENT THRESHOLD: According to Cornell b) mating disruption: Hang pheromone trap with

DEGREE DAY MODEL: lower threshold: 44°F; adults after March 1 in backyard tree or non-mating University, treat when 5 flies per trap are caught. CM-DA lure at first pink or 100 degree days active at 1450 degree days after March 1. disrupted area close to orchard to determine MGMT CONSIDERATIONS: This pest is regulated by a quarantine to prevent its spread. threshold level. biofix date. Continue checking trap weekly for

18 Utah-Colorado Tree Fruit Production Guide Chapter 3: Insect and Mite Biology

TREATMENT THRESHOLD: Utah). This insect is usually only a problem on a) non-mating disruption: no threshold; usually stressed trees (drought, wounding, etc.) or when treatment is needed throughout the season to populations are high in an area. All fruit tree vari- protect fruit. eties are susceptible. Biology

b) mating disruption: treat when 10 moths have SYMPTOMS: Oval-shaped exit holes; frass; loose, dead Pest been trapped using the CM-DA lures. bark. The larvae can eventually girdle trunks which DEGREE DAY MODEL: upper threshold: 88°F; lower will kill young trees and trees with multiple attacks. threshold: 50°F MONITORING: Watch for adult beetles May-July. TREATMENT THRESHOLD: No threshold determined. Event Degree Days DEGREE DAY MODEL: none 1% egg hatch (1st gen) 220 MGMT CONSIDERATIONS: The key to management is period of greatest egg hatch 340-640 to maintain healthy trees. Preventive trunk sprays 100% egg hatch (1st gen) 920 may be necessary to kill hatching larvae. 1% egg hatch (2nd gen) 1100 period of greatest egg hatch 1320-1720 Greater Peachtree (Crown) Borer 100% egg hatch (2nd gen) 2100 HOSTS: apricot, 1% egg hatch (3rd gen) 2160 nectarine, MGMT CONSIDERATIONS: Proper timing of insecticides peach is important. Utah offers spray timing dates at BIOLOGY: Adult www.utahpests.usu.edu/ipm/htm/advisories/ clearwing treefruit and Colorado offers information at: www. moths begin colostate.edu/programs/wcrc/pubs/research_ activity in outreach/fruitinfo. In addition, maintain proper late June and sanitation by removing apple bins from the orchard females lay and removing/mowing fallen fruit. their eggs on the base of tree trunks (apricot, peach/nectarine, Earwigs plum) or on upper roots through September. Young HOSTS: all fruit trees; cause damage to peach, apricot or stressed trees can be killed. BIOLOGY: European earwigs overwinter as adults SYMPTOMS: Tree decline or dieback; oozing gummosis and females lay eggs in the soil in early spring. mixed with frass at the soil-line of the tree. Populations become noticeable by mid to late June. MONITORING: Look for holes near the soil line and Wet, cool springs and summers favor this nocturnal oozing gum mixed with frass. To determine when insect. adults emerge, hang pheromone traps starting SYMPTOMS: Small holes in fruit and leaves with black in mid June or 400 degree days after March 1. dots of frass. Leave traps up and check weekly to monitor pest MONITORING: Corrugated cardboard “rolls” tied onto population throughout the season. the tree trunk can indicate when earwigs start TREATMENT THRESHOLD: If peak trap catch is greater climbing into trees. than 10/week, treatment may be needed, especially TREATMENT THRESHOLD: No threshold determined. : none case per tree. For greater peachtree borer under DEGREE DAY MODEL if you find an average of more than 1 empty pupal MGMT CONSIDERATIONS: Earwigs are also predators mating disruption: average of 3 moths/trap. on other insects, so their presence at times other DEGREE DAY MODEL: upper threshold: 87°F; lower threshold: 50°F

than when fruits are ripe can be beneficial. Event Degree Days Flatheaded Apple-Tree Borer adults begin flight (UT) 575-650 HOSTS: all fruit trees 50% moths have flown 1290 BIOLOGY: Overwinter as larvae inside tree, and emerge as adult beetles in June-August (northern MGMT CONSIDERATIONS: Peachtree borer can be

difficult to control because of the protection given Utah-Colorado Tree Fruit Production Guide 19 Chapter 3: Insect and Mite Biology

them once they have entered the tree. Mating TREATMENT THRESHOLD: No fruit injury occurs even disruption (1+ acres) or preventive trunk sprays in heavy feeding, so treatment early in the season covering the upper roots and 12-18” of lower trunk is done to prevent a nuisance population during are the main control tactic. picking. An average of 3 nymphs/leaf may require treatment, but trees can tolerate a much higher

Pest Pest density. Biology Leaf Blister Mites HOSTS: apple, pear DEGREE DAY MODEL: none BIOLOGY: Pear-leaf and apple-leaf blister mites are MGMT CONSIDERATIONS: Nymphs are easier to control microscopic mites in the eriophyid group. Adults than adults. overwinter under leaf bud scales and emerge with new leaf growth in the spring. They migrate to Leafrollers leaves and feed in colonies inside tiny blister-galls. HOSTS: all fruit trees SYMPTOMS: Newly formed leaf blisters are green and BIOLOGY: Leafrollers (obliquebanded, fruittree) then turn brown as the leaves age. are minor pests of all fruit trees. Depending on MONITORING: Watch leaves for blisters. the species, they overwinter as pupae or eggs TREATMENT THRESHOLD: High populations can and emerge in spring. Only the obliquebanded reduce photosynthesis and thus tree vigor. Lower leafroller has more than one generation. populations can be tolerated. SYMPTOMS: Rolled, chewed leaves; dimpling or DEGREE DAY MODEL: none scarring on fruit. MGMT CONSIDERATIONS: Cannot be treated in MONITORING: Look for rolled leaves at shoot summer. Horticultural oil or sulfur in fall or spring terminals starting in late May. is most effective. TREATMENT THRESHOLD: No threshold determined. DEGREE DAY MODEL: Obliquebanded leafroller has a Leafhoppers model but because it is such a minor pest, it is not HOSTS: apple, used. cherry MGMT CONSIDERATIONS: Leafroller populations are BIOLOGY: White suppressed by insecticides applied for control of apple and rose codling moth.

pests on apple Peach Silver Mite leafhopper are and tart cherry. HOSTS: nectarine, peach Nymphs begin BIOLOGY: These are microscopic mites called feeding on eriophyid mites, related to blister and rust mites. leaves by petal They overwinter as females within the tree and fall. They are move to leaves after budbreak. white and SYMPTOMS: Heavy feeding causes “silvering” of leaves, immobile (rose reduced fruit size, and premature fruit drop. MONITORING: Because these mites are so small, have black leafhoppers spots). The they are difficult to see with a hand lens, which adults are wedge-shaped with wings meeting in mid summer, check the leaves for the silvering makes monitoring for the mites difficult. Starting in a sharp peak over the back. There are two symptom. generations per year. TREATMENT THRESHOLD: No threshold determined. SYMPTOMS: White stippling on leaves; droppings (tar- DEGREE DAY MODEL: none MGMT CONSIDERATIONS: Moderate populations are during picking. a good food source for predatory mites, especially like spots) on fruit; flying adults are a nuisance MONITORING: Look for nymphs at petal fall on early in the season. undersides of leaves or by shaking branches over a cloth tray.

20 Utah-Colorado Tree Fruit Production Guide Chapter 3: Insect and Mite Biology

Peach Twig Borer Pear Psylla HOSTS: apricot, HOSTS: pear nectarine, peach BIOLOGY: Overwinter BIOLOGY: In spring, as adults outside Biology the brown larvae the orchard and Pest emerge from move in to lay overwintering eggs on buds and cells on the twigs in early limbs of trees, spring. The adults and tunnel into resemble small succulent leaf cicadas. shoot tips where SYMPTOMS: Honeydew; leaf scorching; leaf drop; black they soon pupate sooty mold on leaves and fruit. Pear psylla may to adults. Later also transmit a disease called “pear decline” that in the season can slowly kill trees over a number of years. (after shoot MONITORING: Look for psylla adults early in the growth hardens spring (starting 6 weeks before bloom) by tapping off), larvae enter peach/nectarine or apricot fruit or shaking the branches over a light colored beating as they soften. tray. SYMPTOMS: Infested twigs wilt and die back and small TREATMENT THRESHOLD: Early season, 0.5 nymphs/ masses of gum exude from tunnel openings; frass leaf; summer, 1.5 nymphs/leaf; examine 10 leaves on larval entries into fruit. per 5 randomly selected trees/block. MONITORING: DEGREE DAY MODEL: lower threshold: 41°F a) non-mating disruption: Hang pheromone trap MGMT CONSIDERATIONS: Root stocks resistant with peach twig borer lure at 300 degree days to pear decline are available. Resistance to many insecticides has occurred in pear psylla populations, so switching insecticides across years after March 1 to record date of first moth flight Leave trap in orchard and check moth numbers can help prevent resistance in your orchard. The (called biofix, when 2+ moths have been caught). weekly to monitor population throughout the best control is achieved with a dormant spray to kill season. overwintered adults before new eggs are laid. b) mating disruption: There are no special peach twig borer lures for monitoring orchards under Pear Sawfly (Pear or Cherry Slug) mating disruption; follow “a” above. HOSTS: cherry TREATMENT THRESHOLD: Usually treatment is always BIOLOGY needed throughout the season; no threshold has Adults lay eggs on leaves in mid summer. The : Overwinters as a sawfly pupa in the soil. been determined for peach twig borer under larvae have a slug-like appearance and feed on the conventional management or mating disruption. upper surface of the leaf epidermis. DEGREE DAY MODEL: upper threshold: 88°F; lower SYMPTOMS: They cause a skeletonizing injury where threshold: 50°F membranous “windows” of leaf tissue remain in between leaf veins. Event Degree Days MONITORING 5-28% egg hatch (1st gen) 300-400 to late July. 5-28% egg hatch (2nd gen) 1200-1360 : Watch for sawfly larvae starting in mid TREATMENT THRESHOLD: No threshold determined. MGMT CONSIDERATIONS: Proper timing of insecticides DEGREE DAY MODEL: none is important. Utah offers spray timing dates at MGMT CONSIDERATIONS: The larvae are often www.utahpests.usu.edu/ipm/htm/advisories/ suppressed by insecticides applied for other pests. treefruit and Colorado offers information at: www. Trees can tolerate low populations. colostate.edu/programs/wcrc/pubs/research_ outreach/fruitinfo.

Utah-Colorado Tree Fruit Production Guide 21 Chapter 3: Insect and Mite Biology

Root Borers Rust Mites HOSTS: cherry, HOSTS: apple, pear peach BIOLOGY: Rust mites are microscopic mites in the BIOLOGY: Prionus eriophyid group. Adults overwinter under leaf bud root borer (right) scales of pear and apple, and emerge with new leaf

Pest Pest and ten-lined growth in the spring. Biology June beetle grubs SYMPTOMS: Russeted fruit; pear leaves are sensitive feed on roots and to rust mites, becoming bronzed or with necrotic crowns of cherry lesions. Very high populations of rust mites can and peach. They reduce photosynthesis and thus tree vigor. can be a problem in sandy soils. MONITORING: Use a hand lens to inspect leaves SYMPTOMS: General tree decline with few other above starting in mid-spring. ground symptoms. Extensive feeding throughout TREATMENT THRESHOLD: No threshold determined. roots and within wood. DEGREE DAY MODEL: none MONITORING: Research is underway to develop a lure MGMT CONSIDERATIONS: In apple, rust mites can be for monitoring prionus beetle adults. TREATMENT THRESHOLD: No threshold determined. for predatory mites that also help suppress spider beneficial in that they may serve as alternative prey DEGREE DAY MODEL: none mites. In pear, lower populations can be tolerated. MGMT CONSIDERATIONS: Soil application of a systemic insecticide may be an effective treatment. Scale (San Jose Scale) Currently, imidacloprid (systemic) is only labeled HOSTS: apple, cherry on apple and pear. Check the insecticide label BIOLOGY: San Jose scale to be sure the fruit crop is listed before use. is an armored scale Entomopathogenic nematodes and fungi can be that overwinters as effective on June beetle larvae. a mix of nymphs and adults. Crawlers Root Weevils (newly hatched HOSTS: all fruit trees nymphs) BIOLOGY: The adults emerge in are very hard, late spring rounded beetles and a second with pronounced generation “snouts,” and are emerges in late primarily active summer. They at night. Adults feed on sap feed on foliage from leaves, and the small, white legless larvae feed on roots limbs, and fruits. and crowns. SYMPTOMS: Feeding on apple and pear fruit appears SYMPTOMS: Semi-circular notches at leaf edges. as red halos with white centers. Heavy feeding MONITORING: Check for leaf damage in summer. reduces tree vigor and blemishes fruit. TREATMENT THRESHOLD: No threshold determined. MONITORING: Look for limbs encrusted with small, DEGREE DAY MODEL: none circular, black and gray armored scales. Monitor for MGMT CONSIDERATIONS: The best timing for crawlers by wrapping black tape around an infested suppression is in the spring and early summer limb and covering the tape with petroleum jelly; look for trapped crawlers. There are pheromone in the late summer to early fall to target larvae traps for male adults but they are mostly unreliable. when leaf-notching injury first appears, and again before winter. Entomopathogenic nematodes and TREATMENT THRESHOLD: Treat at crawler stage if any fungi applied to the soil by the roots can kill larvae. fruit in the orchard in the prior season had scale. DEGREE DAY MODEL: upper threshold: 90°F;

22 Utah-Colorado Tree Fruit Production Guide Chapter 3: Insect and Mite Biology

lower threshold: 51°F; crawlers begin hatching horticultural mineral oil every 5-7 days until mite approximately 300-400 degree days after codling densities decline can be effective. Avoid applying soaps or oils during the hot part of the day as some MGMT CONSIDERATIONS leaf burn may result. moth biofix; time to treat is at 600 degree days Biology Dormant oil can kill a portion of overwintering Pest : Adults are difficult to kill. nymphs, but crawlers hatched from overwintering Spotted Wing Drosophila adults will have to be treated when they emerge. HOSTS: all fruits BIOLOGY: Spider Mites Overwinter HOSTS: all fruit trees as adults and BIOLOGY: Mites pupae, but it are very small is unknown arthropods that whether SWD can survive northern Utah winters. are more closely Adults lay eggs inside fruit and maggots feed on related to ticks pulp. than insects. SYMPTOMS: Sunken fruit; holes in fruit European red MONITORING: SWD was found in Davis County, UT, mites overwinter in 2010 and 2011 in very low numbers, but we as black eggs on tree limbs and, if abundant, can suspect reintroduction each year. Monitoring cause feeding injury early in the season. Two- should be done using traps containing a cider spotted and McDaniel spider mites overwinter as vinegar or sugar-yeast bait. See the USU factsheet, adults on lower trunks and in groundcover, and Spotted Wing Drosophila, for more detailed may become a problem during hot, dry conditions information on monitoring techniques. in the mid and late summer when they reproduce TREATMENT THRESHOLD: None determined yet. rapidly (1-2 weeks to complete a generation). DEGREE DAY MODEL: none SYMPTOMS: Stippling on leaves due to removal of MGMT CONSIDERATIONS: Monitoring will help to chlorophyll and sap; severe feeding causes “mite determine if this pest has been introduced to your area. becomes apparent when populations are high. burn.” Spider mites produce fine silk webbing that MONITORING: Before budbreak, look for European Thrips, Western Flower red mite egg masses on tree bark and near buds. In HOSTS: apple, nectarine late spring, watch for stippling damage on lowest BIOLOGY: Overwinter as adults in protected areas on the ground and emerge in spring and feed on and TREATMENT THRESHOLD: Start monitoring 5 weeks interior leaves first. Shake limbs over cloth tray. after bloom and treat if average number of mites also feed on young fruit, but are not a pest on lay eggs within, flower parts. Adults sometimes per leaf is greater than 10 (apple and cherry) or 5 apples after bloom. They may feed on older (pear). nectarine fruit, causing russeting. DEGREE DAY MODEL: none SYMPTOMS: Nectarine: scarring, russeting, MGMT CONSIDERATIONS: In addition to plant- deformation; Apple: “pansy spot” most visible on feeding mites, there are predatory mites that feed yellow varieties. on spider mites. Predatory mites can provide MONITORING effective biological control if they aren’t harmed cup or jar. Test 5 clusters on 5 trees per 10 acres. : Shake flower clusters vigorously into a by pesticides. Low populations of spider mites TREATMENT THRESHOLD: In yellow apple varieties, can be ignored and are often kept in check by treat if there is more than 2 adults per cluster. In the predatory mites. Spider mite outbreaks nectarine, treat if there is more than 1 adult per often follow pesticide applications that upset cluster. the predator-prey balance. Resistance to DEGREE DAY MODEL: none chemicals is common, so miticides should not be MGMT CONSIDERATIONS: Minute pirate bugs and used repeatedly. Applying insecticidal soap or lacewings are important predators late in the

Utah-Colorado Tree Fruit Production Guide 23 season to help reduce populations the following spring. Treat at petal fall for best control, after bees have been removed from the orchard.

Walnut Husk Fly HOSTS: apricot, nectarine, peach BIOLOGY: The

is a tephritid SYMPTOMS: Small walnut husk fly holes in fruit with apple maggot maggots inside. fruit fly like the and western MONITORING: Yellow stick traps baited The adults are with ammonium carbonate. cherry fruit fly. about the size of TREATMENT THRESHOLD: No threshold determined. DEGREE DAY MODEL: lower threshold: 41°F have patterned MGMT CONSIDERATIONS: To prevent egg-laying in a house fly and wings with an inverted “V” at the tip. It lays eggs in the husk of detected, when fruits develop a salmon blush color, fruits, treat by 5-7 days after the first flies are walnut after the husk has softened a bit. It will also or when 900 degree days has passed since March lay its eggs in softening peach and nectarine fruits, 1. Proper timing of insecticides is important. Utah offers spray timing dates at www.utahpests.usu. due to the presence of non-treated walnut trees. edu/ipm/htm/advisories/treefruit and Colorado especially where husk fly numbers are elevated Larvae (maggots) feed within fruits. offers information at: www.colostate.edu/ SYMPTOMS: Small maggots inside peach/nectarine or programs/wcrc/pubs/research_outreach/fruitinfo. apricot fruit. MONITORING: Yellow sticky traps baited with ammonium carbonate. TREATMENT THRESHOLD: No threshold determined. DEGREE DAY MODEL: none MGMT CONSIDERATIONS: Treat by 7-10 days after the

first adult flies are caught or beginning in late July. Western Cherry Fruit Fly HOSTS: cherry BIOLOGY are a common pest of cherries in northern and : Western cherry fruit fly larvae (maggots) central Utah. Every cherry can be infested by a maggot if populations are high. The dark banding

malformed letter “F” with the cross-bar originating pattern on the wings of the cherry fruit fly is a from the upper vertical bar rather than the upright bar.

24 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology

Chapter 4 Disease Biology and Monitoring

Apple Scab vety brown to olive green spots that become brown biology: Apple scab is caused by the fungus Venturia - inaequalis. It is an infrequent disease of apple in and corky with cracks often (but not always) ap Disease Colorado and Utah, but is more often encountered Biology in fruit growing areas with humid, cool weather pearing in the skin and flesh (Fig. 4.1). Late season during the spring months. It is prevalent in the theinfections fruit is may in storage. produce very small spots (known as eastern U.S. and requires application of more chem- pin-point scab) that may not become visible until icals for its control annually than any other disease. Monitoring: Infections require different lengths of - fective wetness periods depend on temperature. At 1990.In 1984, It hasit was since first spread observed to other in Utah areas (Utah and County) should 61-75oF,time of continuous only 6 hours leaf are wetness needed, for while success. at 48oF, The 12ef beand considered first observed a potential in Colorado problem (LaPlata in most County) northern in - Utah counties and other areas with wetter spring cide sprays need to be applied within 24 - 96 hours weather. It can cause serious economic fruit loss in hours are required. Postinfection (curative) fungi- commercial apple orchards if left untreated. Both primary and secondary infections are possible for tablefollowing of temperatures infection in orderand wetness to be effective. periods Thomneeded apple scab; control of primary infection is essential forson infection. & Ockey (see references) provide a simplified to manage disease severity within an orchard. In semi-arid regions like western Colorado and Utah, Management: Apple scab can be minimized by use of apple scab can be controlled through use of postin- scab-resistant apple cultivars and reduced by use of fection sprays using chemicals with “reach back” good orchard sanitation practices, but control usu- ally requires the use of a fungicide spray program. fungicides only on those rare occasions infection Some newer cultivars are more resistant to apple periodsefficacy. have This occurred.enables such growers to apply control - Disease Cycle ablescab; in the the best near of future. these at Elimination present include of diseased ‘Liberty’ body initials within infected leaves and fruit on the and ‘Prima’, but several others may become avail : The fungus overwinters as fruiting- ment of these initials and for primary spore pro- leaves and/or fruit on the orchard floor is good orchard floor. Moisture is required for develop acceleratinggeneral policy. the This rotting can processbe done through by raking application and of water is also needed for primary spore germina- burning, disking (in clean cultivated orchards), or- tionduction on the (ascospores) new leaves in and/or the spring; fruit. a A surface minimum film eas where winter temperatures are mild and mois- of 9 hours of continuous wetting are required tureof nitrogen is enough (e.g., to as at urea)least partiallyto the fallen rot theleaves leaves. in ar at 63-75°F for germination of primary spores Often, however, neither horticultural approach

temperatures and early in the season. Initial and secondary(ascospores). infections Longer quickly times are begin needed to produce at other the

conidia are the main means of disease spread dur- ingsecondary the summer spores months. (within 9 to 17 days), and these

Symptoms

: The most obvious symptomsPyracantha occur on andthe leaves mountain and ashfruit. all Domestic can be infected apples, by flowering V. inaequa - liscrabapples, hawthorn, firethorn ( spp.), green spots that look like dark mold on the leaf sur- face;. Leaf infected infections leaves consist become of deformedvelvety brown as the to infec olive- tions age and may appear curled, dwarfed, or other- wise distorted where numerous infections occur on Fig. 4.1. Red Delicious apple with apple scab infection lesions. young leaves. Fruit infections begin as similar vel- Note fruit crack running through one lesion.

Utah-Colorado Tree Fruit Production Guide 25 Chapter 4: Disease Biology

is effective on a commercial basis, and fungicide disease within a tree, although movement from tree sprays are needed. - op very slowly at 45°F; their development is much Correct timing is essential for good control; early to tree usually is somewhat slower. Lesions devel - season control of the primary infections greatly gus typically overwinters on infected dormant buds reduces secondary and pin-point scab infections. andfaster in atsmall optimal twig temperatures cankers. of 70-80°F. The fun

when the young apples are 12 mm in diameter is Symptoms: First symptoms of infection appear as theThe most period critical. between Either the startprotective of bud or growth post infection and small red spots on young leaves which enlarge eradicative spray materials or both can be used. Biology Disease Disease - tible tissue is exposed in the spring and every 7-10 leaveand become a “shothole.” purple Severe with a leaftan-white infections center produce (Fig. daysProtective throughout materials the areseason applied if scab as issoon present as suscep on numerous4.2). The spots holes then and dropgive the out affected of the leaf leaves blade a veryto tattered appearance. Shoot infections also appear postinfection approach requires accurate monitor- as reddened spots; these are helpful to differenti- theing ofleaves orchard or until temperatures all primary and spores the length are gone. of time The the leaves remain wet. Hourly observations pro- Necrotic Ringspot, which also induces red spots on vide the most accurate data for determining when ate Coryneum blight from the virus disease, Prunus an infection period has occurred, and periods of Fruitthe leaves infections (but not begin the as twigs). purple-red spots on the fruit skin as early as shuck-split and may occur as conditionsleaf wetness separate should bethem. added together (considered late as at harvest. Early infections when the fruit is as a single wet period) if less than 8 hours of dry and roughest, scab-like spots on the fruit skin. In severesmall generally cases, spots produce coalesce the andlargest cause (to the6 mm skin diam.) to presentlyMaterials usedinclude for Cyprex, preventative Funginex, sprays Nova, include and Ru- Captan and Cyprex. Postinfection chemical options

bigan. Their “reach-back” abilities range from 36 Referenhoursc (Cyprex)es: to 96 hours (Nova).

Thomson, S.V. and Ockey, S.C. 2000. Apple Scab. Utah Plantfactsheet/apple-scab00.pdf Disease Control No. 48. . Utah St. Univ. Coop. Ext., Logan. 3 pp. extension.usu.edu/files/publications/ Coryneum Blight (Shothole) biology: Coryneum blight, also called shothole, is a fungal disease of stone fruit trees including peach, nectarine, apricot, cherry and almond. It is caused by the fungus Wilsonomyces carpophilus Coryneum beijerinckii is most common on apricot, peach, and nectarine. Both(= leaves and fruit may). beIn Utahinfected; and severeColorado, leaf it infections with extensive shotholing may weaken a tree, while infections on the fruit produce the most apparent damage and economic loss.

Disease Cycle: Spore production begins in early spring and continues until fall. Rainy weather Fig. 4.2 (top). Coryneum blight lesions on sweet cherry spreads spores from infected twigs and leaves to leaves. uninfected twigs, young leaves, and developing fruit by splashed and wind-blown rain. Wet weather Fig. 4.3 (bottom left). Corky infections on peach. also favors infections because spores require 4 hrs Fig. 4.4 (bottom right). Late season coryneum blight infec- of contact with free water in order to germinate. tion on peach after 2 weeks in cold storage. Note the sunken Wet weather periods can lead to rapid spread of the lesions with localized rot.

26 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology

Disease Cycle: Leucostoma is a wound parasite – it when the fruit is larger generally produce smaller needs an injury to the bark to enter the tree. In- redcrack spots, and gumbut these (Fig. also4.3). reduce Mid-season fruit quality infections and jured cells at the entry point provide necessary food for the fungus spore to germinate and grow. harvest produce sunken, greyish lesions that ex- pandincrease and cullage. create sunken Late infections rot spots on during fruit nearingstorage pruning wounds, borer damage, spray injury, or otherThis entry wounding. may be About through 30 frostdays injuryafter infection to the bark, and Disease the start of canker formation, pimple-like fruiting Biology Monitoringand render: theDuring fruit pruning, non-marketable check overwintering (Fig. 4.4). twigs for dead buds with a darkened color and bark surface and a new crop of spores is ready a sunken darkened canker beginning to encircle forbodies release. (pycnidia) Spores have are exudedformed frombeneath the thetop infected of the them. During the growing season, check twigs and young leaves for small red spots. If spots are found on leaves, check closely on new twig surfaces fruiting bodies mixed with a polysaccharide (large for spots in order to verify that Coryneum is re- sugar) solution. The spore mass can take the form of rounded mounds (under humid conditions) or purple-red spots. singleeven irregularly spores by twistedwind, rain, threads insects, (under birds, more and dryon sponsible rather than PNRSV. Check fruit for small pruningconditions). implements The spores to other are spread trees. as groups or as Management: Fall applications of copper sprays or Bordeaux mixture are effective in controlling this Recent studies show that canker development can disease. Chlorothalonil sprays in fall and/or spring take place throughout the year. However, the great- before shuck fall also work well. est canker growth occurs in the spring on stone fruit as temperatures warm up and before tree ac- References: Evans, K., et. al. 2008. Coryneum or Shothole Blight. fruit, L. persoonii tivity resumes. The primary causal fungus on stoneL. pp. , grows best at 77–86°F (even up Utahcoryneum-blight08.pdf. Pests Fact Sheet PLP-008. USU Ext., Logan, UT. 3 cincta, grows at temperatures of 39–86°F with best extension.usu.edu/files/publications/factsheet/ growthto 99°F). at The 64–68°F. primary Extensive causal fungus gumming on apple,frequently Leucostoma (Cytospora) Canker shows up in early summer on stone fruit trees be- cause of rapid canker growth in the spring where (“Gummosis”) there were no symptoms of canker the previous fall. biology: Leucostoma - Also, studies indicate that active tree growth with woody tissue deposition and callus development canker (previously called cytos is destructive on peach, nectarine, plum, apricot, creates a barrier that can slow growth of the fun- cherry,pora canker and occasionally or “gummosis”) on apple. is a fungal Infections disease in that stone fruit trees quickly become severe, with scaf- fold branches or entire trees dying within 4-8 years Symptomsgus. The: Onfungus stone overwinters fruit, discolored as canker yellow infections. or amber gum indicates the presence of Leucostoma 1-2 years after infection if the trunk is the infection after initial infection (new trees may die within Leucostoma low-temperature, or other physiological injury, (Fig. at persoonii is more common in warmer fruit growing 4.5), while clearLeucostoma gum indicates frequently borer, mechanical, invades in- site). Two fungal species are involved: - cally infects through pruning wounds; L. cincta is least initially. ( areas (e.g., Utah and western Colorado) and typi beneathjured tissues the gum within are a brownish few weeks). in color, The innerbecoming bark tissues and cambium layer (wood/bark interface) - more common in cooler growing areas (e.g., higher to infect through damaged fruit buds. L. persoonii sion of the infection often occurs in spurts which elevation orchards in Utah & Colorado) and tends tends to be more common on peach, nectarine, aare dark evident brown in asalternating the infection bands progresses. of darker andProgres light- plum, apricot, and lower elevation cherry while L. cincta tends to be more common on apple and high- the bark as the spore-producing fruiting bodies er elevation cherry. Infections in apple are much er colored tissue (Fig. 4.6). Pimples appear beneath slower expanding, but can also lead to branch or tree death within 6-8 years. Substantial infections to(pycnidia) be exuded develop, through and the the opening bark eventually during and splits fol- throughout a stone fruit orchard can result in the above them to allow the spore masses (in mucilage) entire orchard becoming non-economic because of missing scaffolds and trees and being removed. shapedlowing extendedthreads. Aswet the periods infection . These progresses spore masses around can look like wet mounds (Fig. 4.7) to irregular

Utah-Colorado Tree Fruit Production Guide 27 Chapter 4: Disease Biology

the circumference of the branch or tree trunk, it girdles the structure and cuts off nutrient and wa-

whenter flow higher to the temperatures structures above and lowthe infectionhumidity andresult inthis a higherproduces demand dieback. for waterThis can in theoccur tree very branches rapidly with active foliage.

Symptoms in apples are similar but without the gum. Infections quickly result in a reddened color Biology Disease Disease to the bark surface with reddish-brown discolor- ation of the tissues beneath. Discoloration of the

similar to those seen in stone fruit develop beneath theinner bark tissues surface becomes as the darkerpycnidia with develop. time. PimplesSpore production typically results in irregularly shaped

the circumference of the infected branch eventually girdlesspore threads. the structure Progression and causes of the branch infection dieback. around Again, the dieback is most quickly noticed when trees are under drought stress.

Monitoring stone fruit trees with discolored gum oozing from branches and: Growers trunks shouldduring pruningwatch for and and during flag

stone fruit and apple trees with reddening bark on branchesthe growing and season. dieback. In Developmentaddition, watch of forblackish and flag

Leucostomapimples (pycnidia) infection. just beneath reddish bark that exude masses of spores is confirming evidence of Management - cal control options available for Leucostoma canker; materials used: There previously currently are are no nolonger effective on the chemi - proaches for control. Remove and burn or bury cankeredmarket. This twigs, leaves limbs, only or culturaltrees as managementsoon as possible. ap - ness of trees in autumn; avoid applying excess Minimizenitrogen fertilizer, winter injury late applications, by promoting and early late hardi sum-

unnecessarymer pruning. injury Minimize to trees; risk avoidof sunscald cultivating by using close toreflective tree trunks white and paint control on bark all borer of young insects. trees. And, Avoid

Fig. 4.5 (top). Typical Leucostoma canker infection on peach. Referenfinally,c esavoid: pruning during wet weather periods. Note the characteristic gum exudation and the flush cut Biggs, A. R. 1989. Integrated approach to controlling pruning wound entry point. Leucostoma 73:869-874. Fig. 4.6 (middle). Leucostoma canker growth on sweet cherry. canker of peach in Ontario. Plant Dis. Note the zonate growth pattern in the bark tissue (arrow). severity and non-chemical management of Cytospora Pokharel,canker inR. stoneR. and fruits. H. J. Larsen. Colorado 2009. State Incidence, University - Fig. 4.7 (bottom). Italian plum bark with Leucostoma pycnidia Western Colorado Research Center Annual report, (bumps beneath bark, arrow A) with oozing spore mounds (arrow, B).

2008. TR 09-12:55-62.

28 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology

Fire Blight Disease Cycle - biology: Fire blight is a bacterial disease of plants - : The bacteria overwinter within infect in the rose family. In fruit crops, it is economically ents and moisture at bud break enable them to ac- ed canker margin tissues. The spring flush of nutri - tively grow and colonize more tissues along canker Erwinia amylovora, is margins, eventually girdling and killing the branch spreaddestructive by insects, on apple, contaminated pear, and quince. pruning The or bactegraft- beyond the canker infection. Optimum tempera- ingrium tools, that wind,causes and fire rain-splash. blight, Flowers and fruit, Disease leaves and shoots, branches and whole trees are at Biology tures for disease development are 70-81°F (little risk of being killed once infected if weather condi- growth below 65°F or above 90-95°F) coupled with tions are favorable. Infections can destroy the cur- relative humidity of 80% or higher (little growth occurs at humidity below 65%). As colonies grow, reduce subsequent production, and even kill sus- millions of bacteria are forced from the surface of rent season’s crop, damage the tree structure and droplets of ooze consisting of liquid filled with devastating impact on orchard yield and long-term infected bark. Newly opened flowers serve as the survival.ceptible trees within a single season. This can have are attracted to the ooze and move the bacteria to initial spring infection site. Insects (bees, flies, etc.) Fire blight infections are categorized according to can happen by rain or irrigation droplet splash or opening flowers or other infection sites; this also the initial infection site: blossom blight, leaf/shoot blight, and fruit blight. Infection type incidence run-off. The bacteria then multiply on the flower changes with tree and crop growth through the stigma and are washed down into the floral cup by season. In spring, bacteria are carried to blossoms the blossom tissue through nectar secreting pores. rain or heavy dew. Once in the floral cup, they enter by insects and, occasionally, by wind and rain. In Infected blossoms quickly blacken and die within a early-and mid-summer, leaf/shoot blight frequent- few days. Infection then proceeds down the vascu- lar tissue so long as favorable weather conditions

succulently starts in young feeding growth wounds and of whose sucking populations insects (e.g., (warm temperatures, high humidity) continue. havepear psyllanot been and adequately green apple controlled. aphid) that Hail feed damage on the Shoot infections usually occur after blossom in- to these shoots can also provide entry for the bac- teria. In late-summer, fruit blight generally begins only on succulent new leaves and shoots as the fections have been initiated. These usually are when sucking insects such as stinkbugs or lygus bugs feed on the developing fruit after their usual bacteria enter through stomates (small pores for weed food sources dry up or are cut. Each of these damage, or wind can also serve as infection sites on gas exchange). Wounds from sucking insects, hail kinds of blight can move down the tree to progres- these tender tissues. Infection proceeds to older sively larger woody structures if weather condi- tissues in the branches and trees as in the case of tions remain favorable for disease development and - the initial infection is not removed. Even if weather tion until new growth stops. flower infections. The tree is susceptible to infec conditions change to allow the tree to stop the disease progression, drastic pruning and/or plant Fruit infections occur from blossom or shoot infec- surgery are called for. occur on fruit approaching maturity which have tions during early to mid-season. They also can varieties in pear, apple, and crabapple. For ex- Susceptibility to fire blight varies greatly between periods.had feeding Such damage infected by fruitsucking often insects has droplets (e.g., lygus of bug, stink bugs, etc.) during warm, moist weather ample, Bartlett and Bosc pears and Jonathan, Lodi, ooze on the surface which attract insects (as in the attentionRome Beauty, to avoid and possibleTransparent damage apples due are to allthe highly dis- susceptible to fire blight and require particular Cankerspring) activityand facilitate winds further down with spread cessation of the bacteria. of tree to be greater and more regular in areas with sig- growth in late summer and fall. Cankers on incom- ease. Occurrence and severity of fire blight appears pletely girdled branches tend to be the overwinter- ing sites for the bacteria. range.nificant Finally, summer the thunderstorm causal bacterium activity can such develop as the resistanceWasatch Front to agricultural in Utah and antibiotics along Colorado’s and complicate front Symptoms control programs; this has happened in certain ar- shoots with a scorched appearance are a character- : Leaves, blossoms, and young terminal eas of Utah. - soms and shoots initially become watersoaked and istic ultimate symptom of fire blight. Infected blos

Utah-Colorado Tree Fruit Production Guide 29 Chapter 4: Disease Biology

if mean daily temperatures are above 65°F com-

and,bined especially, with rain foror relativepresence humidity of ooze onabove any 65%). black- Scout orchards for infection symptoms (see above) should be patrolled during the bloom period to locateened shoots/flower any oozing cankers. clusters/fruit. If blight Pearresistance orchards to streptomycin is suspected, contact county Exten- Biology Disease Disease sion agents or the USU IPM Program (utahpests. - tanceusu.edu/ipm) in verifying (in Utah)the resistance or CSU Western and further Colorado infor - mationResearch on Center recommendations. personnel (in Colorado) for assis

Management: An effective management and control Fig. 4.8. Fire blight infection on Bartlett pear branch. Note the blackened, wilted shoot with “shepherd’s crook” above the damaged blossom cluster. and chemical aspects. program for fire blight should include both cultural Cultural Management: - Avoid stimulating excessive shoot growth. Ap- a dark green in appearance. They often also exude ply only enough nitrogen to produce 12-18 bacterial ooze (a difference from Pseudomonas bac- • inches of terminal growth annually. terial blast, caused by the bacterium Pseudomonas andsyringae, infected which tissue also and can tissues cause similarapical to flower the infec infec- Control sucking insect populations, weeds, and tionstions). turn Infected black blossoms,in pear and leaves, brown and in appleshoots and wilt, succulent plant growth on which they can build eventually dry up and hang on to the tree through • up. most of the dormant season. Infected terminals -

reddish(shoot ends) brown often tend develop to run downa curled, the drooping cambium end, layer • asReduce pyracantha, fire blight hawthorn, inoculum cotoneaster, near or in andthe orwild beneathcalled a “shepherd’s the bark in activecrook” shoot (Fig. or4.8). branch Streaks infec of- crabapplechard by removing growing nearany hosts the orchard. of fire blight such tions. Small droplets of amber ooze are a diagnos- -

Fruittic sign infections of fire blight on both infection. apple and pear begin with • Select fire blight resistant cultivars: apple culti vars with good resistance to fire blight include fruit. Droplets of ooze commonly are present on cultivarsred Delicious, include Liberty, Duchess, Prima, Golden Priscilla, Delicious, Redfree, thea firm fruit brown surface. rot thatInfected quickly fruit includes gradually the shrivel whole Spartan, and Sir Prize. Moderately resistant and can remain attached through the winter. blightGranny resistance Smith, Honeycrisp, include: Harrow Jonagold, Delight, McIntosh, Har- Cankers, slightly sunken areas of bark tissues, Mutsu, and Winesap. Pears with moderate fire- develop when the infection from more succulent glow, and Seckel. vest Queen, Kieffer, LaConte, Magness, Moon margins may crack as the canker dries out in late • Orchard sanitation: Remove all limbs with summertissues progress or fall. Cambiuminto woody streaking tissue. Theslows canker as the blight during the dormant pruning season or trees wall off the infection when conditions become when found. Cut 8-12 inches below any exter- nal evidence of blight and check for a reddish streaks extending upward or downward from the color in the cambial layer beneath the bark at cankerunfavorable are indications for infection that expansion. the canker The infection lack of has that point. If found, active bacteria have prob- become “dormant.” ably already reached that point, and another cut lower on the limb/branch will be required. Monitoring -

look for open: Monitor blooms, orchard abundant and succulentweather condi shoot growth,tions for or those fruit that with favor extensive blight hail development or insect injury (e.g., beExcept carried during to other dormant branches pruning, or trees tools through MUST BE- DISINFECTED AFTER EACH CUT or blight may

30 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology

out the orchard. Soak the tools in a dilute be labeled only for apple. Do not apply sprays containing copper to Anjou pears; russet may result. solution of household bleach (1 part bleach + 9 parts water) or alcohol (7 parts alcohol + 3 - References: lutionsparts water) should for be at made least fresh30 seconds daily and or spray changed tools and cuts with Lysol disinfectant spray. So Evans, K., et al. 2008. Fire Blight. Utah Pests Fact Sheet Disease no.blight-08.pdf PLP-009. Utah St. Univ. Extension, Logan, UT. 4 pp. Biology at least every 4 hrs. The alcohol solution and extension.usu.edu/files/publications/factsheet/fire- RemoveLysol spray cankers are less on corrosivethe larger to limbs pruning and trunkstools. Powdery Mildew that need to be saved by scraping. Be sure to biology - • remove all the discolored tissue. Carry-over ferent fungi that form a greyish-white powdery cankers should be treated during the dormant coating: Powderyon terminal mildew shoots is andcaused leaves. by several It also difmay period. Any oozing cankers found during bloom should be removed promptly, and the if the fruit are infected at relatively early stages of tools and cut surfaces disinfected. In summer, form a network of lines (russet) on the fruit skin scrape cankers in hot, dry weather to minimize strands and spores which are microscopic in size. possible reinfection. In all cases, remove the Becausedevelopment the spores . The powderyare extremely mat consists numerous of fungaland outer bark down to the cambial layer and out easily spread by wind, many infections can occur. to one inch beyond the canker margin. Remove - and burn all blighted prunings and canker resi- creasingly destructive. dues from the orchard. Thus the disease can become widespread and in Apple and cherry powdery mildews have been Chemical Control: most common and economically important in Colorado and Utah orchards. Apple powdery Cougarblight to determine when to spray. mildew, caused by Podosphaera leucotricha, also • WhenUse forecasting infection periodsmodels suchoccur, as apply Maryblyt suitable or causes occasional problems in pear, peach, and preventative bactericide sprays. Blossom nectarine. Cherry powdery mildew, caused by sprays are effective for 3-5 days because new Podosphaera clandestina P. oxycanthae blossoms open and need protection if condi- a close second in incidence and very important tions continue to favor disease development. to cherry growers; tart cherry (syn. fruit with infected) is In summer, apply sprays during the cooler - tive for 5-10 days and may need to be repeated stems tend to be more difficult to harvest by ifhours conditions of the day.favorable Protective to blight sprays development are effec nectarinesshaking because are damaged the fruit by doesn’t the peach release powdery from the continue. Foliage and fruit sprays may have to mildew,stems as Sphaerotheca readily as non-infected pannosa, as fruit. well Peachesas the and

within 1-2 hours after application or if heavy be repeated if moderate rain (.25-.5 inch) falls- problems;apple powdery the causal mildew powdery (causing mildew peach forrusty these spot plication. cropson both). grown Apricot along and the plumwest coast,here have P. tridactyla had fewer, has rain (0.75+ inch) falls within 8 hours after ap not been reported thus far from either state. All of Spray material alternatives include antibiot- these powdery mildews behave similarly with early control needed to avoid fruit damage in orchards • compounds, and biological control products where they occur. ics (streptomycin and oxytetracycline), copper be used in areas where streptomycin resis- Disease Cycle (e.g.,tance Bloomtime has been reported, FD). Oxytetracycline e.g. Utah County should in apple powdery mildew and for those powdery Utah. Streptomycin cannot be used within 30 : The disease cycle differs slightly for days of harvest on pears or within 50 days of harvest on apples. See previous comments overwintersmildews restricted as mycelium to stone in fruitthe buds crops. or Theas cleis main- differences are whether the specific mildew fungus is suspected. Bordeaux mixture or copper ma- under Monitoring if resistance to streptomycin crackstothecia and (small, crevices. spherical, black, sexual fruiting caution as some are phytotoxic to pear and may bodies) on detritus on the orchard floor or in bark terials such fixed copper should be used with

Utah-Colorado Tree Fruit Production Guide 31 Chapter 4: Disease Biology

leaf infections occurring at night when humidity is terminal and fruit buds, primarily as mycelium high and temperatures cooler. Rusty spot infections The apple mildew fungus overwinters in infected bud tissues. Cleistothecia serve only as a secondary peach and nectarine cultivars between shuck split overwintering(thread-like, multicellular mechanism. structures) As the buds within open thein the and(from pit apple hardening. mildew) Nonglandular, affect only fruit pubescent of susceptible peach spring, the mycelium grows out into the develop- varieties are the most susceptible to peach mildew ing shoot and leaf tissues and produces asexual infections. Cleistothecia have been found in the fall occasionally on infected rose shoots, but not on in- borne and germinate readily at mild temperatures fected peach or nectarine shoots. summer spores (conidia). These spores are wind- Biology Disease Disease are largely on leaf surfaces, penetrating the surface Symptoms: Infected leaves, shoots, and fruit are cov- cellsand high here humidity. and there Theto obtain resulting leaf newnutrients. infections Cloudy, ered by a light grey or white powdery coating of overcast conditions with 70 - 90°F temperatures favor disease development until shoot growth stops curled, crinkled, and stunted . Infected shoots spores and mycelium (Fig. 4.9). The leaves become

treesin late-June can severely to early-July, damage when them. temperatures Infections on reach thebecome young stunted fruit surface (much damageshorter distancethe fruit skinbetween cells olderinto the trees upper result 90’s. in smallExtensive & damaged infection fruit, on youngreduced small, crinkled white-coated leaves). Infections on

buds. Bud scales on infected buds fail to close com- (the fruit epidermis) and result in scarring of the yields,pletely, and causing winter-kill them to of be infected less protected flower and from leaf the Infruit cherry, surface small, known roundish, as russet light-colored (Fig. 4.10). spots ap- cold. pear on leaf surfaces within the interior tree cano-

Cherry powdery mildew overwinters as cleisto- remain separate or coalesce to give the infected leaf py shortly after bloom. These mildew colonies may infections may become puckered or even blistered. 1thecia hr exposure on orchard to moisture floor detritus in spring and andin bark usually cracks a whitish, mealy surface color. Leaves with severe and crevices. The cleistothecia rehydrate with depressed, roundish areas on the fruit surface with bloom time. Optimum temperature for spore re- aMildew very sparse colonies cobwebby on ripening growth fruit on appear the surface. as slightly Se- leaserelease following their ascospores cleistothecia (sexual re-wetting spores) is around 59°F vere fruit infections may cover the entire fruit with and optimum temperature for spore germination is 68°F. Initial infections occur on trunk sprouts without illumination of the fruit from the side. close to main scaffold branches or on leaves just a scant mycelial growth that is very difficult to see above tree crotches. Spores from these then spread In peach, peach mildew infections produce a thick, secondary infections to shoots throughout the tree; felty mycelial growth on both shoots/leaves and many or most terminal shoots may become infected throughout and following fruit harvest. Green fruit brushed off of the fruit, a pronounced russet of the are most susceptible to infection; fruit infections fruit (Fig. 4.11); when this mycelial growth is in mid-summer. Affected leaf and shoot growth is cherry fruit with infected stems tend to be more stuntedfruit surface and irregularlyis observed. curled; The disease affected first leaves appears be- become apparent if rain occurs near harvest. Tart with the apple powdery mildew develop thin, rusty- non-infecteddifficult to harvest fruit. by Cleistothecia shaking because are produced the fruit on orange,come crisp cobwebby and dry patches with time. on the Peach fruit fruit surface infected fuzz. shootsitself doesn’t and leaves release in fall.from the stems as readily as scarring of the fruit skin beneath. Sphaerotheca pannosa, overwinters These patches eventually slick off to reveal a netted as mycelium inside dormant infected rose buds and Monitoring onPeach inner mildew, bud scales of peach in milder climates. - lial coating: andApple terminal growers buds should that watchare not for tightly flagged terminals (shoot terminals with a whitish myce arePrimary carried infections by wind on to emergingnewly emerging shoots leaves(mostly and pruning. As buds emerge in spring, look for and re- producerose shoots) secondary produce infections conidia (asexualon rose andspores) peach. that closed). These should be removed during dormant Secondary infections of foliage takes place through- dwarfed shoot growth covered with white myceli- out the growing season. Optimum germination move flagged shoots or spurs (shoots or spurs with and pear growers should watch for any shoots/ um and powdery spores). At and after bloom, apple temperature is 70°F (range 36-99°F) with most 32 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology

leaves/developing fruit that develop a whitish my- celial growth or powdery spore covering. Control sprays should be applied from prebloom/early bloom to cessation of terminal shoot growth if in- fections are found on susceptible trees.

Cherry growers likewise should monitor leaves on Disease suckers and spurs arising from lower parts of main Biology scaffold limbs just above limb crotches for small, roundish mildew spots beginning with early bloom.

susceptibleBlack Tartarian, to cherry Bing, mildewRanier, and Lapinsneed close sweet moni - toring.cherry andInfected Montmorency water sprouts tart cherry should are be removedhighly between bud break and full leaf development. A control spray program should be started as soon as infection spots are observed and need to be contin- ued until fruit begins to ripen.

for development of white, thick, felt-like mycelial patchesPeach growers or less needobvious, to monitor roundish, shoots rusty-orange and fruit patches of mycelium on peach and nectarine fruit surfaces from bloom through pit hardening. A con- trol spray program likely will be needed if several colonies per tree are found.

Management - mized through cultural management and chemical : Powdery mildew impacts can be mini type and mildew type involved. control options. These will differ with the crop Cultural Management: Overwintering inoculum of apple powdery mildew can be reduced with attention to or- •

chard sanitation. Judicious removal of flagged isterminals a second. during dormant pruning is the first step; scouting for and removing flagged spurs Selection of apple and pear cultivars resistant Fig. 4.9 (top). Apple powdery mildew infection on peach shoot. Note powdery clusters of spores and infolding and • Rome, Gala, Granny Smith, Fuji, Honeycrisp, twisting of infected leaves. to apple mildew is another tool; Jonathan, to apple mildew while Golden Delicious and Fig. 4.10 (middle). Jonathan apple fruit russetted by early and MacIntosh apples are all very susceptible season infection with apple powdery mildew. Left most fruit is non-infected. andJonaGold red Delicious are moderately are resistant susceptible. cultivars. Freedom, Anjou Fig. 4.11 (bottom). Peach fruit infected with peach powdery pearLiberty, is susceptible Prima, Goldrush, while BartlettJonafree, pear MacFree is mod - mildew (left) and apple powdery mildew (center & right). Note the rusty orange mycelial patch on the peach fuzz in the center in Anjou and even Bartlett pear are greatest fruit and the russetted fruit skin in the right fruit. whenerately planted resistant adjacent to apple or mildew. near a block Problems of highly susceptible apple cultivars in which control is lax. In addition, proper pruning to allow good

Utah-Colorado Tree Fruit Production Guide 33 Chapter 4: Disease Biology

light penetration and air movement through - the canopy will reduce humidity within the tree canopy and minimize incidence of infection • provideQuinone good outside control, Inhibitors but have (QoI risk fungicides of develop ) in- conditions within the trees. clude strobilurins such as Flint & Sovran, These

Similar pruning of cherry and peach is an im- ing resistance and cross-resistance with DMI portant cultural management component for fungicides (previous category). - • cherry and peach powdery mildews. Keep wa- ter sprout growth from scaffolds to a minimum • Succinate dehydrogenase inhibitors (SDHI fun gicides) include carboximides like boscalid. - Biology Disease Disease

(reduce availability of susceptible tissues early • Combination products include Pristine (strobi Chemicalin the Control:growing season). Biocontrollurin + carboximide products: mix), include which bacterial works antago well. - nists such as Serenade and Sonata. • • fungicides,Spring and andsummer the combination sprays of sulfur of a (whenstrobilurin andtemperatures carboximide are fungicide below 80°F), can providecertain DMI effec - tive control of apple, cherry, and peach mildew. • Oils: include plant oil products (Sporan, Erase) Avoid developing resistance to effective control and highly purified paraffinic oil products chemistries by rotating modes of action for (Stylet-Oil). Oils can be combined with other sprays applied throughout the season Available morecategory time materials for absorption (except of sulfurs limited or systemic captan) modes of action groups are as follows: to enhance efficacy (slows drying and allows Oil applied on 14 day intervals at a 1% vol/vol ratematerials provided like excellentDMI’s and control strobilurins). of apple Stylet- mildew

• Multi-site contact activity materials include potassium bicarbonate products (Kaligreen), - in Colorado-based trials during the 1990’s. - sulfur products (flowables, wettable powders, vide limited control at best. micronizedlime to make powders, lime-sulfur dusts), sprays and for calcium dormant poly • Potassium salts of fatty acids: e.g., M-Pede, pro treatments.sulfide products Sulfur (e.g., products Sulforix) are combined phytotoxic with References: when applied with or within 10 days of any spray containing oil except in dormant sprays. Thomson, S.V. and Ockey, S.C. 2000. Apple Powdery - Mildew.tions/factsheet/apple-pm00.pdf. Utah Plant Disease Control No. 16. USU Coop. overwintering cleistothecia with which they Ext., Logan. 3 pp. extension.usu.edu/files/publica Dormant sprays with Lime-Sulfur can kill

Thomson, S.V. and Ockey, S.C.utahpests.usu.edu/plantdis 1999. Powdery Mildew of- daytimecome in contact.temperatures Sulfur reach sprays 80°F (especially or higher with eases/htm/fruit/powderymildewStone Fruits. Utah Plant Disease Control No. 51. USU canwettable cause powder phytotoxicity formulations) to apple, applied pear, and when nec - Coop. Ext., Logan. 3 pp. tarine fruit and foliage. Cherry and peach are Phytophthora Crown and Root Rot less susceptible to damage, and micronized and biology: Phytophthora crown and collar rot of fruit trees is a fungal disease that affects all species of daytime temperatures as high 90°F if applica- tionsflowable made sulfur early formulations in the morning can whenbe used fruit under trees 5-7 years in age, about the time they begin to temperatures are at their coolest. Cooled fruit bearpome fruit. and stone fruit. The disease frequently kills have less risk of phytotoxicity to sulfur later when daytime temperatures are above 80°F. - nus Phytophthora; P. cactorum attacks apple and pearThe disease while several is caused closely by species related of species the fungus attack ge P. cambivora, P. mega- • Demethylase Inhibitor (DMI) products include sperma, P. dreschsleri, and P. syringae. All are more myclobutanil (Nova/Rally), triadimephon - activestone fruits.in wet Thesesoils and include at soil temperatures of 55- vide(Bayleton), good control, fenarimol but (Rubigan),have risk of tebuconizole developing 70°F. All are water molds that produce swimming resistance(Elite), triflumizole and cross-resistance (Procure), etc. with They QoI profungi- spores which facilitate spread through wet soils and irrigation water and which attack the tree roots

cides (next category).

34 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology

in heavy, poorly drained soils than in light, well- drainedand crown soils. tissues. But it The can diseaseoccur in is any more improperly serious irrigated soil.

Disease Cycle incompletely known. It is known that the fungus : The disease cycle for this disease is Disease can be introduced into an orchard through infected Biology planting stock, contaminated farm implements, or through contaminated irrigation water. Swimming spores are released and attack tree roots and crown tissues. Initial infections result in cankers on the trunk between the soil line and the crown roots.

releaseThe fungal more mycelium swimming growing spores out under of the favorable infected soil tree tissues into the soil produce sporangia (which are more resistant to unfavorable soil conditions Fig. 4.12. Crown rot canker on apple. Note the narrowly conditions) and sexual structures (oospores) which rounded and sharply sunken upper edge of the canker. germinate under favorable soil conditions and produce(dry soil sporangiaand unfavorable and swimming temperatures). spores Oosporesto enable Monitoring: Check orchards in mid-summer for new infections. trees with weak aerial growth, especially in orchard areas prone to poor soil drainage or low spots that Symptoms - may experience ponding. In late summer to early fall, check for trees in these areas that may exhibit on the bark: The between most evident the soil symptoms line and crownare dead roots. ar premature development of fall leaf coloration, espe- eas (cankers) on the base of the tree. These begin- cially development of reddish or red-purple colors. creasingly sunken and the canker expands slowly; Check these trees for reddening bark coloration. theThe upper infected canker bark margintissue darkens often is andnarrowly becomes rounded in

above the soil line, but detection often requires re- Then check the trunk at and below the soil line (Fig. 4.12). Cankers may extend up to 18 inches samples at the edge of the canker can be collected for any canker development or presence. Tissue cankers gradually girdle the tree completely and moval of soil from around the trunk of the tree. The presence of Phytophthora. for an attempt to isolate the fungus and confirm the and easily moved from side to side, just as are new Management: Best control is obtained through pre- treeskill it. that Trees have with experienced collar rot arewind-rocking. poorly anchored ventative cultural management practices. Eradicat- Aerial symptoms on infected trees are similar to - Culturaling infection Management: is difficult. clude development of scattered yellow leaves on Select orchard sites with light soils and good treesthose inproduced mid-summer. by other In latetree summerdisorders. to fall,They the in drainage. Keep water away from tree trunks foliage of affected trees often develop a reddish • -

is directly related to the degree of girdling at the (no basins around the trunk, space trickle irri or purple cast (intensity of the red-purple color on raised beds; keep irrigation runs to 8 hrs or less.gation outlets away from the trunk); plant trees annually in infected trees, and bark color becomes tree crown). Vigor and leaf production decrease Select varieties and rootstocks resistant to col- lar/crown rot; do not plant susceptible root- foliar and branch bark symptoms may appear • stocks where soil is poorly drained or heavy. onlyincreasingly on branches red to directly reddish above orange the over trunk time. canker. These - mouse or rodent trunk girdling injury, and winter For apple: East Malling (M) rootstocks M-9, Crown borer and flat headed borer trunk damage, injury to the tree trunk can produce similar foliar M-26, M-7, and M-111 have reasonable to inter symptoms. Because of this, the only positive diag- susceptible;mediate resistance seedling while rootstocks Malling-Merton vary, but ap(MM)- nosis is the appearance of the cankers and isolation rootstockspear to be somewhatMM-104 and tolerant MM-106 of collar are quite rot. For of the fungus.

Utah-Colorado Tree Fruit Production Guide 35 Chapter 4: Disease Biology

References: whether as a sweet or tart cherry rootstock, cherry: Mahaleb rootstock is quite susceptible Thomson, S.V. and Ockey, S.C. 2000. Phyophthora Crown less susceptible. For peach, nectarine, apricot, and Collar Rot of Fruit Trees. Utah Plant Disease while Mazzard, Stockton Morello, and Colt are Controlphytophthora-fruit-trees00.pdf No. 6. Utah St. Univ. Coop. Ext., Logan. 3 pp. extension.usu.edu/files/publications/publication/ and plum trees on Nemaguard, Myrobalan Replant Problems plum.plum, or Marianna 2624 have better survival biology: Orchard trees replanted into soil previously than trees on apricot, Lovell peach, or domestic Biology Disease Disease from a reputable nursery with a good history of poorlycropped than to the the same same tree trees type planted (apple into after virgin apple, soils • qualityPurchase trees. and plantDo not only plant disease-free trees with treesdamaged orpeach soils after previously peach, etc.)planted often to growa different slower type and of more or discolored roots. crop. As a result, the onset and rate of fruit produc- tion is slowed for those trees. In addition, total Avoid deep planting; plant trees with the graft fruit production and crop returns over the life of union several inches above the soil line. Scion • varieties often are more susceptible to collar proposed reasons for this: rot infection than are the rootstocks, and trees the orchard planting are reduced. There are several planted with graft unions at or below the soil 1. Depletion of necessary soil nutrients by the line have increased potential for the scion to preceding crop. self-root and provide an entry for collar rot. 2. - ous crop root system or by breakdown of the Support newly planted trees. Wind will “rock” previousProduction crop of phytotoxicroots after residuestree removal. by the previ newly planted trees if not supported and create • a “well” around the tree base which will collect 3. Build-up of soil populations of fungi, bacteria, water and increase cold injury and collar rot. and nematodes adapted to feeding on the roots of that particular type of fruit tree. Other Control options:

crops for which these are registered can help because treatment of these soils with soil pesti- The third explanation seems to be the most likely • avoidPreventative collar / treatment crown rot withproblems. fungicides on cides (nematicides, fungicides, broad-spectrum soil Several approaches can help provide control - fumigants) has enhanced growth of new trees in after infection. One can bridge-graft over dam- - old orchard soil. Narrow-spectrum treatments (ne • aged tissue if less than 30-50% of the trunk ment of new growth than treatment with broad- maticides, fungicides) often provide less enhance circumference is affected, inarch graft 1-yr-old whips of a resistant variety into the trunk well spectrum soil fumigants (e.g., methyl bromide, above the diseased area. Remove soil from trees in soils treated with soil fumigants typically chloropicrin). In addition, growth rates of the new around the base of infected trees and allow diminish over the initial 3 years after planting to the infected area to dry out and stop further become equivalent to those of trees in non-treated progression of the disease. Spray the lower - problem is a complex interaction of the soil nema- todes,soils. Thus,fungi, it bacteria, is likely andthat microfauna the cause of that the slowreplant trunk with a fixed copper fungicide (50% me root growth and function. trunktallic copper), with fresh using soil 2-3 in late Tbsp autumn of fungicide/gal. in order to preventof water. winter Refill theinjury soil to depression the tree collar. around Irriga the- Disease Cycle tion practices that keep the soil saturated for of orchard replant problems other than that they : Little is known about the disease cycle 36 or more hours should be avoided, especially develop over time and take about 3 years to be re- when temperatures are 60-70°F. Finally, soil established in soils treated with broad spectrum fumigants or in virgin soils used to replace old or- chard soils within an orchard block being replant- helpful.drenches Check of metalaxyl on new (Ridomilregistrations Gold and EC) ratesor fora foliar these sprays systemic of phosetyl-Al fungicides. (Aliette) can be requires about 8-10 years to return the soil to a stateed. Rotation comparable to another to virgin type soil of for crop the (e.g., initial alfalfa) crop.

36 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology

Symptoms: Symptoms are slower growth of trees re- planted into soils planted to the same type of tree previously. In addition, onset and rate of increase becomingmethyl bromide increasingly or methyl regulated iodide because(broad-spectrum of the risk of fruit production to full cropping capacity is tosoil the fumigants). applicator, Application passers-by, ofand soil the fumigants environment. is slowed. Affected trees take 8 yrs or more to reach full cropping production. depth and the soil left undisturbed for at least a They need to be injected into the soil at 18 inches Disease Monitoring: No monitoring is done since the prob- Biology lem cannot be corrected once the replant trees are week. They also have minimum soil temperature planted. Referenthresholdsces: for application (often 50°F or above). - Management: Several approaches have been used to Larsen, H. J. 1990. Countering Orchard Replant Prob address orchard replant problems. First is crop ro- Nematodelems. Proc. W.Problems Colo. Hort. Soc. 47:46-56. biology: Nematodes are worm-shaped nearly mi- tation: This usually requires a rotation of 8-10 yrs to a crop different than the original crop (e.g., peach the naked eye when they are in the soil or within plantcroscopic material. animals. Of the They known are virtually nematode invisible species, to Anotherto apple, ispeach to replace to alfalfa, old orchardetc.). soil with virgin approximately 50% are free-living species found soil or soil from a different crop. Dig a 3 ft x 3 ft x 3 ft deep hole and replace the soil in the hole with in soil or freshwater, 25% are marine (found in sea- single tree or a few trees within an existing old or- water),ing nematodes 15% are are animal very importantparasites, andin maintaining 10% are chardfresh soil. block. This labor intensive option is best for a knownthe soil plantbio-dynamic parasitic system, nematodes especially (PPNs). in soil Free with liv A third option is soil solarization: Homogenize the - low organic matter content, whereas PPNs feed on cient soil moisture to encourage seed germination, Freeplants living and reducenematodes crop indirectly growth and disseminate yield efficiency. andsoil tocover very the small, prepared uniform ground soil units, with oneprovide or two suffi lay- - ers of transparent plastic mulch. Seal the edges of vances microbial colonization of substrates and promotesmicrobial propagulesnutrient mineralization. throughout soil. In addition, This ad will heat the soil beneath the clear plastic over time the mulch by burying them with soil. The sunlight bacterial growth by releasing growth-limiting threshold for control of soilborne pathogens is nematode metabolites may also stimulate specific 99°F,to temperatures and control as is highincreased as 140°F. the longer The temperature tempera- bacteria and fungi within the soil and are, in turn, - nutrients (such as N and vitamins). Many feed on tic remains on the soil plots in the summer months, tures remain above this point. The longer the plas improvespreyed upon nutrient by generalist cycling andpredators allows (includingslow release - the omnivorous and predatory nematodes). This pleted,the deeper the plasticthe heat mulch will penetrate can be removed (it needs and to trees treat as far down as 3 ft.). Once solarization is com planted into the treated soil, taking care not to pull of nutrients. The contribution made by free living untreated soil into the planting hole. isnematodes relatively tohigh N mineralization compared to bacteria (making in N soil available eco- to plants) and mineralization of other soil nutrients A fourth option is soil pasteurization through use - of low pressure steam to raise soil temperature to systems. These free living nematodes also feed on - other soil microbes including plant pathogens (bac sure steam generation is rarely available to grow- teria, fungi and nematodes). Another group, called 160°F for 3-4 hrs. However, field-friendly low-pres Steinernema and Heterorhabditis lethalentomopathogenic to many important nematodes soil insect (e.g., peststhe genera and yet is ), is extraordinarily ers. The process does allow replanting within a safe for plants and animals; they are used to control day or two after treatment (when soil temperatures many soil inhibiting insects. return to 70°F or below). Nematode females lay eggs singly or in masses in involves use of restricted use pesticides such as The last option is soil fumigation. This typically usually go through four molts before reaching ma- - the roots or surrounding soil. The wormlike larvae Telone II (a nematicide), Telone C-17 (combination turity. Nematode survival, growth, and reproduc- nematicide + broad-spectrum fumigant, chloropic rin), chloropicrin (broad-spectrum soil fumigant), Utah-Colorado Tree Fruit Production Guide 37 Chapter 4: Disease Biology

tion depend largely on soil moisture, temperature toma canker infection, cold injury, or other stress in soil and/or host tissues, and availability of a food factors under Colorado conditions. - able conditions, nematode reproduction will con- Plant Parasitic Nematodes Important in Fruit tinuesource until or suitable the food host supply plant is (PPNs).exhausted. Under However, favor Crops of Colorado and Utah: nematodes can survive in poor soil conditions as Eight plant parasitic nematode genera have been found in fruit orchard soils in Colorado during species feed on aerial plant parts, but the major- - eggsity of or nematodes larvae. Among feed on the underground PPNs, a few plantnematode parts ger, spiral, root-knot, lance, citrus, ring, and stunt recent soil surveys. These are the root-lesion, dag Biology Disease Disease using a spear-like structure called stylet, which is root-lesion and the dagger nematodes. (roots, bulbs, and tubers). They feed on plant cells nematodes. The most important of these are the hollow structures to withdraw plant cell juice by Root-Lesion Nematode (Pratylenchus spp.) distinct in most PPNs. They use these small, sharp, Root-lesion nematode can be a major cause of or-

sucking and thereby weaken the host plant. These root and burrow tunnels through the root cortex. PPNs may be endoparasitic (remaining and feeding Allchard life replant stages, failures.except the Lesion egg stage, nematodes are motile enter and the inside the cell), semi-endo or semi-ecto parasitic - can invade roots. Eggs are laid inside root tissues or (half body inside and half outside plant surface), and ectoparasitic (remaining and feeding from out the roots and contribute to root injury. Root lesion Whenside the large plant nematode cell). populations feed on a plant nematodesin the soil. Theyare migratory hatch, and and the therefore juveniles are then capable enter of repeatedly entering and exiting from root tissue, take up water and minerals and to transport nutri- although several generations can occur inside the root system, they interfere with the roots’ ability to- roots without the nematodes migrating into the es plant vitality, and inhibits/retards shoot growth, theents combination to the shoot. of This which restricts decrease root crop growth, quality reduc brown lesions on the white lateral roots and kill the and/or yield. In addition to the direct injury to the surrounding soil. These nematodes cause small plant resulting from feeding activities, nematodes discolored when these lesions merge. Such root le- are thought to inject injurious substances into the sionsfine feeder are frequently roots. The invaded entire rootby other system root-rotting appears plant when they feed. Nematode injury to plant pathogens. Severely affected trees may lose all roots also may increase damage to these plants by feeder roots. Ultimately, young replant trees may disease-causing fungi and bacteria. Certain nema- die and existing trees lack uniformity. If not dead, tode species also are known to transmit other plant the top part of the infected tree often exhibit stunt- pathogens, especially plant-pathogenic viruses. a decline in vigor of existing peach and cherry or- In addition, feeding injury by these nematodes chards.ing, chlorosis, and twig dieback. They can cause

A large number of lesion nematodes in a root fre- predispose fruit trees to cold injury (winter injury cankerand/or infection;spring frost), all of high these soil are pH common susceptibility, problems presence of brown lesions composed of dead root inmicro western nutritional Colorado deficiency, fruit orchards. and to Leucostoma Conversely, tissuesquently is cause a common the root symptom to turn brownof lesion and nematode die. The infection; however, roots of some plants are not soil health status, and other disease infections also sensitive and do not turn brown. In addition to the maypoor predispose tree nutrition, plants orchard to cold floor injury management, and nematode death of root cells caused directly by the nematode movement and feeding, wounds resulting from fruit crops, e.g., Pratylenchus spp., Xiphinema spp, nematode activity allow other soil microorganisms Meloidogynedamage. The spp. common Helicotylenchus PPN species sp., associated Criconemoides with to enter the root tissues and contribute to root sp., and Tylenchulus sp, also are common in many fruits that causes damage in apple, peach, cherry, or in combination with other factors reduce the grapesdecay. Theand mostso many common other root-lesioncrops is P. vulnus nematode. in Colorado fruit orchards. These nematodes alone X. americanum Dagger Nematode (Xiphinema spp.) and/productivity or the nematodes of the trees. weaken Some PPN the treesspecies to the(e.g., ) transmit plant viruses. These viruses- This is the largest of the plant parasitic nematodes point that they are more easily killed by Leucos found in our orchard soils. Up to 2-3 mm (2,000 -

38 Utah-Colorado Tree Fruit Production Guide Chapter 4: Disease Biology Disease Biology

Fig. 4.13. Dagger nematode adult. Inset photo shows its stylet Fig. 4.14. Sweet cherry leaves with roughened tissue out- with characteristic flanges on stylet basal bulb. Bar=100 um growths on their undersurface, characteristic symptoms of (applies only to the whole nematode). infection with cherry rasp leaf virus.

nematode populations observed in western Colora-

direct3,000 um)damage in length, to a wide it has variety a characteristic of plants by flanged their feedingbulb at theactivities, base of but its styletseveral (Fig. dagger 4.13). species It causes also mldo cherrysoil is enough orchards to (15-70transmit nematodes/100 cherry rasp leaf ml virus. soil in sweet cherry) are very high as 1 nematode/100 observed in all most all fruit orchards in Colorado in progress. Some other important fruit viruses irrespectivetransmit soilborne of crop, plant location, viruses. soil type,This nematodeetc. Females is transmittedThe identification by dagger of species nematode found are in grapevineColorado isfan lay eggs singly in the soil near plants and these leaf virus, grapevine yellow vein virus, tobacco ring spot virus, peach rosette mosaic virus, and three 3-4 juvenile stages and may require 6-12 months hatch to produce first stage juveniles. They have - this nematode may live up to 3 years under favor- strainsruses are of acquiredTmRSV causing within peach24 hours yellow of the bud initiation mosaic, ableto complete soil conditions. their life Daggercycle. Males nematode are rare densities and pruneof feeding brown and line, are andcarried Prunus in the stem esophagus pitting. lumenThe vi observed in most western Colorado apple orchards - ted by both adults and juveniles. - for up to 12 months. Virus particles are transmit (18-152 nematodes/100 ml soil) are above the Symptoms: Symptoms caused by most of the plant levelseconomic are notthreshold known level for other for apple fruit (10-100 crops. Ectopar nema - asitictodes/100 dagger ml nematodes soil). However, do not economic burrow intothreshold roots, from those caused by other soil related problems. but insert their long stylet deep into root tips where parasitic nematodes are difficult to distinguish they feed on root tip cells. Dagger nematode feed- Symptoms include: non-uniform plant growth, ing causes some necrosis and stunting and swelling mostlyThus, identification in patches and based with on poor symptoms plant establish is not easy.- of root tips. Several lateral roots may appear above ment –giving an unhealthy appearance; chlorosis the damaged root tips. Root-tip swelling may be confused with the galls of root-knot nematodes. - and stunting (resembling symptoms of some virus Species of dagger nematode transmit many im- infections); stubby roots, bifurcated roots, root le portant fruit viruses; 11 species of Xiphinema are poorsions, root root health, galls (knots); growth, excessive and establishment. root branching and proliferation (“hairy root” symptoms); and Monitoring: Nematode populations and species commonknown to problem transmit in 13 western NEPO viruses, Colorado including cherry within soils of production blocks are monitored by Cherry Rasp Leaf Virus (CRLV), an important andX. collecting soil samples in a representative pattern rivesi and X. americanum is tomato ringspot virus orchard (Fig. 4.14). Another virus vectored by According to unpublished information, X. thorneii (usually as a transect or a zig-zag pattern) across and(TmRSV), X. utahensis which arecauses present prunus in Colorado. stem pitting Only (PSP). X. eachthe production sample and block. placed Approximately into a plastic bag1 cup for (~250 trans - americanum portml) of to soil the is extraction collected location.from the topA 100 foot ml of subsample soil for

is reported as a vector of CRLV. Dagger

Utah-Colorado Tree Fruit Production Guide 39 Chapter 4: Disease Biology

is taken from each sample and the nematodes con- ensure adequate moisture, cover with plastic, seal tained are extracted by density centrifugation, elu- the plastic to make it air tight and maintain the seal triation, or wet sieving for enumeration and iden- - tion combined with green manure crops should be are compared to the economic damage threshold morefor at effective.least 45 days in June and July. Soil solariza tification. Once identified and counted, the results Organic growers can use Ditera ES at 5-40 Gal/A, Ditera DF at 13 - 100 lb/A, or Ditera WDG at 13 - for that species, crop, and soil type (Table 4.1). 100 lb/A. Apply to soil before planting or to foliage Table 4.1. Peach economic damage thresholds (number/ 100 ml soil) in clay to clay-loam soil of eight nematode genera of growing plants. Biology Disease Disease found in orchard soils of Colorado. Conventional growers can consider preplant soil Threshold Nematode (genus) (no./100ml soil) Root Lesion (Pratylenchus) 500-1000 fumigation. Use Telone C-17 at 11 - 17 gal/A, Dagger (Xiphinema) 50-100 222Telone - 350 II at lb/A. 9 - 15 Apply Gal/A, soil Vapam fumigants (Metam when sodium) the Lance (Hoplolaimus) 40-150 soilat 40 temperature - 100 gal/A, is or 50-80°F Basamid at 99G 6” soil (dazomet) depth with at Ring (Criconemoides) 250-600 critical to get affective results. Covering soil after Root Knot (Meloidogyne) 100 appropriate field moisture. These conditions are Stunt (Tylenchorhynchus) 150-300 Citrus (Tylenchulus) 10-100 application of the soil fumigant increases efficacy of Spiral (Helicotylenchus) 300-500 the treatments. (Restricted use: pesticides certified Hostapplicator resistance only).

Management - : Many rootstocks are reported atodes must focus on reducing nematode numbers to have tolerance or resistance to PPNs: In grape, to levels below: Most the of damage the time, threshold. management However, of nem Guardianrootstock is9407-14 resistant is toresistant ring and to root-knotmany PPNs. nema - management of nematodes is important as they todes,Some PeachNemagard rootstocks is resistant are resistant to root-knot to nematodes: nema- are a predisposing factor to soil borne pathogen tode, and Schwarzmann and Freedom rootstocks infection and environmental stresses such as win- were rated as resistant against X. index. Adaptive ter cold injury, spring frost injury, salt injury and/ studies of such rootstocks to our local condition are underway. infectious state, not the males. or micronutrient deficiency. Young females are the in western Colorado, especially targeted to replant living nematodes as they control many different disease.The integrated use of bio-fumigation is under study Provide enough organic matter to increase the free free living nematodes, add soil with a higher num- References: PPNs in the soil. If your soil does not have enough- and management of phytoparasitic nematodes in west- ber of free living nematodes and provide food (or Pokharel, R. R. and H. J. Larsen. 2007. The importance ganic matter) to these nematodes.Brassica spp. can be used ern Colorado fruit orchards. Journal of Nematology 39(1): 96. - Marigold, sudan grass and todes associated with fruit crops in western Colorado. free living nematode populations in the soil. Gluco- Pokharel,Western R. Colorado and H. J. ResearchLarsen. 2008. Center, Plant Colorado parasitic State nema Uni- sinilateas green or manure isocthiocyanate crops to control content PPNs in many and Brassicaboost versity. Western Colorado Research Center, Colorado

State University. Annual report, TR 07-08: 22-28. - Soilspecies solarization is known is to very control effective many for PPNs. control of many nematodes and other soilborne pathogens. Mai, W. F. and Peter Mullin. 1975. Plant-Parasitic Nema todes. A Pictorial Key to Genera. Fourth edition. PP 277 by Comstock Publishing Associates, a division of Cornell Univ Ithaca and London. For soil solarization: plow field to ensure looseness,

40 Utah-Colorado Tree Fruit Production Guide Chapter 5: Pesticide Tables chapter 5 Pesticide tables

Restricted Entry and Pre-Harvest Intervals

PHI (days) Formulation Name REI nectar- (Active Ingredient Name) Type (hrs) apple pear cherry peach ine apricot plum

Abound (azoxystrobin) F 4 ------0 0 0 0 0 Pesticide Tables Acramite-50WS (bifenazate) I 12 7 7 3 3 3 3 3 Actara (thiamethoxam) I 12 14/35 14/35 14 14 14 14 14 Adament 50 WG (tebuconazole+ F 12 75 75 1 1 1 1 1 trifloxystrobin) Admire Pro (imidacloprid) I 12 7 7 7 0 0 0 7 Admire Pro (soil application) I 12 21 21 21 21 21 21 21 Agree WG (Bacillus thruingiensis) I 4 0 0 0 0 0 --- 0 Agri-Flex (thiamethoxam+ I 12 35 35 ------abamectin) Agri-Fos (mono- and dibasic sodium, F 4 NL NL NL NL NL NL NL potassium, and ammonium phosphites) Agri Star Basic Copper 53 (basic F 24 0 0 0 0 0 0 0 copper sulfate) Agri-Mek 0.15EC (abamectin) I 12 28 28 21 21 21 21 21 Agri-Mycin 17 (streptomycin) F 12 50 30 ------Aim EC (carfentrazone) H 12 3 3 3 3 3 3 3 Aliette WDG (aluminum tris) F 12 14 14 NLa NLa NLa NLa NLa Allityn (garlic juice extracts) I 4 12 hrs 12 hrs 12 hrs 12 hrs 12 hrs 12 hrs 12 hrs Altacor (chlorantraniliprole) I 4 5 5 10 10 10 10 10 Ambush 25W (permethrin) I 12 NLb NLc 3 14 ------Amine 4, Saber, others (2,4-D H 48 14 14 40 40 40 40 40 amine) Apollo SC (clofentezine) I 12 45 21 21 21 21 21 --- Asana XL (esfenvalerate) I 12 21 28 14 14 14 14 14 Assail 30 SG/70WP (acetamiprid) I 12 7 7 7 7 7 7 7 Avaunt (indoxacarb) I 12 14 28 14 14 14 14 14 Aza-Direct (azadirachtin) I 4 NLd NLd 0 0 0 0 0 Azatin XL (azadirachtin) I 4 0 0 0 0 0 0 0 Baythroid XL (beta-cyfluthrin) I 12 7 7 7 7 7 7 7 Belay (clothianidin) I 12 7 7 --- 21 ------Beleaf 50 SG (flonicamid) I 12 21 21 14 14 14 14 14 Belt SC (flubendiamide) I 12 14 14 7 7 7 7 7 Biomite (Citronellol, Farnesol, I 4 NL NL NL NL NL NL NL Geraniol, Nerolidol) BlightBan A506 (Pseudomonas F 4 NL NL NL NL NL NL --- fluorescens)

NL = no time listed c = dormant/pre-bloom only f = not labeled for Colorado I = insecticide a = non-bearing trees only d = do not apply after pink stage g = do not apply after shuck split F = fungicide b = do not apply after petal fall e = dormant/delayed-dormant only --- = not labeled H = herbicide

Utah-Colorado Tree Fruit Production Guide 41 Chapter 5: Pesticide Tables

Restricted Entry and Pre-Harvest Intervals, continued

PHI (days) Formulation Name REI nectar- (Active Ingredient Name) Type (hrs) apple pear cherry peach ine apricot plum Botanigard 22WP (Beauveria I 4 0 0 0 0 0 0 0 bassiana strain GHA) Bravo Ultrex/Weather Stik F 12 ------g g g g g (chlorothalonil) NL NL NL NL NL Bugitol (capsaicin, allyl I 4 0 0 0 0 0 0 0 isothiocyanate) Tables Pesticide Pesticide Cabrio EG (pyraclostrobin) F 12 ------0 ------Calypso (thiacloprid) I 12 30 30 ------Captan 50 WP (captan) F 24 0 NL 0 0 0 0 0 Carpovirusine (codling moth I 12 0 0 ------granulosis virus) Carzol SP (formetanate I 5 days b b --- b b ------hydrochloride) NL NL NL NL Casoron 4G (granular) H 12 NL NL NL NL NL NL NL (dichlobenil) Centaur WDG (buprofezin) I 12 14 14 14 14 14 14 14 Champ Dry Prill, Champ Formula F 24 e e e 21 21 e e 2, Champ WG (copper hydroxide) NL NL NL NL NL Chateau WDG (flumioxazin) H 12 60 60 60 60 60 60 60 Clutch 50 WDG (clothianidin) I 12 7 7 ------CYD-X (codling moth granulosis I 4 0 0 ------0 virus) Danitol 2.4 EC (fenpropathrin) I 24 14 14 3 3 3 3 3 Delegate WG (spinetoram) I 4 7 7 7 14 1 14 7 Deliver (Bacillus thruingiensis) I 4 0 0 0 0 0 0 0 Devrinol 50-DF (napropamide) H 12 35 35 35 35 35 35 35 Diazinon 50W (diazinon) I 4 21 21 21 21 21 21 21 Dicofol 4E (dicofol) I 35 days 7 7 ------Dimethoate 2.67, Dimethoate 4EC 10-14 I --- 28 21f ------(dimethoate) days Dimilin 2L (diflubenzuron) I 12 --- 14 --- NLb NLb NLb NLb Dipel DF (Bacillus thruingiensis) I 4 0 0 0 0 0 0 0 Ecozin (azadirachtin) I 4 0 0 0 0 0 0 0 Elite 45 WP (tebuconazole) F 12 ------0 0 0 ------Endigo ZC (thiamethoxam+ I 24 35 35 14 14 14 14 14 lambda-cyhalothrin) Entrust (spinosad) I NL 7 7 7 14 14 14 7 Envidor 2 SC (spirodiclofen) I 12 7 7 7 7 7 7 7 Esteem 35 WP (pyriproxyfen) 12 45 45 14 14 14 14 14 Flint (trifloxystrobin) F 12 14 14 1 ------

NL = no time listed c = dormant/pre-bloom only f = not labeled for Colorado I = insecticide a = non-bearing trees only d = do not apply after pink stage g = do not apply after shuck split F = fungicide b = do not apply after petal fall e = dormant/delayed-dormant only --- = not labeled H = herbicide

42 Utah-Colorado Tree Fruit Production Guide Chapter 5: Pesticide Tables

Restricted Entry and Pre-Harvest Intervals, continued

PHI (days) Formulation Name REI nectar- (Active Ingredient Name) Type (hrs) apple pear cherry peach ine apricot plum Fosphite (salts of phosphorous F 4 0 0 0 0 0 0 0 acid) FujiMite 5EC (fenpyroximate) I 12 14 14 ------

Fusilade DX (fluazifop-P) H 12 60 60 60 60 60 60 60 Pesticide Tables non- non- non- non- non- non- non- Gallery 75 (isoxaben) H 12 bearing bearing bearing bearing bearing bearing bearing Garlic Barrier AG+ (garlic juice) I 4 NL NL NL NL NL NL NL Gem 500 SC (trifloxystrobin) F 12 ------1 1 1 1 1 GF-120 NF (spinosad) I 4 0 0 0 0 0 0 0 Glyphosate (glyphosate) H 12 1 1 17 17 17 17 17 Goal 2XL (oxyfluorfen) H 24 NL NL NL NL NL NL NL Golden Pest Spray Oil (soybean I 4 NL NL NL NL NL NL --- oil) Gramoxone SL (paraquat) H 12 NL NL 28 14 28 28 28 14-15 Guthion Solupak (azinphos methyl) I 14-21 14-21 15 ------days Imidan 70-W (phosmet) I 3 days 7 7 7 14 14 14 7 (tart only) Indar 2F (fenbuconazole) F 12 14 --- 0 0 0 0 0 Inspire Super MP (difenoconazole) F 12 72 72 ------Intrepid 2F (methoxyfenozide) I 4 14 14 7 7 7 7 7 Javelin WG (Bacillus thruingiensis) I 4 0 0 0 0 0 0 0 Kaligreen (potassium bicarbonate) F 4 1 1 1 1 1 1 1 Kanemite 15 SC (acequinocyl) I 12 14 14 ------Karmex DF (diuron) H 12 NL NL --- 20 ------Kelthane 50WSP (dicofol) I 48 7 7 ------Kerb 50-W (pronamide) H 24 NL NL NL NL NL NL NL Kocide 3000 (copper hydroxide) F 24 0 0 0 0 0 0 0 3-4 Lannate SP (methomyl) I 14 ------4 ------days Leverage 360 (imidacloprid+ I 12 7 7 7 7 7 7 7 cyfluthrin) Lorsban-4E (chlorpyrifos) I 4 days NLe NLe NLe NLe NLe --- NLe Malathion 5 EC (malathion) I 12 ------3 7 7 7 --- Matrix FNV (rimsulfuron) H 4 7 7 14 14 14 14 14 Milstop (potassium bicarbonate) F 1 0 0 --- 0 --- 0 0 M-Pede (potassium salts of fatty I 12 0 0 0 0 0 0 0 acids) (tart only) Mycoshield (oxytetracycline) F 12 60 60 --- 21 21 ------Neemix 4.5 (azadirachtin) I 12 NL NL NL NL NL NL NL

NL = no time listed c = dormant/pre-bloom only f = not labeled for Colorado I = insecticide a = non-bearing trees only d = do not apply after pink stage g = do not apply after shuck split F = fungicide b = do not apply after petal fall e = dormant/delayed-dormant only --- = not labeled H = herbicide

Utah-Colorado Tree Fruit Production Guide 43 Chapter 5: Pesticide Tables

Restricted Entry and Pre-Harvest Intervals, continued

PHI (days) Formulation Name REI nectar- (Active Ingredient Name) Type (hrs) apple pear cherry peach ine apricot plum Nexter (pyridaben) I 24 25 25 7 14 14 ------Nordox 75 WG (cuprous oxide) F 24 NL NL NL NL NL NL NL 2-5 Omite-30WS (propargite) I ------NL --- 14 ------days Onager (hexythiazox) I 12 28 28 7 7 7 7 7

Tables Orbit (propiconazole) F 12 ------0 0 0 0 0 Pesticide Pesticide Phostrol (salts of phosphorous F 4 NL NL NL NL NL NL NL acid) Poast (sethoxydim) H 12 14 14 25 25 25 25 25 Portal (fenpyroximate) I 12 14 14 ------Pounce 3.2 EC (permethrin) I 12 NLb NLe 3 14 14 ------Princep 4L (simazine) H 12 150 150 150 NL NL NL NL Pristine (boscalid+pyraclostrobin) F 12 0 0 0 0 0 0 0 Proaxis (gamma-cyhalothrin) I 24 21 21 14 14 14 14 14 Procure 50WS (triflumizole) F 12 14 14 1 ------non- non- non- non- non- non- non- Prowl 3.3 EC (pendimethalin) H 24 bearing bearing bearing bearing bearing bearing bearing Quash (metconazole) F 12 ------14 14 14 14 14 Quilt Xcel (azoxystrobin+ F 12 ------0 0 0 0 0 propiconazole) Quintec (quinoxyfen) F 12 ------7 ------Rally 40WSP (myclobutanil) F 24 14 --- 0 0 0 0 0 Regalia (extract of Reynoutria F 4 0 0 0 0 0 0 0 sachalinensis) non- non- non- non- non- non- non- Reglone 2L (diquat) H 24 bearing bearing bearing bearing bearing bearing bearing Ridomil Gold SL (mefenoxam) F 48 NL --- NL NL NL NL NL Rimon 0.83EC (novaluron) I 12 14 ------8 8 8 8 Rovral 4 F (iprodione) F 24 ------NLb NLb NLb NLb NLb Rubigan E.C. (fenarimol) F 12 30 30 0 ------Savey 50 DF (hexythiazox) I 12 28 28 28 28 28 28 28 Scythe 4.2E (pelargonic acid) H 12 NL NL NL NL NL NL NL non- non- non- non- non- non- non- Select 2EC (clethodim) H 24 bearing bearing bearing bearing bearing bearing bearing Serenade ASO, Serenade MAX F 4 0 0 0 0 0 0 0 (Bacillus subtilis) Sevin 4F, Sevin 80S (carbaryl) I 12 3 3 3 3 3 3 3 Showcase (triflualin+isoxaben+ non- non- non- non- non- non- non- H 24 oxyfluoren) bearing bearing bearing bearing bearing bearing bearing Sinbar (terbacil) H 12 60 60 60 60 60 60 60

NL = no time listed c = dormant/pre-bloom only f = not labeled for Colorado I = insecticide a = non-bearing trees only d = do not apply after pink stage g = do not apply after shuck split F = fungicide b = do not apply after petal fall e = dormant/delayed-dormant only --- = not labeled H = herbicide

44 Utah-Colorado Tree Fruit Production Guide Chapter 5: Pesticide Tables

Restricted Entry and Pre-Harvest Intervals, continued

PHI (days) Formulation Name REI nectar- (Active Ingredient Name) Type (hrs) apple pear cherry peach ine apricot plum Snapshot 2.5TG non- non- non- non- non- non- non- H 12 (isoxaben+trifluralin) bearing bearing bearing bearing bearing bearing bearing Solicam DF (norflurazon) H 12 60 60 60 60 60 60 60

Sonata (Bacillus pumilis) F 4 0 0 0 0 0 0 0 Pesticide Tables Sovran (kresoxim-methyl) F 12 30 30 ------SpinTor 2SC (spinosad) I 4 7 7 7 14 1 14 7 Sporan EC (rosemary, clove, and F 0 0 0 0 0 0 0 0 thyme oils) Stinger (clopyralid) H 12 30 30 30 30 30 30 30 Success (spinosad) I 4 7 7 7 1 1 14 7 SucraShield (sucrose octanoate I 48 0 0 0 0 0 0 0 esters) Sulforix (calcium polysulfide) F 48 NL NL NL NL NL --- NL Supracide 2E (methidathion) I 3 days NLe NLe NLe NLe NLe NLe NLe Surflan AS (oryzalin) H 24 NL NL NL NL NL NL NL Surround WP (kaolin clay) I NL 0 0 ------Syllit FL (dodine) F 48 7 7 7 15 ------Thionex 50W (endosulfan) I 20 days 21 20 21 21/30 21/30 ------(sweet) -Thionex 50W can not be used on peaches, nectarines, or cherries after July 31, 2012. 80% Thiosperse (sulfur) F 24 NL NL NL NL NL --- NL Thiram Granuflo (thiram) F 24 ------7 ------Topsin M 70 WDG (thiophanate- 12h /3 F 1 1 1 1 1 1 1 methyl) days Tourismo I 12 14 14 14 14 14 14 14 (flubendiamide+buprofezin) Trilogy (clarified hydrophobic F 4 0 0 0 0 0 0 0 extract of neem oil) Ultor (spirotetramat) I 24 7 7 7 7 7 7 7 Vangard WG (cyprodinil) I 12 72 72 2 2 2 2 2 (tart only) Vegol (canola oil) I NL NL NL NL ------Vendex 50WP (fenbutatin-oxide) I 48 14 14 14 14 14 --- 14 Venue (pyrafluven ethyl) H 12 NL NL NL NL NL NL NL Virosoft (codling moth granulosis I 4 NL NL ------NL virus) Voliam Flexi (thiamethoxam/ I 12 35 35 14 14 14 14 14 chlorantraniliprole) Voliam Xpress (lambda-cyhalothrin I 24 21 21 14 14 14 14 14 +chlorantraniliprole) Warrior (lambda-cyhalothrin) I 24 21 21 14 14 14 14 14 Zeal (etoxazole) I 12 28 28 ------Ziram 76DF (ziram) F 48 14 14 30 30 30 30 ---

NL = no time listed c = dormant/pre-bloom only f = not labeled for Colorado I = insecticide a = non-bearing trees only d = do not apply after pink stage g = do not apply after shuck split F = fungicide b = do not apply after petal fall e = dormant/delayed-dormant only --- = not labeled H = herbicide

Utah-Colorado Tree Fruit Production Guide 45 Chapter 5: Pesticide Tables

Pesticide Toxicity to Honeybees and Pollinators

The following steps can help to protect honeybees and control operations. Tests have shown that at pollinators in the orchard. maximum dosage, 2,4-D alkanolamine salts and isopropyl esters and similar herbicides, are more Choose the least toxic insecticide possible. toxic than other forms. Oily formulations seem to be more hazardous to bees. Spraying in late after- • Do not spray trees in bloom noon or evening will also lessen the hazard, since • Apply insecticides in late evening, night, or early bees will not visit the blooms after they become morning while bees are not actively foraging. • curled. Even if trees are not in bloom, plenty of plants are Tables

Pesticide Pesticide Blossom-thinning sprays have not been hazardous applications are generally less hazardous to bees to bees in orchards. However, Sevin used as a fruit blooming on the orchard floor or border. Evening • than early morning applications. Bees can be con- thinner 15 to 25 days past full bloom of apples sidered to be active when temperatures are above is highly hazardous if cover crop blooms become 52°F. contaminated. Contact the beekeeper or the county bee inspector Take advantage of the delayed dormant timing, to make him or her aware of the pesticide applica- when bees are not active, for many insect pests. • • tion, the type of pesticide, and the area of applica- Learn about the beekeeper’s problems with the tion. poisoning of bees and enter into mutually advanta- • Select herbicide formulations that are the least geous agreements with him or her to best produce harmful to bees for roadside and other weed bee-pollinated crops. •

46 Utah-Colorado Tree Fruit Production Guide Chapter 5: Pesticide Tables

Pesticide Toxicity to Honeybees and Pollinators, continued

Toxicity to beneficial species lady parasitoid predatory honeybees syrphid flies Insecticide (active ingredient) beetles wasps mites Acramite-50WS (bifenazate) ++ + --- + --- Actara (thiamethoxam) ++++ +++ +++ + --- Agri-Flex (thiamethoxam+ abamectin) ++++ + --- +++ --- Pesticide Agri-Mek 0.15EC (abamectin) +++ + --- ++++ --- Tables Allityn (garlic juice extracts) + + + + + Altacor 35WDG (chlorantraniliprole) + + + + --- Ambush 25WP (permethrin) ++++ ++++ --- ++++ --- Apollo 4SC (clofentezine) + + --- + --- Asana 0.66EC (esfenvalerate) ++++ ++++ ++++ ++++ --- Assail 30SG (acetamiprid) ++ +++ ++++ ++++ --- Assail 70WP (acetamiprid) ++ +++ ++++ ++++ --- Avaunt 30DG (indoxacarb) ++ ++++ ++++ + --- Aza-Direct 1.2%L (azadirachtin) ++ + + + --- Azatin (azadirachtin) + + --- + --- Bacillus thuringiensis + + --- + --- Baythroid XL (beta-cyfluthrin) ++++ ++++ --- ++++ --- Belay (clothianidin) ++++ ++ --- + --- Beleaf 50SG (flonicamid) + ------+ --- Belt 4SC (flubendiamide) ++++ + + + ---

Biomite (Citronellol, Farnesol, Geraniol, Nerolidol) + ------Bugitol (capsaicin, allyl isothiocyanate) ++ ------Calypso 4F (thiacloprid) ++ +++ ++++ + --- Captan 50WP (captan) ++++ ------Carpovirusine (codling moth granulosis virus) + + --- + --- Carzol 92SP (formetanate hydrochloride) +++ +++ --- +++ --- Centaur 70W (buprofezin) + ++ --- + --- Clutch 50WDG (clothianidin) ++++ +++ +++ ++ --- Cyd-X (CM granulosis virus) + + + + --- Danitol 2.4EC (fenpropathrin) ++++ ++++ ++++ ++++ --- ++++= Most Hazardous - Do not apply to blooming crops or weeds. += Reasonably Safe – Can be applied at any time. +++= Hazardous – Apply only during late evening. ---= No information available. ++= Moderately Hazardous – Apply only during late evening or early morning.

Utah-Colorado Tree Fruit Production Guide 47 Chapter 5: Pesticide Tables

Pesticide Toxicity to Honeybees and Pollinators, continued

Toxicity to beneficial species lady parasitoid predatory honeybees syrphid flies Insecticide (active ingredient) beetles wasps mites Delegate 25WG (spinetoram) ++ + + ++++ --- Diazinon 50W (diazinon) ++++ +++ ++++ + --- Dicofol 4E (dicofol) + + --- ++ --- Dimethoate 2.67EC (dimethoate) ++++ +++ --- +++ ---

Tables Dimethoate 4EC (dimethoate) ++++ +++ --- +++ --- Pesticide Pesticide Dimilin 2L (diflubenzuron) + ------Ecozin (azadirachtin) ++ + --- + ---

Endigo ZC (thiamethoxam+ lambda-cyhalothrin) ++++ ++ --- ++ --- Entrust 80W (spinosad) +++ +++ --- + +++ Envidor 2 SC (spirodiclofen) ++++ ++ --- + --- Esteem 35WP (pyriproxyfen) + +++ +++ + --- FujiMite 5%EC (fenpyroximate) + ++ --- + --- Garlic Barrier AG+ (garlic juice) + ------GF-120 0.02% Bait (spinosad) +++ + --- + --- Golden Pest Spray Oil (soybean oil) + ------Guthion 50WP (azinphos methyl) ++++ + --- + --- horticultural oils ++ + ------Imidan 70W (phosmet) ++++ +++ ++++ + --- Intrepid 2F (methoxyfenozide) + + + + --- Kanemite 15SC (acequinocyl) + + --- + --- Lannate SP (methomyl) ++++ ++++ ++++ ++++ --- Leverage (imidacloprid/cyfluthrin) ++++ ++++ --- ++++ --- Lorsban 4E (chlorpyrifos) ++++ + ++ ++ --- Lorsban 75WG (chlorpyrifos) ++++ + ++ ++ --- Malathion (malathion) ++++ +++ +++ ------M-Pede (potassium salts of fatty acids) ++ ------Neemix 4.5%L (azadirachtin) ++ + --- + --- Nexter 75WSB (pyridaben) ++ +++ --- +++ --- Omite 30WS (propargite) + ------Onager 1EC (hexythiazox) + ------+ --- ++++= Most Hazardous - Do not apply to blooming crops or weeds. += Reasonably Safe – Can be applied at any time. +++= Hazardous – Apply only during late evening. ---= No information available. ++= Moderately Hazardous – Apply only during late evening or early morning.

48 Utah-Colorado Tree Fruit Production Guide Chapter 5: Pesticide Tables

Pesticide Toxicity to Honeybees and Pollinators, continued

Toxicity to beneficial species lady parasitoid predatory honeybees syrphid flies Insecticide (active ingredient) beetles wasps mites Pounce 3.2EC (permethrin) ++++ ++++ --- ++++ --- Proaxis 0.5L (gamma-cyhalothrin) ++++ ++++ ++++ ++++ --- Procure (triflumizole) + ------Pesticide Provado 1.6F (imidacloprid) ++++ +++ +++ + --- Tables Portal (fenpyroxymate) + ++ --- + --- Rimon 0.83EC (novaluron) ++++ ++++ +++ ++++ --- Rovral 4F (iprodione) ++++ ------Rovral 50W (iprodione) ++++ ------Rubigan (fenarimol) + ------Savey 50DF (hexythiazox) + + --- + --- Sevin 4F (carbaryl) ++++ +++ ++++ +++ --- Sevin 80S (carbaryl) ++++ +++ ++++ +++ --- Spintor (spinosad) ++ ++ + ++ --- Success 2F (spinosad) ++ +++ --- +++ +++ SucraShield (sucrose octanoate esters) + ------Sulforix (lime sulfur/calcium polysulfide) + ------sulfur, wettable + ------Supracide 2E (methidathion) ++++ ------Surround WP (kaolin clay) + + --- ++ --- Thionex (endosulfan) +++ ++ --- + --- Tourismo (flubendiamide/buprofezin) + ++ --- + --- Ultor (spirotetramat) + ------+++ --- Vegol (canola oil) + ++ --- ++ --- Vendex 50WP (fenbutatin oxide) + + --- ++ --- Virosoft (codling moth granulosis virus) + + --- + ---

Voliam Flexi (thiamethoxam+chlorantraniliprole) ++++ +++ ++++ ++ --- Voliam Xpress (lambda-cyhalothrin+chlorantrani ++++ ++++ --- ++++ --- liprole) Warrior (lambda-cyhalothrin) ++++ ++++ ++++ ++++ --- Zeal 72WDG (etoxazole) + ------+++ --- ++++= Most Hazardous - Do not apply to blooming crops or weeds. += Reasonably Safe – Can be applied at any time. +++= Hazardous – Apply only during late evening. ---= No information available. ++= Moderately Hazardous – Apply only during late evening or early morning.

Utah-Colorado Tree Fruit Production Guide 49 Chapter 5: Pesticide Tables

Insecticide Classes

Main Group and Chemical Sub-group or Active Ingredients Primary Site of Action primary Active Ingredient 1: Acetylcholinesterase inhibitors 1A - Carbamates carbaryl, formetanate hydrochloride Nerve action azinphos methyl, chlorpyrifos, diazinon, 1B - Organophosphates dimethoate, malathion, phosmet 2: GABA-gated chloride channel antagonists 2A - Cyclodiene organochlorines endosulfan Nerve action 3: Sodium channel modulators esfenvalerate, fenpropathrin, gamma-cyha- 3A - Pyrethroids, Pyrethrins Nerve action lothrin, lambda-cyhalothrin, permethrin Tables Pesticide Pesticide 4: Nicotinic acetylcholine receptor agonists acetamiprid, clothianidin, imidacloprid, 4A - Neonicotinoids Nerve action thiacloprid, thiamethoxam 5: Nicotinic acetylcholine receptor activators 5 - Spinosyns spinetoram, spinosad Nerve action 6: Chloride channel activators 6 - Avermectins, Milbemycins abamectin Nerve and muscle action 7: Juvenile hormone mimics 7C - Pyriproxyfen pyriproxyfen Growth regulation 9: Selective homopteran feeding blockers 9C - Flonicamid flonicamid 10: Mite growth inhibitors 10A - Clofentezine, Hexythiazox clofentezine, hexythiazox Growth regulation 10B - Etoxazole etoxazole 11: Microbial disruptors of insect midgut 11 - Bacillus thuringiensis Bacillus thuringiensis Membranes 12: Inhibitors of mitochondrial ATP synthase 12B - Organotin miticides fenbutatin oxide Energy metabolism 12C - Propargite propargite 15: Inhibitors of chitin biosynthesis, type 0 15 - Benzoylureas diflubenzuron, novaluron Growth regulation 16: Inhibitors of chitin biosynthesis, type 1 16 - Buprofezin buprofezin Growth regulation 18: Ecdysone receptor agonists 18 - Diacylhydrazines methoxyfenozide Growth regulation 20: Mitochondrial complex III electron transport inhibitors 20B - Acequinocyl acequinocyl Energy metabolism 21: Mitochondrial complex I electron transport inhibitors 21A - METI acaricides and insecticides fenpyroximate, pyridaben Energy metabolism 22: Voltage-dependent sodium channel blockers 22A - Indoxacarb indoxacarb Nerve action 23: Inhibitors of acetyl CoA carboxylase. 23 - Tetronic and Tetramic acid spirodiclofen, spirotetramat Lipid synthesis, growth regulation derivatives 28: Ryanodine receptor modulators 28 - Diamides chlorantraniliprole, flubendiamide Nerve and muscle action UN: Compounds of Unknown or uncertain mode Target protein responsible for biological azadirachtin, bifenazate, dicofol of action activity is unknown,

50 Utah-Colorado Tree Fruit Production Guide Chapter 5: Pesticide Tables

Fungicide Classes

Main Group and Chemical Sub-group or Active Ingredients Primary Site of Action primary Active Ingredient 1: MBC - fungicides (Methyl Benzimidazole Carbamates) Benzimidazoles, Thiophanates thiophanate-methyl Mitosis 2: Dicarboximides Dicarboximides iprodione Pesticide

NADH signaling Tables 3: DMI-fungicides (DeMethylation difenoconazole, fenarimol, Inhibitors) fenbuconazole, metconazole, DMI-fungicides Sterol biosynthesis myclobutanil, propiconazole, tebuconazole, triflumizole 4: PA – fungicides (Phenyl Amides) PA - fungicides (Phenyl Amides) mefenoxam RNA polymerase 7: SDHI (Succinate dehydrogenase inhibitors) Carboxamides boscalid Respiration 9: AP - fungicides (Anilino-Pyrimidines) AP - fungicides (Anilino- cyprodinil Methionine biosynthesis Pyrimidines) 11: QoI-fungicides (Quinone outside Inhibitors) QoI-fungicides (Quinone outside azoxystrobin, kresoxim-methyl, Inhibitors) pyraclostrobin, trifloxystrobin Respiration 13: Azanaphthanlenes Quinolines quinoxyfen Signal transduction 25: Glucopyranosyl antibiotic Glucopyranosyl Antibiotic streptomycin Protein synthesis 33: Phosphonates salts of phosphorous acid, aluminum Phosphonates Unknown tris 41: Tetracycline antibiotic Tetracycline Antibiotic oxytetracycline Protein synthesis M: Multi-site contact activity M1 - Inorganic copper hydroxide, fixed copper Contact M2 - Inorganic sulfur M3 - Dithiocarbamates and thiram, ziram Relatives M4 - Phthalimides captan M5 - Chloronitriles (Phthalonitriles) chlorothalonil M7 - Guanidines dodine

Utah-Colorado Tree Fruit Production Guide 51 Chapter 5: Pesticide Tables

Spray Incompatibility

Spray Incompatibilities Risk of Phytotoxicity

Aliette plus products containing copper should M-Pede – may be phytotoxic never be mixed. If Aliette is to be applied after or before copper containing compounds, the pH of Abound (azoxystrobin) is highly phytotoxic to cer- the Aliette spray should be raised to 6.0 or above to tain apple varieties. avoid phytotoxicity from solubilized copper. Copper products Bordeaux mixture is not compatible with Bt, Tables

Pesticide Pesticide captan, carbaryl, Carzol, diazinon, dimethoate, Some horticultural oils endosulfan, malathion, provado, pyrethroids, Surround, Syllit, or Vendex. Calcium chloride, calcium nitrate - These materi- als can russet apple, mark pear fruit, and burn leaves Bt is not compatible with Bordeaux mixture, following application depending upon concentra- diazinon, or sulfur. tion, temperature, and number of applications.

Fixed copper is not compatible with Topsin. Captan + oil may cause injury to leaves or fruit when combined in the same spray or applied within Lime is not compatible with azinphos-methyl, 7 - 10 days of an oil spray, particularly after a frost or captan, carbaryl, carzol, dimethoate, endosulfan, during slow drying conditions. imidan, malathion, provado, pyrethroids, Syllit, or Topsin. Captan + Sulfur is phytotoxic to apples.

Oil is not compatible with captan or sulfur. Imidan is phytotoxic to sweet cherry.

Surround is not compatible with Bordeaux mix- ture or sterol inhibitors.

52 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

Chapter 6 pest Management pesticide recommendations

APPLE Pest Phenology Calendar Stages of Development

Half- Petal Post Bloom / Summer Green Tight Full Post Major Dormant inch Pink Fall Tip Cluster Bloom June July August Sept. Harvest Pests Green (May) Aphids (green Eggs on

apple & rosy Nymphs, winged and wingless adults on new growth Eggs on limbs Apple limbs apple) Nymphs on blooms Nymphs, adults (predators), Eggs in Campylomma Eggs in wood and fruit Eggs on leaves wood

Codling Moth Larvae under bark Pupae Adults, eggs, larvae in fruit Larvae under bark

Fire Blight Overwinters in cankers Ooze from cankers is primary source, secondary spread flower to flower

Iron Early spring soil treatments most effective; difficult to control with foliar summer sprays Chlorosis

Phytophthora Root & Collar Zoospores active during entire season when water is present Rot Powdery Fungus overwinters in Active when buds first open Conidia spread during summer Mildew buds

Adults, crawlers, immatures on limbs, Immatures on San Jose Scale Immatures on limbs leaves, & fruit limbs Migrate Adults at base of to Spider Mites Eggs / immatures / adults on ground cover and tree leaves Adults tree ground- cover Western Adults and eggs in Larvae and adults on fruit and Adults on ground Adults Flower Thrips blooms and on leaves leaves

White Apple Nymphs, adults, eggs on Eggs in wood Nymphs on leaves Eggs in wood Leafhopper leaves

Woolly Apple Migrate Colonies start growing Aphid to roots

Utah-Colorado Tree Fruit Production Guide 53 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments GREEN TIP TO HALF-INCH GREEN (Delayed Dormant) Conventional: Aphid eggs 2% horticultural oil alone R (Green apple Lorsban-4E (chlorpyrifos) + horticultural oil See label 3 1 is effective at killing and Rosy apple Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 3 3/28 overwintering eggs. aphids) Reduced Risk/Organic: Beleaf 50 SG (flonicamid) 2-2.8 oz 3 9 horticultural oilO 2% 3 NC

Pest Biology: Scouting/Threshold: Cultural: • aphids overwinter as eggs on • look for dark colored eggs under buds • avoid applying excess nitrogen

Apple limbs and in cracks and crevices fertilizer; causes excess shoot growth that attracts aphids

Conventional: Crown and Aliette WDG: max 5.0 root rot Aliette WDG (aluminum tris) 2.5-5.0 lb 2 33 lb/acre/application and 20 (Phytophthora) Ridomil Gold SL (mefenoxam) 2 qt. 3 4 lb/season.

Reduced Risk/Organic: Fosphite, Phostrol, Fosphite (phosphorous acid) 1-3 qt/100 gal 2 33 Aliette: apply as foliar spray as a protectant; will Phostrol (phosphorous acid) 2.5-5.0 pt 2 33 not “cure” already infected trees. Repeat 2-4 times per year as necessary (every 60 days). Do not apply to dormant trees.

Ridomil Gold SL: apply in early spring and/or after harvest for best results. Use as a soil drench around trunk following labeled rate. Pest Biology: Scouting/Threshold: Cultural: • Phytophthora girdles the cambium, • watch for trees that have delayed • remove dead/dying tree(s); do not causing wilt, limb dieback, and bud break or that develop purple leaf replant in the same site without tree death in wet, poorly drained color early (Aug. - early Sept.) improving drainage; avoid soils excessive irrigation

European Reduced Risk/Organic: red mite and Golden Pest Spray OilO (soybean oil) 4-6 gal 3 NC Brown mite horticultural oilO 2% 4 NC

(these pests rarely need treatment) Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs in cracks • look for red eggs on the bark of • none and crevices on bark scaffolds and twigs

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 54 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments GREEN TIP TO HALF-INCH GREEN (Delayed Dormant) (continued) Conventional: Fire blight Using copper after delayed Champ Dry Prill, Champ Formula 2, Kocide See label 3 M1 dormant stage may cause 101 (copper hydroxide) russeting.

Reduced Risk/Organic: Champ Dry Prill: apply Champ WGO (copper hydroxide) See label 3 M1 as a full cover spray between silver-tip and C-O-C-S WDG (copper oxychloride) 2-4 lb 2 M1 green-tip. Cuprofix (copper sulfate) 5-7.5 lb 2 M1 O Nordox 75 WG (cuprous oxide) 5-10 lb 3 M1 Champ Formula 2: use Apple on yellow varieties may cause discoloration.

Kocide 101: the addition of 1 to 3 lb of hydrated lime per pound of Kocide 101 may reduce crop injury. Pest Biology: Scouting/Threshold: Cultural: • bacteria overwinter in cankers • as temperatures warm, look for • prune limbs infected with cankers in the orchard; cankers oozing cankers, which will indicate 8-10” below visible canker start to ooze bacteria when that the disease has become active margins in late winter or early temperatures warm to 55-60 F spring, before weather warms

San Jose scale horticultural oil + one of the following: 2% 4 NC Golden Pest Spray Oil, Conventional: Vegol: use alone (do not Lorsban-4ER (chlorpyrifos) 1.5-4.0 pt 4 1 mix with horticultural oil). Supracide 2ER (methidathion) See label 4 1 Supracide 2E: sale of this product to be Reduced Risk/Organic: cancelled in December Centaur WDG (buprofezin) 34.5 oz 1 16 2014. Esteem 35 WP (pyriproxyfen) 4-5 oz 3-4 7 Golden Pest Spray OilO (soybean oil) 4-6 gal 2 NC VegolO (canola oil) See label 2 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as black-capped • scale on fruit in previous year • prune out heavily infested limbs immatures on limbs; crawlers indicates need for control hatch in late spring • examine limbs for clusters of gray- white “spots” to determine infestation • delayed dormant timing kills many overwintering nymphs, but not all

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 55 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FIRST PINK Apple scab Conventional: Flint (trifloxystrobin) 2.5 oz 3-4 11 (this pest rarely Procure 50WS (triflumizole) 8-16 oz 4 3 needs treatment Rally 40WSP (myclobutanil) 5-8 oz 4 3 in commercial Rubigan E.C. (fenarimol) 8-12 oz 4 3 orchards) Sovran (kresoxim-methyl) 3.2-6.4 oz 3 11 Vangard WG (cyprodinil) 5 oz 4 9 Ziram 76DF (ziram) 6 lb 4 M3

Reduced Risk/Organic: O

Apple flowable/micronized sulfur See label 3 M2

Pest Biology: Scouting/Threshold: Cultural: • this fungus overwinters on • if scab was present the prior year, • practice good sanitation in fall leaves and fruit on the orchard begin looking for lesions on early with flail mowing of fruit; in small floor; infections occur during developing cultivars first, by examining orchards, remove leaves in fall moisture starting at budbreak 10-20 leaves per 10 trees

Conventional: Powdery Protect susceptible mildew Adament 50 WG (tebuconazole/trifloxystrobin) 4-5 oz 4 3/11 varieties: Gala, Idared, Indar 2F (fenbuconazole) 6-8 oz 4 3 Jonagold, Jonathan, and Inspire Super MP (difenoconazole) + Vangard 4 oz each 4 3/9 Rome. McIntosh and WG (cyprodinil) Golden and Red Delicious Pristine (boscalid/pyraclostrobin) 14.5-18.5 oz 3 7/11 are mildly affected. Procure 50WS (triflumizole) 8-16 oz 4 3 Biologicals (Serenade, Rally 40WSP (myclobutanil) 5-10 oz 4 3 etc.) and oils (Trilogy, Rubigan E.C. (fenarimol) 8-12 oz 3 3 Sporan) must be applied Sovran (kresoxim-methyl) 4.0-6.4 oz 3 11 before infection; they act Sulforix (calcium polysulfide/lime sulfur) 2 qt/100 g 3 M2 as a protectant. Topsin M 70 WDG (thiophanate-methyl) 1.0-1.5 lb 2-3 1 Sovran: 25.6 oz/acre max per season. Reduced Risk/Organic: Flint (trifloxystrobin) 2.0-2.5 oz 4 11 Sulfur: must be reapplied KaligreenO, MilStopO (potassium bicarbonate) See label 3 NC every 7-10 days and may lime-sulfurO See label 3 M2 burn leaves, especially when temps. >90° F. RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC Serenade ASOO (Bacillus subtilis strain QST 713) 2-6 qt 2 NC Serenade MAXO (B. subtilis strain QST 713) 1-3 lb 2 NC SonataO (Bacillus pumilis strain QST 2808) 2-4 qt 2 NC SporanO (rosemary, clove, and thyme oils) 0.5-1 qt/25 g 2 NC Stylet-Oil (paraffinic oil) See label 4 NC 80% ThiosperseO (sulfur) 30 lb 2 M2 TrilogyO (extract of neem oil) See label 2 NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 56 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FIRST PINK (continued) POWDERY MILDEW (continued) Pest Biology: Scouting/Threshold: Cultural: • the fungus overwinters on • apply at half inch green tip stage if • overwinters in buds and infects twigs and in buds and infects powdery mildew was severe the new leaves newly emerging leaves, which previous year then serve as inoculum for later infections

PINK TO PETAL FALL Apple

Campylomma Conventional: Carzol and Assail: apply Carzol SP (formetanate hydrochloride) See label 4 1 at night or while bees are not working in blooms. Reduced Risk/Organic: Do not apply Carzol after petal fall. Assail 70WP (acetamiprid) 1.7-3.4 oz 3-4 4

Pest Biology: Scouting/Threshold: Cultural: • adults are beneficial predators; • shake flower clusters into a cup or • none nymphs may feed on onto a tray to look for light green developing fruit, causing corky nymphs bumps • alternatively, use a beating stick to • nymphs look similar to aphids, dislodge nymphs onto a tray; treat but are faster moving and do when you find 1 nymph/sample on not have cornicles (tailpipes) Golden Delicious and 4 per sample for Red Delicious

BLOOM Reduced Risk/Organic Codling moth Install mating disruption Checkmate CM-O Puffer (Suterra) 1-2 ------just before first moth flight Checkmate CM-XL (Suterra) 200 3 --- (biofix), around full bloom Cidetrak CM (Trece) 400 4 --- of Red Delicious. Isomate-CM Flex (Pacific BioControl) 200-400 4 --- Supplemental insecticides Isomate-C plus (Pacific BioControl) 400 4 --- may be necessary; monitoring with traps is critical. See page 18 for more information. Pest Biology: Scouting/Threshold: Cultural: • moths start emerging from • after mating disruption is hung, install • none pupation around first bloom monitoring traps using Trece CM- of Red Delicious, mate, and lay DA Combo lure. Trap threshold for eggs on leaves and fruit treatment is 10 moths (cumulative capture)

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 57 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments BLOOM (continued) Conventional: Fire blight Biologicals: products Agri-Mycin 17 (streptomycin) 24-48 oz 3-4 25 must be on flowers before Mycoshield (oxytetracycline) 0.5 lb/50 g 2-3 41 infection. Repeat every 5 days during bloom. Reduced Risk/Organic: O repeat BlightBan A506 (Pseudomonas fluorescens A506) See label 2 NC Oxytetracycline: O in 3 days if Cougarblight FireLine 17 WP (oxytetracycline) See label 2-3 41 model recommends. RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC Serenade MAXO (Bacillus subtilis strain QST 2-3 lb 1 NC Streptomycin: in Utah 713) County, use only once per year mixed with Apple oxytetracycline due to resistance. Pest Biology: Scouting/Threshold: Cultural: • when rain occurs and average • check the Cougarblight model • another option is to not spray, temperatures are >60° F, on climate.usu.edu/traps and the but watch for dead terminals 7-14 bacteria may be spread to open CO fruit website for treatment days after bloom, and prune out flowers recommendations immediately

PETAL FALL Conventional: Aphids Actara: do not apply (Green apple Admire Pro (imidacloprid) - foliar application 2.8 oz 4 4 during bloom. and Rosy apple Admire Pro (imidacloprid) - soil application 7-10.5 oz 4 4 aphids) Agri-FlexR (abamectin/thiamethoxam) 5.5-8.5 oz 4 4/6 Admire Pro: max is Calypso 4 F (thiacloprid) 2-4 oz 3 4 10.5 oz/acre per season Clutch 50 WDG (clothianodin) 2-3 oz 4 4 for soil application, 14 oz/ R acre per season for foliar Lannate SP (methomyl) 0.5-1 lb 2-3 1 application. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 3 3/28 Agri-Flex: combining Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 4/28 with oil can russet light- chlorantraniliprole) skinned fruit varieties. Allityn: only an insect Reduced Risk/Organic: repellant; not labeled to Actara (thiamethoxam) 4.5-5.5 oz 3 4 kill. Allityn (garlic juice extracts) See label --- NC Assail 70WP (acetamiprid) 1.1-1.7 oz 3-4 4 Assail 70WP: max 4 O O applications/season. Do Aza-Direct , Azatin XL, Neemix 4.5 See label 2 NC not apply more than once (azadirachtin) every 12 days. Use with Garlic Barrier AG+O (garlic juice) See label 1 NC oil. M-PedeO (potassium salts of fatty acids) See label 2-3 NC

SucraShieldO (sucrose octanoate esters) See label 2 NC Garlic Barrier AG+: insect repellent. Ultor (spirotetramat) 8-14 oz 4 23 VegolO (canola oil) See label 3 NC Lannate SP: do not use on early Macintosh and Wealthy varieties.

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 58 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments PETAL FALL (continued) APHIDS (continued) Pest Biology: Scouting/Threshold: Cultural: • aphids begin hatching at pink • severe infestations of rosy apple aphid • many beneficial insects help stage, and colonies start to may result in deformed fruit; watch suppress aphids, so avoid build fruit for damage throughout the insecticides unless necessary • aphid “stem mothers” give season • avoid excessive nitrogen fertilizer birth to live young as lush growth is attractive to aphids Apple

Borer Conventional: Warrior, Voliam (Shothole, Endigo ZCR (thiamethoxam/lambda-cyhalothrin) 5-6 oz 3 3/4 Xpress: only use if Flatheaded) Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 4/28 absolutely necassary. Pyrethroids harmful to chlorantraniliprole) (minor pests in beneficials. R Colorado and UT) Warrior (lambda-cyhalothrin) 2.5-5 oz 3 3

Pest Biology: Scouting/Threshold: Cultural: • flatheaded and shothole borers • treatments only necessary when • maintain tree health to prevent attack trunks and limbs of borer populations are known to be infestation trees under stress high in an area • prune out dead/dying limbs • prevent infestations in at-risk • look for sawdust-like frass, loose immediately and remove debris trees (young, stressed, or in peeling bark, and exit holes decline) when adults are active from spring - mid summer

Conventional: Fruitworm Avaunt: do not apply (Speckled green Belt SC (flubendiamide) 3-5 oz 4 28 more than 24 oz per acre fruitworm) Imidan 70-W (phosmet) 3.5-5.33 lb 2 1 per crop. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 (this pest rarely Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 3 3/28 Deliver, Dipel: must be applied when larvae are needs treatment in Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 4 4/28 Colorado or Utah) less than 1/2 inch. chlorantraniliprole) WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 3

Reduced Risk/Organic: Avaunt (indoxacarb) 5-6 oz 2-3 22 DeliverO (Bacillus thuringiensis sub. kurstaki) 0.5-2.0 lb 3 11 DipelO (B. thuringiensis sub. kurstaki) 1-4 pt 3 11 EntrustO, Success (spinosad) See label 3 5

Pest Biology: Scouting/Threshold: Cultural: • spring larvae will damage • examine fruit clusters, take action at • none blooms and leaves; summer 10 larvae per 100 clusters larvae will eat the fruit directly

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 59 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments PETAL FALL (continued) Conventional: Leafrollers Agree WG, Deliver, (European, Belt SC (flubendiamide) 3-5 oz 4 28 Javelin WG: must be fruittree, and Danitol 2.4 EC (fenpropathrin) 16-21.3 oz 4 3 applied when larvae are obliquebanded) Imidan 70-W (phosmet) 3.5-5.3 lb 2 1 less than 1/2 inch. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 max is 4 (these pests rarely Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 3/28 Altacor: need treatment in applications/season (9 Colorado or Utah) oz per crop per acre per Reduced Risk/Organic: year). Agree WGO (Bacillus thuringiensis sub. aizawai) 1-2 lb 3 11 Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Bugitol: apply 96 oz/100 gal per acre for heavy Apple O O See label 1 UN Aza-Direct , Azatin XL, Neemix 4.5 infestations. (azadirachtin) Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g 2 NC Delegate WG: max is 4 Delegate WG (spinetoram) 4.5-7 oz 4 5 applications per calendar DeliverO (B. thuringiensis sub. kurstaki strain SA-12) 0.5-2.0 lb 3 11 year, and 29 oz per acre per crop. EntrustO, Success (spinosad) See label 3-4 5 O Garlic Barrier AG+ (garlic juice) See label 1 NC Entrust, Success: toxic Intrepid 2F (methoxyfenozide) 8-16 oz 3 18 to bees for 3 hours after Javelin WGO (B. thuringiensis sub. kurstaki) 0.5-4 lb 3 11 application.

Pest Biology: Scouting/Threshold: Cultural: • fruittree leafrollers overwinter • look for white honeycomb egg masses • often controlled with codling as eggs; obliquebanded on limbs; use beating tray to sample moth sprays overwinter as immatures in for newly hatched larvae protected sites • if using mating disruption for codling moth, leafroller damage may increase to lack of insecticide sprays, so monitor carefully

Conventional: Lygus and Stink Beleaf: max 8.4 oz per bugs Danitol 2.4 EC (fenpropathrin) 16-21.3 oz 4 3 season. Thorough spray Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 coverage is essential.

Reduced Risk/Organic: Beleaf 50SG (flonicamid) 2-2.8 oz 4 9

Pest Biology: Scouting/Threshold: Cultural: • often overwinter in alfalfa or • large numbers of bugs can cause • remove weed host plants other field crops and migrate significant cat-facing damage • do not mow nearby weeds or to nearby fruit trees when • look for adults in weeds and borders cover crops when fruit is present other crops are harvested with sweep nets or the insects will move to the • feeding injury under warm, wet trees conditions can lead to fire blight infections

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 60 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments PETAL FALL (continued) Conventional: Powdery Protect susceptible mildew Indar 2F (fenbuconazole) 6-8 oz 4 3 varieties: Gala, Idared, Inspire Super MP (difenoconazole) + Vangard 4 oz each 4 3/9 Jonagold, Jonathan, and WG (cyprodinil) Rome. McIntosh and Pristine (boscalid/pyraclostrobin) 14.5-18.5 oz 4 7/11 Golden and Red Delicious Procure 50WS (triflumizole) 8-16 oz 4 3 are mildly affected. Rally 40WSP (myclobutanil) 5-10 oz 4 3 Biologicals (Serenade, Rubigan E.C. (fenarimol) 8-12 oz 4 3 etc.) and oils (Trilogy,

Sovran (kresoxim-methyl) 4.0-6.4 oz 3 11 Sporan) must be applied Apple Sulforix (calcium polysulfide/lime sulfur) 2 qt/100 g 3 M2 before infection; they act Topsin M 70 WDG (thiophanate-methyl) 1.0-1.5 lb 2-3 1 as a protectant.

Sovran: 25.6 oz/acre Reduced Risk/Organic: max per season. Flint (trifloxystrobin) 2.0-2.5 oz 3-4 11 KaligreenO, MilStopO (potassium bicarbonate) See label 3 NC Sulfur: must be reapplied lime-sulfurO See label 3 M2 every 7-10 days and may burn leaves, especially RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC when temps. >90° F. Serenade ASOO (Bacillus subtilis strain QST 713) 2-6 qt 2 NC SonataO (Bacillus pumilis strain QST 2808) 2-4 qt 2 NC SporanO (rosemary, clove, and thyme oils) 0.5-1 qt/25 g 2 NC Stylet-Oil (paraffinic oil) See label 4 NC 80% ThiosperseO (sulfur) 30 lb 2 M2 TrilogyO (extract of neem oil) See label 2 NC

Pest Biology: Scouting/Threshold: Cultural: • new foliar infections serve as • check for watersoaked-appearing new • none inoculum for later infections infections

Conventional: Western flower This pest may be a thrips Carzol SP (formetanate hydrochloride) 1-1.25 lb 2-3 1 problem on yellow, pink, and green apple varieties. Reduced Risk/Organic: EntrustO (spinosad) 2-3 oz 4 5 Carzol SP: do not use Success (spinosad) 6-10 oz 4 5 after petal fall.

Pest Biology: Scouting/Threshold: Cultural: • overwinter as adults in on the • shake flower clusters into cup; check 5 • minute pirate bug and green ground and move to trees clusters on each of 5 trees in each 10 lacewings are important during bloom acre block predators • insert eggs into young fruitlet, • treat when more than 2 adults are resulting in “pansy spot” found per cluster

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 61 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments PETAL FALL (continued) Conventional: Western Admire Pro: do not tentiform Admire Pro (imidacloprid) - foliar application 2.8 oz 3 4 apply more than 14 oz/ leafminer Agri-Mek 0.15ECR (abamectin) 10-20 oz 4 6 acre per season for foliar Belt SC (flubendiamide) 3-5 oz 4 28 application. (this pest rarely Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 needs treatment in Agri-Mek 0.15EC: given Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 4 3/28 Utah) rate is for concentrate spray, see label for dilute Reduced Risk/Organic: spray rate. Assail 30 SG (acetamiprid) 2.5 oz 4 4 Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g 2 NC Bugitol: apply 96 oz/100 gal per acre for heavy Apple Success (spinosad) 4-10 oz 3-4 5 infestations.

Pest Biology: Scouting/Threshold: Cultural: • pupae overwinter inside mines • sample leaves for mines beginning in • none in fallen leaves and emerge as mid-June once/wk through Aug.; treat tiny moths in spring if terminals have 1/2–1 mine per leaf

Conventional: White apple Admire Pro: max is leafhopper Admire Pro (imidacloprid) - foliar application 1.4-2.8 oz 4 4 10.5 oz/acre per season Admire Pro (imidacloprid) - soil application 7-10.5 oz 4 4 for soil application, 14 oz/ Calypso 4 F (thiacloprid) 2-4 oz 4 4 acre per season for foliar Carzol SP (formetanate hydrochloride) See label 4 1 application. Clutch 50 WDG (clothianidin) 2-3 oz 4 4 Carzol: do not apply Danitol 2.4 EC (fenpropathrin) 10.3-21.3 oz 3 3 after petal fall. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz --- 3/28 Centaur WDG: limited to one application/year. Reduced Risk/Organic: Assail 30 SG (acetamiprid) 2.5-4.0 oz 3 4 Garlic Barrier AG+: insect repellent. Avaunt (indoxacarb) 5-6 oz 3-4 22 O O Aza-Direct , Azatin XL,Neemix 4.5 See label 1 UN Surround WP: apply (azadirachtin) within 3 days of first petal Centaur WDG (buprofezin) 9-12 oz 3 16 fall or at initial infestation. Garlic Barrier AG+O (garlic juice) See label 1 NC Continue every 7-14 days during infestation period. M-PedeO (potassium salts of fatty acids) See label 2-3 NC O Surround WP (kaolin clay) See label 1 NC Tourismo: max 3 VegolO (canola oil) See label 2 NC applications/season

Pest Biology: Scouting/Threshold: Cultural: • eggs hatch at tight cluster • monitor with beating tray; if • none stage, peaking during bloom population exceeds one nymph per • best to manage nymphs early terminal, treat before older nymphs in the season, as adults are (with long wing pads) are present difficult to control

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 62 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments PETAL FALL (continued) Conventional: Woolly apple Actara: highly toxic to aphid Clutch 50WDG (clothianodin) 2-3 oz 3 4 bees; do not apply during bloom Reduced Risk/Organic: Actara (thiamethoxam) 4.5-5.5 oz 3 4 Assail 70WP: do not apply more than once Assail 70WP (acetamiprid) 1.1-1.7 oz 3-4 4 every 12 days and do Beleaf 50SG (flonicamid) 2-2.8 oz 2-3 9 not exceed more than 4 M-PedeO (potassium salts of fatty acids) See label 2-3 NC applications per season. O SucraShield (sucrose octanoate esters) See label 2 NC For best results use with a Apple Ultor (spirotetramat) 8-14 oz 4 23 horticultural oil. VegolO (canola oil) See label 3 NC Ultor: works best if applied at petal fall.

Pest Biology: Scouting/Threshold: Cultural: • overwinters primarily on roots, • look for white cottony colonies in • many beneficial insects help and colonies start forming on bark cracks and crevices and suckers suppress aphids, so avoid suckers or low in the tree by insecticides unless necessary June; some overwinter in tree canopy

FRUIT PRESENT Conventional: Aphids Admire Pro: max is (Green apple Admire Pro (imidacloprid) - foliar application 2.8 oz 4 4 10.5 oz/acre per season and Rosy apple Admire Pro (imidacloprid) - soil application 7-10.5 oz 4 4 for soil application, 14 oz/ aphids) Calypso 4 F (thiacloprid) 2-4 oz 3 4 acre per season for foliar Clutch 50 WDG (clothianodin) 2-3 oz 4 4 application. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 Assail 70WP: do not Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 3 3/28 apply more than once R Voliam Xpress (lambda-cyhalothrin/ 6-12 oz 3 4/28 every 12 days and do chlorantraniliprole) not exceed more than 4 applications per season. Reduced Risk/Organic: For best results use with a horticultural oil. Actara (thiamethoxam) 4.5-5.5 oz 3 4 Assail 70WP (acetamiprid) 1.1-1.7 oz 3-4 4 Bugitol: apply 96 oz/100 Aza-DirectO, Azatin XL, Neemix 4.5O See label 2 UN gal per acre for heavy (azadirachtin) infestations. Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g 2 NC Garlic Barrier AG+: Garlic Barrier AG+O (garlic juice) See label 1 NC insect repellent. M-PedeO (potassium salts of fatty acids) See label 2-3 NC SucraShieldO (sucrose octanoate esters) See label 2 NC Ultor (spirotetramat) 8-14 oz 4 23 VegolO (canola oil) See label 3 NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 63 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) APHIDS (continued) Pest Biology: Scouting/Threshold: Cultural: • aphid “stem mothers” continue • severe infestations of rosy apple aphid • avoid insecticides unless to give birth to live young may result in deformed fruit; watch necessary to protect beneficials fruit for damage throughout the season

Conventional: Apple maggot Admire Pro: do not apply Admire Pro (imidacloprid) - foliar application 2.8 oz 3 4 more than 14 oz/acre per (This fly is found Asana XL (esfenvalerate) 4.8-14.5 oz 2 3 season for foliar application. Apple in apples from Imidan 70-W (phosmet) 3.5-5.33 lb 3 1 Colorado Springs to Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 Asana XL: given rate is Loveland, CO. It has for concentrate spray, see Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 4 3/28 not been trapped in label for dilute spray rate. commercial orchards chlorantraniliprole) in Colorado or Utah. WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 4 Treatment is needed only in areas where it occurs.) Pest Biology: Scouting/Threshold: Cultural: • overwinters as pupa and flies • hang red sticky sphere traps starting • hawthorn and crabapple are start emerging in mid July, in early July, focusing on the southern alternate hosts; remove them if continuing through September border, or borders next to abandoned they are infested • females lay eggs under apple orchards skin and maggots feed on flesh; • according to Cornell, treat when 5 larger, softer apples are more flies per trap are caught susceptible

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 64 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) Conventional: Codling moth Reapply based on Asana XL (esfenvalerate) 4.8-14.5 oz 2 3 protection intervals on Belt SC (flubendiamide) 5 oz 2-3 28 product labels, keeping Calypso 4 F (thiacloprid) 4-8 oz 3 4 fruit protected through Danitol 2.4 EC (fenpropathrin) 16-21.3 oz 2 4 September 15. Endigo ZCR (thiamethoxam/lambda-cyhalothrin) 5-6 oz 2-3 3/4 R Altacor: max is 4 Guthion Solupak (azinphos-methyl) 2-3 lb 3-4 1 applications/season (9 Imidan 70-W (phosmet) 3.5-5.33 lb 3-4 1 oz per crop per acre per R Leverage 360 (cyfluthrin/imidacloprid) 2.4-2.8 oz 2 3/4 year). Apple Rimon 0.83EC (novaluron) 30-50 oz 3-4 15 Tourismo (buprofezin/flubendiamide) 15-17 oz 3 12/16 Asana XL: given rate is for concentrate spray, see Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 label for dilute spray rate. Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 4 3/28 chlorantraniliprole) Assail 70WP: max is WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 4 4 applications/season. Do not apply more than once every 12 days. For Reduced Risk/Organic: best results, use with a Agree WGO (Bacillus thuringiensis sub. aizawai 1-2 lb 1 11 horticultural oil. strain GC-91) Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Delegate WG: do not Assail 70WP (acetamiprid) 1.7-3.4 oz 3-4 4 apply more than a total of 29 oz per acre per crop. Carpovirusine, Virosoft, Cyd-XO (codling See label 2 NC moth granulosis virus) Entrust: do not apply Delegate WG (spinetoram) 6-7 oz 3-4 5 more than a total of 9 oz DeliverO (B. thuringiensis sub. kurstaki strain SA-12) 0.5-2.0 lb 1 11 per acre per crop. EntrustO (spinosad) 2-3 oz 2-3 5 Guthion: max use is 3 lb/ Esteem 35 WP (pyriproxyfen) 4-5 oz 3 7 acre; use cancelled after O horticultural oil See label 3 NC Sept. 30, 2012. Intrepid 2F (methoxyfenozide) 16 oz 2-3 18 Javelin WGO (B. thuringiensis sub. kurstaki 0.5-4.0 lb 1 11 Tourismo: do not apply strain SA-11) more than 3 times per crop season. Success (spinosad) 6-10 oz 3-4 5

Pest Biology: Scouting/Threshold: Cultural: • codling moth overwinters as • hang pheromone traps to determine • trunk banding and fruit bagging resting larvae and pupate in biofix (first male flight) in your area • remove fruit bins and other spring; emerge as adults at • start sprays 10 days after petal fall or structures from orchards where approx. 100 GDD 220 degree-days after first adult moth larvae can overwinter activity (biofix)

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 65 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) Conventional: Crown and Aliette WDG: max is 5.0 root rot Aliette WDG (aluminum tris) 2.5-5.0 lb 2 33 lb/acre per application and (Phytophthora) 20 lb per season. Reduced Risk/Organic: Phostrol (mono- and dibasic sodium, 2.5-5.0 pt 2 33 Phostrol: apply to potassium, and ammonium phosphites) healthy trees adjacent to diseased trees to increase resistance. Pest Biology: Scouting/Threshold: Cultural: • new infections can occur at any • watch trees for slow growth, small • remove dead/dying tree(s) and time during the growing season fruit, early fall color (red to purple-red do not replant in the same site Apple so long as soil is saturated leaves) without improving drainage; avoid for at least 12-24 hr; can also excessive irrigation. spread via root to root contact.

Conventional: European Zeal: predominately red mite and Envidor 2 SC (spirodiclofen) 16-18 oz 4 23 an ovicide/larvicide and Brown mite Kelthane 50WSP (dicofol) See label 2 UN should be used early in the Onager (hexythiazox) 12-24 oz 4 10 life cycle of mites. (these pests rarely need treatment Reduced Risk/Organic: in commercial BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC orchards) horticultural oilO See label 2-3 NC Kanemite 15 SC (acequinocyl) 21-31 oz 4 20 VegolO (canola oil) See label 2-3 NC Zeal (etoxazole) 2-3 oz 3-4 10

Pest Biology: Scouting/Threshold: Cultural: • mites become active in spring, • red and brown mites occur • prevent tree water stress and thrive in cool conditions; sporadically; look for small reddish or brown mites feed on leaves at brown dots on lower leaf surface or night and rest on twigs at day shake branch over paper

Conventional: Grasshoppers Dimilin 2L, Orthene Dimilin 2L (diflubenzuron) 2 oz 3-4 15 97: for non-crop areas Orthene 97R (acephate) 4 oz 3 1 only (borders, fence rows, Sevin 4F (carbaryl) 0.5-1.5 qt 2-3 1 roadsides, etc.)

Reduced Risk/Organic: Semaspore Bait: most O effective on nymphs. Do Semaspore Bait (Nosema locustae) 1 lb 3 --- not use if rain w/in 8 hours.

Sevin: use higher rate for mature grasshoppers or applications to dense foliage. Bait form available.

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 66 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) GRASSHOPPERS (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs in the soil, • treat nymphs in spring along roads, • for more information, see and hatch in spring; transition ditches, fences, and weedy areas; adults Chapter 2, Grasshoppers, pages from nymph to adult takes 5 are more difficult to treat 13-14 molts

Lygus and Stink Conventional: Asana XL: given rate is Apple bugs Asana XL (esfenvalerate) 4.8-14.5 oz 2 3 for concentrate spray, see Danitol 2.4 EC (fenpropathrin) 16-21.3 oz 4 3 label for dilute spray rate. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 WarriorR (lambda-cyhalothrin) 2.5-5 oz 4 3 Belay: label expires Oct. 2, 2012. Max 12 oz/season.

Reduced Risk/Organic: Beleaf: max 8.4 oz per Belay (clothianidin) 6-12 oz --- 4 season. Thorough spray Beleaf 50SG (flonicamid) 2-2.8 oz 4 9 coverage is essential.

Pest Biology: Scouting/Threshold: Cultural: • migrate to nearby fruit trees • look for adults in weeds and borders • do not mow nearby weeds or when host field crops are with sweep nets cover crops when fruit is present harvested or weeds mowed

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 67 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) Conventional: Powdery Protect susceptible mildew Indar 2F (fenbuconazole) 6-8 oz 4 3 varieties: Gala, Idared, Inspire Super MP (difenoconazole) + Vangard 4 oz each 4 3/9 Jonagold, Jonathan, and WG (cyprodinil) Rome. McIntosh and Pristine (boscalid/pyraclostrobin) 14.5-18.5 oz 4 7/11 Golden and Red Delicious Procure 50WS (triflumizole) 8-16 oz 4 3 are mildly affected. Rally 40WSP (myclobutanil) 5-10 oz 4 3 Biologicals (Serenade, Rubigan E.C. (fenarimol) 8-12 oz 4 3 etc.) and oils (Trilogy, Sovran (kresoxim-methyl) 4.0-6.4 oz 3 11 Sporan) must be applied Sulforix (calcium polysulfide/lime sulfur) 2 qt/100 g 3 M2 before infection; they act as a protectant. Apple Topsin M 70 WDG (thiophanate-methyl) 1.0-1.5 lb 2-3 1

Sovran: 25.6 oz/acre Reduced Risk/Organic: max per season. Flint (trifloxystrobin) 2.0-2.5 oz 3-4 11 KaligreenO, MilStopO (potassium bicarbonate) See label 3 NC Sulfur: must be reapplied lime-sulfurO See label 3 M2 every 7-10 days and may burn leaves, especially RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC when temps. >90° F. Serenade ASOO (Bacillus subtilis strain QST 713) 2-6 qt 2 NC Serenade MAXO (Bacillus subtilis strain QST 713) 1-3 lb 2 NC SonataO (Bacillus pumilis strain QST 2808) 2-4 qt 2 NC SporanO (rosemary, clove, and thyme oils) 0.5-1 qt/25 g 2 NC Stylet-Oil (paraffinic oil) See label 4 NC 80% ThiosperseO (sulfur) 30 lb 2 M2 TrilogyO (extract of neem oil) See label 2 NC

Pest Biology: Scouting/Threshold: Cultural: • infections may continue • maintain protection if new infections • none through the summer in humid continue conditions

Conventional: San Jose scale Apply 1-2 applications R Diazinon 50W (diazinon) See label 3 1 during crawler stage. Imidan 70-W (phosmet) 3.5-5.33 lb 1 1 Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 2 3/4 Centaur WDG: limited to one application/year on apples. Reduced Risk/Organic: O Aza-Direct , Azatin XL, Ecozin Plus 1.2% See label 1 UN Diazinon 50W: max is O O ME , Neemix 4.5 (azadirachtin) two applications/season. Centaur WDG (buprofezin) 34.5 oz 4 16 Esteem 35 WP (pyriproxyfen) + hort. oil See label 3-4 7 Tourismo: do not apply more than 3 times per crop season.

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 68 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apple

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) SAN JOSE SCALE (continued) Pest Biology: Scouting/Threshold: Cultural: • the immature crawler stage • place double-sided tape around • none is active in late spring/early infested limbs and monitor for activity summer of crawlers across tape

Conventional: Spider mites Agri-Flex: apply before Agri-FlexR (abamectin/thiamethoxam/) 5.5-8.5 oz 4 4/6

a threshold of 5 spider Apple Envidor 2 SC (spirodiclofen) 16-18 oz 4 23 mites per leaf is reached. Kelthane 50WSP (dicofol) See label 3 UN Using with oil can russet Nexter (pyridaben) 8.8-10.7 oz 2-3 21 light-skinned varieties such Onager (hexythiazox) 12-24 oz 4 10 as Golden Delicious. Savey 50 DF (hexythiazox) 3-6 oz 4 10 Nexter: only one application is allowed per Reduced Risk/Organic: season. Acramite-50WS (bifenazate) 0.75-1 lb 4 UN Portal: do not apply BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC more than 2 pints per acre FujiMite 5EC (fenpyroximate) 2 pints/100 g 4 21 each season. Kanemite 15 SC (acequinocyl) 21-31 oz 3 20 M-PedeO (potassium salts of fatty acids) See label 2-3 NC Zeal: predominately Portal (fenpyroximate) 2 pints 4 21 an ovicide/larvicide and should be used early in VegolO (canola oil) See label 2-3 NC the life cycle of mites. Has Zeal (etoxazole) 2-3 oz 3-4 10 translaminar activity.

Pest Biology: Scouting/Threshold: Cultural: • most likely to become a • look for “burning” or russeting of • predatory mites commonly problem during hot, dry leaves and small mites on undersides suppress spider mites, so avoid conditions in July to September of lowest, interior leaves first; treat insecticide unless necessary, when mites reproduce rapidly only if “leaf burn” is evident especially pyrethroids in spring

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 69 Apple Chapter 6: Spray Tables

APPLE Pest Management Recommendations Rate M (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) Conventional: White apple Admire Pro: max is 14 leafhopper Admire Pro (imidacloprid) - foliar application 1.4-2.8 oz 4 4 oz/acre per season for Calypso 4 F (thiacloprid) 2-4 oz 4 4 foliar application. Clutch 50 WDG (clothianidin) 2-3 oz 4 4 Danitol 2.4 EC (fenpropathrin) 10.3-21.3 oz 3 3 Centaur WDG: limited Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 to one application/year. thiamethoxam/chlorantraniliprole Voliam Flexi ( ) 4-7 oz 4 3/28 Surround WP: apply within 3 days of first petal Reduced Risk/Organic: fall or at initial infestation. Assail 30 SG (acetamiprid) 2.5-4.0 oz 3 4 Tourismo: do not apply Apple Avaunt (indoxacarb) 5-6 oz 3-4 22 more than 3 times per Aza-DirectO, Azatin XL,Neemix 4.5O See label 1 UN crop season (azadirachtin) Centaur WDG (buprofezin) 9-12 oz 3 16 Voliam Flexi: toxic to M-PedeO (potassium salts of fatty acids) See label 2-3 NC bees. Surround WPO (kaolin clay) See label 1 NC VegolO (canola oil) See label 2 NC

Pest Biology: Scouting/Threshold: Cultural: • best to manage nymphs early • monitor with beating tray; if • none in season, as adults are difficult population exceeds one nymph per to control; a second generation terminal, treat before older nymphs occurs in July-Aug (with long wing pads) are present

Conventional: Woolly apple Assail 30 SG: repeat R aphid Diazinon 50W (diazinon) 1 lb/100 gal 4 1 applications may be Thionex 50WR (endosulfan) 4 lb 4 2 required for woolly apple aphid control. Reduced Risk/Organic: Assail 30 SG (acetamiprid) 2.5-4.0 oz 2-3 4 Diazinon, Thionex: highly toxic to bees. Do Beleaf 50SG (flonicamid) 2-2.8 oz 2-3 9 not apply Diazinon more O horticultural oil See label 2-3 NC than two times per year. M-PedeO (potassium salts of fatty acids) See label 2-3 NC Do not apply Thionex SucraShieldO (sucrose octanoate esters) See label --- NC more than three times per year. VegolO (canola oil) See label 2 NC

Pest Biology: Scouting/Threshold: Cultural: • colonies start forming on • look for white cottony colonies in • many beneficial insects help suckers or low in the tree by bark cracks and crevices and suckers suppress aphids, so avoid June insecticides unless necessary

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 70 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Pear

PEAR Pest Phenology Calendar Stages of Development

Post Bloom / Summer Major Buds Tight First Full Petal Post Dormant White Exposed Cluster Bloom Bloom Fall Harvest Pests June July August Sept.

Codling Immatures on Larvae under bark Pupae under bark Adults, eggs, larvae in fruit Moth limbs

Fire Blight Overwinters in cankers Multiple sprays during bloom may be necessary when weather is favorable

Iron Early spring soil treatments most effective; Difficult to control with foliar summer sprays Chlorosis

Pear

Use decline-resistant rootstocks. Remove diseased trees Pear Decline

Adults on limbs, egg-laying Winter Pear Psylla Nymphs, Summer adults / Eggs on leaves and fruit begins in March adults

Pear Slug Pupae in soil Adults, eggs, larvae on leaves Pupae in soil

Rust Mite Adults under and Blister Eggs, immatures, adults in buds, on leaves & fruit Eggs on limbs buds Mite San Jose Adults, crawlers, immatures on Immatures on Immatures on limbs Scale limbs, leaves, & fruit limbs

Spider Adults at base of Eggs, Immatures, adults on ground cover and tree leaves Adults Mites tree

Zinc Dormant sprays most effective; Foliar sprays only marginally effective Deficiency

Utah-Colorado Tree Fruit Production Guide 71 Pear Chapter 6: Spray Tables

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments DORMANT Reduced Risk/Organic: Fire blight Using copper after delayed C-O-C-S WDG (copper oxychloride) 2-4 lb 2 M1 dormant stage may cause Cuprofix Ultra 40 (copper sulfate) 7.5-10 lb 2 M1 russeting. Copper may Nordox 75 WGO (cuprous oxide) 0.6-1.25 lb 2 M1 reduce inoculum, but antibiotics must be used during bloom.

Pest Biology: Scouting/Threshold: Cultural: • overwinters in cankers in the • spray trees just before bud break • during dry weather, prune orchard; cankers start to ooze dormant limbs infected with bacteria when temperatures cankers 12” below visible warm canker margins

Pear horticultural oil + one of the following: See label 2 NC Pear psylla Asana XL: given rate is for concentrate spray, see label Conventional: for dilute spray rate. Ambush 25WR (permethrin) 12.8-25.6 oz 3 3 Asana XLR (esfenvalerate) 4.8-14.5 oz 3 3 Bugitol: apply 96 oz/100 Calypso 4 F (thiacloprid) 4-8 oz 4 4 gal per acre for heavy infestations. Pounce 3.2 ECR (permethrin) 8-16 oz 3 3 ProaxisR (gamma-cyhalothrin) 2.5-5 oz 3 3 Delegate WG: do not apply Thionex 3EC (endosulfan) 3 1/3 qt 4 2 more than a total of 29 oz WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 3 per acre per crop. Control of pear psylla may be improved by addition of an adjuvant to Reduced Risk/Organic: the spray mixture. Assail 70WP (acetamiprid) 1.7-3.4 oz 4 4 Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC Delegate WG (spinetoram) 6-7 oz 4 5 Esteem 35 WP (pyriproxyfen) 4-5 oz 3-4 7 lime sulfurO See label 3 M2 Neemix 4.5O (azadirachtin) 7-16 oz 2 UN SucraShieldO (sucrose octanoate esters) See label --- NC Surround WPO (kaolin clay) See label 3-4 NC VegolO (canola oil) See label 2-3 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as adults outside • treat if adults are detected in spring • can be active over a long time the orchard and fly into pear period, so one spray may not trees about 6 weeks before be adequate bloom (March) to lay eggs

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 72 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Pear

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments DELAYED DORMANT (Swollen Bud to Tight Cluster) European Reduced Risk/Organic: red mite and Golden pest spray oilO (soybean oil) 4-6 gal 3 NC Brown mite horticultural oilO See label 4 NC eggs

(these pests rarely need treatment in Colorado or Utah) Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs on limbs; • look for red eggs on limbs • none take advantage of their exposure at this time Pear

Pearleaf blister Conventional: mite and Rust Sevin 4F (carbaryl) 1.5-3 qt 3 1 mites Reduced Risk/Organic: (these pests rarely BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC need treatment) Golden Pest Spray Oil O (soybean oil) 4-6 gal 3 NC horticultural oilO See label 4 NC 80% ThiosperseO (sulfur) 30 lb 3 M2 VegolO (canola oil) See label 3 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as adults under bud • treat if damage is severe the prior season; • none scales and migrate to leaves at bud break is optimal treatment timing bud break

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 73 Pear Chapter 6: Spray Tables

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments DELAYED DORMANT (Swollen Bud to Tight Cluster) (continued) horticultural oil + one of the following: See label 2 NC Pear psylla Allityn: only an insect repellant; not labeled to kill. Conventional: Ambush 25WR (permethrin) 12.8-25.6 oz 3 3 Asana XL: given rate is for Asana XLR (esfenvalerate) 4.8-14.5 oz 3 3 concentrate spray, see label Calypso 4 F (thiacloprid) 4-8 oz 4 4 for dilute spray rate. R Dimilin 2L (diflubenzuron) 40-48 oz 3 15 Bugitol: apply 96 oz/100 Pounce 3.2 ECR (permethrin) 8-16 oz 3 3 gal per acre for heavy ProaxisR (gamma-cyhalothrin) 2.5-5 oz 3 3 infestations. Thionex 3EC (endosulfan) 3 1/3 qt 4 2 : max 2 R 2.5-5 oz 3 3 Centaur Warrior (lambda-cyhalothrin) applications/season.

Reduced Risk/Organic: Delegate WG: do not apply Pear Allityn (garlic juice extracts) See label --- NC more than a total of 29 oz Assail 70WP (acetamiprid) 1.7-3.4 oz 4 4 per acre per crop. Control of O pear psylla may be improved Aza-Direct , Azatin XL (azadirachtin) See label 2 UN by addition of an adjuvant to Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC the spray mixture. Centaur WDG (buprofezin) 34.5-46 oz 2-3 16 Delegate WG (spinetoram) 6-7 oz 4 5 Dimilin 2L: a horticultural Esteem 35 WP (pyriproxyfen) 4-5 oz 3-4 7 oil should also be used at a rate of 4-6 gallons per acre. O See label 3 M2 lime sulfur Make application during egg O Neemix 4.5 (azadirachtin) 7-16 oz 2 UN deposition so that it will SucraShieldO (sucrose octanoate esters) See label --- NC come in contact with pear Surround WPO (kaolin clay) See label 3-4 NC psylla eggs and nymphs. VegolO (canola oil) See label 2-3 NC

Pest Biology: Scouting/Threshold: Cultural: • egg-laying continues at this • treat at this time if dormant spray was • none time missed, or if population is large

Reduced Risk/Organic: Soft scale Oil is the best option at this Esteem 35 WP (pyriproxyfen) 4-5 oz 4 7 timing. (this pest is horticultural oilO 2% 4 NC rarely a problem VegolO (canola oil) See label 3 NC in commercial orchards)

Pest Biology: Scouting/Threshold: Cultural: • overwinter as immatures on • look for small, circular, brown shapes on • scrape overwintering bodies limbs; crawlers hatch in early twigs off with stiff brush summer

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 74 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Pear

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments PRE-BLOOM (White Bud - Full White) Conventional: Powdery Sonata/Serenade: best mildew Inspire Super MP (difenoconazole) + 4 oz each 3 3/9 when used early or when Vangard WG (cyprodinil) disease pressure is low. Apply Pristine (boscalid/pyraclostrobin) 14.5-18.5 oz 4 7/11 twice at 7-10 day interval; Procure 50WS (triflumizole) 8-16 oz 4 3 switch to a stronger product Sovran (kresoxim-methyl) 4.0-6.4 oz 3 11 after first two treatments. Topsin M 70 WDG (thiophanate-methyl) 1 lb 3 1 Sovran: 25.6 oz/acre max per season. Reduced Risk/Organic: Flint (trifloxystrobin) 2.0-2.5 oz 4 11 KaligreenO, MilStopO (potassium bicarbonate) See label 3 NC O Bacillus subtilis strain QST 713 1-3 lb 2 NC

Serenade MAX ( ) Pear SonataO (Bacillus pumilus strain QST 2808) 2-4 qt 2 NC SporanO (rosemary, clove, and thyme oils) 0.5-1 qt/25 g --- NC 80% ThiosperseO (sulfur) 30 lb 3 M2 TrilogyO (clarified extract of neem oil) See label 1-2 NC

Pest Biology: Scouting/Threshold: Cultural: • fungus overwinters in and on • watch terminals at open cluster stage for • some cultivars are more terminal buds new infections resistant

BLOOM Reduced Risk/Organic Codling moth Install mating disruption Checkmate CM-O Puffer (Suterra) 1-2 --- NC just before first moth flight Checkmate CM-XL (Suterra) 200 2-3 NC (biofix), around full bloom of Cidetrak CM (Trece) 400 4 NC Red Delicious. Isomate-CM Flex (Pacific BioControl) 200-400 4 NC Isomate-C plus (Pacific BioControl) 200 4 NC Supplemental insecticides may be necessary; monitoring with traps is critical. See page 12- 13 for more information.

Pest Biology: Scouting/Threshold: Cultural: • moths start emerging from • after mating disruption is hung, install • none pupation around first bloom monitoring traps using Trece CM- of Red Delicious, mate, and lay DA Combo lure; trap threshold for eggs on leaves and fruit treatment is 10 moths (cumulative capture)

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 75 Pear Chapter 6: Spray Tables

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments BLOOM (continued) Conventional: Fire blight Biologicals: work best in Agri-Mycin17 (streptomycin) 24-48 oz 3-4 25 a program with antibiotics; Mycoshield, FlameOut (oxytetracycline) See label 2-3 41 apply early bloom as it must be present before risk of Reduced Risk/Organic: infection; wait 1-2 days BlightBanO A506 (Pseudomonas fluorescens See label 2 NC before applying antibiotic. A506) Copper (for example O FireLine 17WP (oxytetracycline) See label 2-3 41 Nordox) may cause fruit Nordox 75 WGO (cuprous oxide) 0.6-1.25 lb 2 M1 russeting. RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC Serenade MAXO (Bacillus subtilis strain QST 2-3 lb 2 NC 713)

Pear Pest Biology: Scouting/Threshold: Cultural: • when rain occurs and average • look for oozing cankers in early spring • none temperatures >60° F, bacteria • repeat every 5 days during bloom when may be spread to open flowers CougarBlight model predicts infection

PETAL FALL Conventional: Crown and Aliette WDG: max 5.0 lb/ root rot Aliette WDG (aluminum tris) 2.5-5 lb 2 33 acre/application, and 20 lb per (Phytophthora) season. Reduced Risk/Organic: (this disease is Agri-Fos (mono- and dibasic sodium, 0.5-1 tsp/1 g 2 33 Fosphite and Agri-Fos: rarely a problem potassium, and ammonium phosphites) repeat 2-4 times until control on pears) Fosphite (salts of phosphorous acid) 1-3 qt/100 g 2 33 is reached. Protects healthy trees growing next to Phytophthora-killed trees.

Pest Biology: Scouting/Threshold: Cultural: • Phytophthora causes root • watch for trees that are slow to leaf out, • remove dead/dying tree(s) and rot and crown rot (death have slow growth, or die back do not replant in the same site of cambium) in wet, poorly without improving drainage drained conditions • avoid excessive irrigation

Conventional: Lygus and Stink Belay: label expires Oct. 2, bugs Danitol 2.4 EC (fenpropathrin) 16-21.33 oz 4 3 2012. Max 12 oz/season. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 Thionex 50WR (endosulfan) 4 lb 2-3 2 Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 3/28 chlorantraniliprole)

Reduced Risk/Organic: Belay (clothianidin) 6-12 oz --- 4

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 76 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Pear

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments PETAL FALL (continued)

LYGUS AND STINK BUGS (continued) Pest Biology: Scouting/Threshold: Cultural: • often overwinter in alfalfa or • use a sweep net in neighboring fields or • remove weed host plants other field crops and migrate weedy edges prior to fruit forming on trees to nearby fruit trees when • do not mow nearby weeds crops are harvested; cause cat- or cover crops when fruit is facing injury to fruit present or the insects will move to fruit trees

Conventional: Leafrollers Agree WG, Javelin WG, Belt SC (flubendiamide) 3-5 oz 4 28 (European, Deliver: most effective when Pear fruittree, and Imidan 70-W (phosmet) 3.5-7 lb 1 1 larvae are less than 1/2 inch obliquebanded) Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 in size. Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 do not make more (these pests rarely Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 3/28 Altacor: than 4 applications per season need treatment in chlorantraniliprole) Colorado or Utah) and do not apply more than 9 oz per crop per acre per year. Reduced Risk/Organic: Agree WGO (Bacillus thuringiensis sub. 1-2 lb 3-4 11 Bugitol: apply 96 oz/100 aizawai strain GC-91) gal per acre for heavy Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 infestations. O Aza-Direct , Azatin XL (azadirachtin) See label 2 UN Delegate WG: do not make Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC more than 4 applications per Delegate WG (spinetoram) 4.5-7.0 oz 4 5 calendar year. Do not apply DeliverO (Bacillus thuringiensis sub. kurstaki 0.5-2.0 lb 3-4 11 more than a total of 29 oz strain SA-12) per acre per crop. O Entrust (spinosad) 2-3 oz 4 5 Entrust: do not apply more Garlic Barrier AG+O (garlic juice) See label 2 NC than a total of 9 oz per acre Intrepid 2F (methoxyfenozide) 8-16 oz 3-4 18 per crop. Javelin WGO (Bacillus thuringiensis sub. 0.5-4 lb 3-4 11 kurstaki strain SA-11) Garlic Barrier AG+: insect repellent. Neemix 4.5O (azadirachtin) 7-16 oz 2 UN Success (spinosad) 6-10 oz 4 5 Success: do not apply more SucraShieldO (sucrose octanoate esters) See label --- 5 than a total of 29 oz per acre per crop. Pest Biology: Scouting/Threshold: Cultural: • fruittree leafrollers overwinter • check fruit spurs for honeycomb egg • treatments for codling moth as eggs; obliquebanded masses and/or larvae; use beating tray to will also control leafrollers leafrollers overwinter as sample for larvae immatures in protected sites • if using mating disruption for codling moth, leafroller damage may increase due to reduced sprays, so monitoring may be necessary

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 77 Pear Chapter 6: Spray Tables

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments PETAL FALL (continued) Conventional: Pear psylla Admire Pro: do not apply Admire Pro (imidacloprid) - foliar 7 oz 3-4 4 more than 14 oz/acre per Agri-Mek 0.15ECR (abamectin) + 2% 10-20 oz 3-4 6 season for foliar applications horticultural oil Calypso 4 F (thiacloprid) 4-8 oz 3-4 4 Agri-Mek 0.15EC: given Clutch 50 WDG (clothianidin) 4-6 oz 3-4 4 rate is for concentrate spray, see label for dilute spray rate. Nexter (pyridaben) 6.6-10.7 oz 3-4 21 Voliam Flexi (thiamethoxam/chlorantraniliprole) 7 oz 3 4/28 Allityn: only an insect repellant; not labeled to kill. Reduced Risk/Organic: Actara (thiamethoxam) 5.5 oz 3-4 4 Assail 70WP: use with oil. Allityn (garlic juice extracts) See label --- NC Bugitol: apply 96 oz/100 Assail 70WP (acetamiprid) 1.7-3.4 oz 3-4 4 gal per acre for heavy Pear Aza-DirectO (azadirachtin) 1-2 pints 2 UN infestations. Azatin XL, Neemix 4.5O (azadirachtin) See label 2 UN Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC Delegate WG: max 29 oz per acre per crop. Use with Delegate 25 WG (spinetoram) 6-7 oz 4 5 adjuvant to improve control. Esteem 35 WP (pyriproxyfen) 4-5 oz 3 7 FujiMite 5EC (fenpyroximate) 2 pints 4 21 Esteem 35 WP: use with Garlic Barrier AG+O (garlic juice) See label --- NC oil. M-PedeO (potassium salts of fatty acids) See label 3 NC Garlic Barrier AG+: insect O See label 2-3 NC Vegol (canola oil) repellent.

Nexter: only one application is allowed per season. Pest Biology: Scouting/Threshold: Cultural: • eggs hatch during bloom and • only treat in lieu of the dormant or • none nymphs move to foliage delayed-dormant spray, if adults are still • feeding results in sticky active at petal fall, or if psylla injury was honeydew, leaf burn, and fruit severe in the previous year russeting

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 78 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Pear

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments PETAL FALL (continued) Conventional: Powdery 80% Thiosperse: do not mildew Inspire Super MP (difenoconazole) + 4 oz each 3 3/9 apply after fruit begins to turn Vangard WG (cyprodinil) down. Pristine (boscalid/pyraclostrobin) 14.5-18.5 oz 4 7/11 Rubigan E.C. (fenarimol) 8-12 oz 4 3 Topsin M 70 WDG (thiophanate-methyl) 1 lb 3 1

Reduced Risk/Organic: Armicarb, KaligreenO, MilStopO (potassium See label 2 NC bicarbonate) Flint (trifloxystrobin) 2.0-2.5 oz 4 11 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC Pear SporanO (rosemary, clove, thyme oil) .5-1 qt/25 g --- NC 80% ThiosperseO (sulfur) 30 lb 3 M2 TrilogyO (clarified extract of neem oil) See label 2 NC

Pest Biology: Scouting/Threshold: Cultural: • more prevalent in wet • look for new infections on leaves • avoid hitting leaves with conditions irrigation water

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 79 Pear Chapter 6: Spray Tables

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments FRUIT PRESENT Conventional: Codling moth Altacor: ovicide plus Belt SC (flubendiamide) 5 oz 3 28 larvicide; do not make more Calypso 4 F (thiacloprid) 4-8 oz 3-4 4 than 4 applications per season Endigo ZCR (thiamethoxam/lambda-cyhalothrin) 5-6 oz 2-3 3/4 and do not apply more than 9 Imidan 70-W (phosmet) 3.5-7 lb 3-4 1 oz/acre per year. Intrepid 2F (methoxyfenozide) 16 oz 3 18 R Assail 70WP: adding Leverage 360 (cyfluthrin/imidacloprid) 2.4-2.8 oz 3-4 3/4 horticultural oil may enhance Tourismo (buprofezin/flubendiamide) 15-17 oz 4 16/28 control. Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 4 3/28 Delegate WG: ovicide chlorantraniliprole) plus larvicide; do not make more than 4 applications per year. Do not apply more than Reduced Risk/Organic: a total of 29 oz/acre per year. Pear Agree WGO (Bacillus thuringiensis sub. 1-2 lb 2 11 aizawai strain GC-91 Entrust: max is 9 oz/acre Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 per year. Assail 70WP (acetamiprid) 1.7-3.4 oz 3-4 4 Esteem 35 WP: ovicide; O O Carpovirusine , CYD-X , Virosoft (Cydia See label 3-4 NC combine with a horticultural pomonella granulosis virus) oil for best results. Lasts 14 Delegate WG (spinetoram) 6-7 oz 4 5 days. DeliverO (Bacillus thuringiensis sub. kurstaki 0.5-2.0 lb 2 11 strain SA-12) Tourismo: do not apply O more than 3 times per crop Entrust , Success (spinosad) See label 2-3 5 season. Esteem 35 WP (pyriproxyfen) 4-5 oz 3 7 Javelin WGO (Bacillus thuringiensis sub. 0.5-4 lb 2 11 kurstaki strain SA-11)

Pest Biology: Scouting/Threshold: Cultural: • larvae hatch from eggs laid on • start treatment 10 days after petal fall or • trunk banding & fruit bagging and near fruits 220 degree-days after first adult moth • remove fruit bins and other activity structures from orchards where larvae can overwinter

Conventional: Lygus and Stink Belay: label expires Oct. 2, bugs Danitol 2.4 EC (fenpropathrin) 16-21.3 oz 4 3 2012. Max 12 oz/season. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3 3/4 Thionex 50WR (endosulfan) 4 lb 2-3 2 Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 3/28 chlorantraniliprole)

Reduced Risk/Organic: Belay (clothianidin) 6-12 oz --- 4

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 80 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Pear

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) LYGUS AND STINK BUGS (continued) Pest Biology: Scouting/Threshold: Cultural: • these bugs migrate to nearby • use a sweep net in neighboring fields or • do not mow nearby weeds fruit trees when crops are weedy edges or cover crops when fruit is harvested present or the insects will move to fruit trees

Conventional: Pear sawfly Altacor: do not apply more R (Pear or Cherry Leverage 360 (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 than 9 oz per crop per acre slug) Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 4 3/28 per year. chlorantraniliprole)

(this pest rarely Bugitol: apply 96 oz/100 Pear needs treatment gal per acre for heavy Reduced Risk/Organic: in commercial infestations. orchards) Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN Garlic Barrier AG+: insect Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC repellent. Garlic Barrier AG+O (garlic juice) See label --- NC

Pest Biology: Scouting/Threshold: Cultural: • larvae feeds on the upper leaf • trees can tolerate low populations • none surface causing skeletonizing in mid to late summer

Conventional: Powdery 80% Thiosperse: do not mildew Inspire Super MP (difenoconazole) + 4 oz each 3 3/9 apply after fruit begins to turn Vangard WG (cyprodinil) down. Pristine (boscalid/pyraclostrobin) 14.5-18.5 oz 4 7/11 Rubigan E.C. (fenarimol) 8-12 oz 4 3 Topsin M 70 WDG (thiophanate-methyl) 1 lb 3 1

Reduced Risk/Organic: Armicarb, KaligreenO, MilStopO (potassium See label 2 NC bicarbonate) Flint (trifloxystrobin) 2.0-2.5 oz 4 11 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC SporanO (rosemary, clove, thyme oil) .5-1 qt/25 g --- NC 80% ThiosperseO (sulfur) 30 lb 3 M2 TrilogyO (clarified extract of neem oil) See label 2 NC

Pest Biology: Scouting/Threshold: Cultural: • more prevalent in wet • look for new infections on leaves • avoid hitting leaves with conditions irrigation water

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 81 Pear Chapter 6: Spray Tables

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments FRUIT PRESENT (continued) Conventional: Spider mites Agri-Mek 0.15EC: given R Agri-Flex (abamectin/thiamethoxam) 5.5-8.5 oz 4 4/6 rate is for concentrate spray, Agri-Mek 0.15ECR (abamectin) + 2% 10-20 oz 3-4 6 see label for dilute spray rate. horticultural oilO Apollo SCR (clofentezine) 4-8 oz 2-4 10 Nexter: only one application is allowed per season. Envidor 2 SC (spirodiclofen) 16-18 oz 3-4 23 Kelthane 50WSP (dicofol) See label 1-3 UN Vendex 50WP: do not mix Nexter (pyridaben) 8.8-10.7 oz 2-3 21 with more than 400 gallons of Onager (hexythiazox) 12-24 oz 3 10 water per acre. Savey 50 DF (hexythiazox) 3-6 oz 2-4 10 Vendex 50WPR (fenbutatin-oxide) 1-2 lb 3 12 Zeal: predominately an ovicide/larvicide and should be used early in the life cycle Reduced Risk/Organic: of mites. Pear Acramite-50WS (bifenazate) 0.75-1 lb 4 UN BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC FujiMite 5EC (fenpyroximate) 2 pints/100 g 3 21 Kanemite 15 SC (acequinocyl) 21-31 oz 4 20 M-PedeO (potassium salts of fatty acids) See label 1-2 NC SucraShieldO (sucrose octanoate esters) See label --- NC VegolO (canola oil) See label 3 NC Zeal (etoxazole) 2-3 oz 3-4 10

Pest Biology: Scouting/Threshold: Cultural: • most likely to become a • pears are highly sensitive to “mite burn.” • predatory mites commonly problem during hot, dry Leaves turn dark brown to black quickly. suppress spider mites, so avoid conditions in late summer Look for small mites in late June on insecticides unless necessary when mites reproduce rapidly undersides of leaves, starting with lowest, interior leaves first

POST-HARVEST Conventional: Pearleaf blister Agri-Mek 0.15EC: given R mite and Rust Agri-Mek 0.15EC (abamectin) 10-20 oz 4 6 rate is for concentrate spray, mites Kelthane 50WSP (dicofol) See label 4 UN see label for dilute spray rate. Sevin 4F (carbaryl) 1.5-3 qt 3 1 (these pests rarely need treatment Reduced Risk/Organic: in commercial O See label --- NC orchards) Biomite (Citronellol, Farnesol, Geraniol, Nerolidol) flowable/micronized sulfurO See label 3 M2 lime-sulfur + horticultural oilO See label 4 M2 M-PedeO (potassium salts of fatty acids) See label 1-2 NC SucraShieldO (sucrose octanoate esters) See label --- NC 80% ThiosperseO (sulfur) 30 lb 3 M2 VegolO (canola oil) See label 3 NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 82 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Pear

PEAR Pest Management Recommendations M Rate (per O Pest Products acre) Eff. A Comments POST-HARVEST (continued) LEAF BLISTER MITE AND RUST MITES (continued) Pest Biology: Scouting/Threshold: Cultural: • blister mites live in blisters on • look for russeting of fruit and leaves • none leaves throughout the summer • treat before leaves drop and mites move • adults move to bud scales to to buds to spend the winter overwinter

Conventional: Pear psylla Asana XL: given rate is for R Asana XL (esfenvalerate) 4.8-14.5 oz 3 3 concentrate spray, see label Calypso 4 F (thiacloprid) 4-8 oz 4 4 for dilute spray rate. ProaxisR (gamma-cyhalothrin) 2.5-5 oz 3 3 Pear Thionex 3EC (endosulfan) 3.3 qt 4 2 Centaur: max 2 applications/season. WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 3 Delegate WG: do not apply Reduced Risk/Organic: more than a total of 29 oz Assail 70WP (acetamiprid) 1.7-3.4 oz 4 4 per acre per crop. Control of Centaur WDG (buprofezin) 34.5-46 oz 2-3 16 pear psylla may be improved by addition of an adjuvant to 5 Delegate WG (spinetoram) 6-7 oz 4 the spray mixture. Esteem 35 WP (pyriproxyfen) 4-5 oz 3-4 7 lime sulfurO See label 3 M2 Esteem 35 WP: apply with an oil spray at the manufacturers recommended rate.

Pest Biology: Scouting/Threshold: Cultural: • continue feeding on leaves until • treat only if a problem • none fall and then migrate out of orchard

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 83 Cherry (Tart and Sweet) Chapter 6: Spray Tables

CHERRY Pest Phenology Calendar Stages of Development Green Tight Open First Full Petal Post Bloom / Summer Post Major Pests Dormant Tip Cluster Cluster Bloom Bloom Fall June July Aug. Sept. Harvest Black Cherry Nymphs / winged and wingless adults on Eggs on limbs Eggs on limbs Aphid new growth- move to non-fruit hosts

Cherry Powdery Fungus overwinters as Conidia spread to new leaves Mildew spores on tree surface

Cherry (Pear) Pupae in soil Adults, eggs, larvae on leaves Pupae in soil Slug

Iron Chlorosis Apply to soil prior to leaf emergence; Repeat foliar applications on new growth

Leucostoma Conidia are spread in splashing rain; Winter damaged trees are susceptible (Cytospora) Phytophthora Cherry Root & Collar Zoospores active during entire season when water is present Rot Adults, crawlers, immatures Immatures on San Jose Scale Immatures on limbs on limbs, leaves, & fruit limbs

Adults, eggs, larvae Shothole Borer Larvae underneath bark Larvae underneath bark underneath bark

Adults at base of Adults at Spider Mites Eggs, immatures, adults on ground cover and tree leaves tree base of tree

Western Cherry Adults, eggs, larvae Pupae in soil Pupae in soil Fruit Fly in fruit

84 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Cherry (Tart and Sweet)

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A DORMANT Bacterial canker Conventional: Apply copper as a dormant Champ Dry Prill, Champ Formula 2, Kocide See label 2 M1 application before foliage 101 (copper hydroxide) buds swell.

Reduced Risk/Organic: Nordox 75 WGO (cuprous oxide) 5-13 lb 2 M1

Pest Biology: Scouting/Threshold: Cultural: • cankers start to ooze in spring • none • prune out cankers before warm weather

Shothole Conventional: Champ Dry Prill: make (Coryneum blight) Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 application before bud swell. Champ Dry Prill, Champ Formula 2, Kocide See label 3 M1 (this disease rarely 3000 (copper hydroxide) occurs on cherry in Cherry Colorado or Utah) Reduced Risk/Organic: Nordox 75 WGO (cuprous oxide) 5-13 lb 2-4 M1

Pest Biology: Scouting/Threshold: Cultural: • the fungus overwinters in • look for dead, oozing buds • prune out infected twigs cankers that ooze in spring

DELAYED DORMANT (Bud Swell - First White) Aphid eggs Conventional: Diazinon 50W: max is (Black cherry Assail 30 SG (acetamiprid) 2.5-5.3 oz 4 4 two applications/season. aphid) Diazinon 50WR (diazinon) See label 4 1 alone is effective. Thionex 50WR (endosulfan) 4-5 lb 2 2 Oil (sweet cherry only) Reduced Risk/Organic: Beleaf 50 SG (flonicamid) 2-2.8 oz 3 9 horticultural oilO See label 4 NC VegolO (canola oil) See label 4 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs on limbs • look for black eggs on limbs • none

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 85 Cherry (Tart and Sweet) Chapter 6: Spray Tables

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A DELAYED DORMANT (Bud Swell - First White) (continued) Lecanium scale Conventional: Centaur: max 2 Centaur WDG (buprofezin) 34.5-46 oz 4 16 applications/season. (this pest rarely needs treatment Reduced Risk/Organic: in commercial Golden Pest Spray OilO (soybean oil) 4-6 gal 3 NC orchards in Colorado O or Utah) horticultural oil See label 4 NC VegolO (canola oil) See label 4 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as nymphs on limbs; • none • none a soft scale

Shothole borer Conventional: Thionex: only products Sevin 4F (carbaryl) See label 2 1 with old label can be used Thionex 50W (endosulfan) See label 2 1 on tart cherry up to July 30, 2012. Cherry Pest Biology: Scouting/Threshold: Cultural: • adults fly from spring to mid • look for small (1/8 in. diameter) round • keep trees healthy with summer emergence holes in limbs and trunk adequate nutrition and • usually attack stressed trees irrigation

GREEN TIP TO TIGHT CLUSTER Shothole Conventional: Abound: start application (Coryneum blight) Rovral 4 F (iprodione) 1-2 pt 1 2 at the onset of disease as a protectant fungicide and (this disease rarely Reduced Risk/Organic: continue on a 7-14 day occurs on cherry in Abound (azoxystrobin) 12-15.5 oz 2-3 11 schedule. Colorado or Utah) O Nordox 75 WG (cuprous oxide) 5-13 lb 3 M1 Rovral 4 F: do not apply Pristine (pyraclostrobin/boscalid) 10.5-14.5 oz 4 7/11 after petal fall. RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC

Pest Biology: Scouting/Threshold: Cultural: • fungus causes holes in leaves and • none • prune out affected twigs scabs on cherry fruit

European red Conventional: Savey 50 DF: maximum of mite eggs Apollo SCR (clofentezine) 2-8 oz 4 10 one application per year. Onager, Savey 50 DF (hexythiazox) See label 4 10 (this pest rarely needs treatment in Reduced Risk/Organic: Colorado or Utah) horticultural oilO See label 4 NC VegolO (canola oil) See label 4 NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 86 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Cherry (Tart and Sweet)

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A GREEN TIP TO TIGHT CLUSTER (continued) EUROPEAN RED MITE EGGS (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs on limbs • look for red eggs on limbs • none

Lecanium scale Conventional: Centaur: max 2 Centaur WDG (buprofezin) 34.5-46 oz 4 16 applications/season. (this pest rarely needs treatment Reduced Risk/Organic: in commercial Golden Pest Spray OilO (soybean oil) 4-6 gal 3 NC orchards in Colorado O or Utah) horticultural oil See label 4 NC VegolO (canola oil) See label 4 NC

Pest Biology: Scouting/Threshold: Cultural:

• overwinter as nymphs on limbs; • none • none Cherry a soft scale San Jose scale Conventional: This treatment timing will Assail 30 SG (acetamiprid) 5.3-8.0 oz 3 4 kill overwintering nymphs Centaur WDG (buprofezin) 34.5-46 oz 4 16 but not overwintering Lorsban-4ER (chlorpyrifos) 1.5-4 pt 4 1 adults. In heavy infestations, apply second treatment targeting crawlers in early Reduced Risk/Organic: summer. Golden Pest Spray OilO (soybean oil) 4-6 gal 3 NC horticultural oilO See label 4 NC Centaur: max 2 applications/season. VegolO (canola oil) See label 3 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as nymphs on limbs; • look for gray-white scale bodies on limbs • none an armored scale

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 87 Cherry (Tart and Sweet) Chapter 6: Spray Tables

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A PETAL FALL Black cherry Conventional: Admire Pro: do not apply aphid Admire Pro (imidacloprid) - foliar application 1.4-2.8 oz 4 4 more than 10.5 oz/acre per Admire Pro (imidacloprid) - soil application 7-10.5 oz 4 4 season for soil application, (sweet cherry only) Assail 30 SG (acetamiprid) 2.5-5.3 oz 4 4 14 oz/acre per season for foliar application. Thionex 50WR (endosulfan) 4-5 lb 4 2 Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 Allityn: only an insect repellant; not labeled to kill. Reduced Risk/Organic: Actara (thiamethoxam) 3-4 oz 4 4 Bugitol: apply 96 oz/100 Allityn (garlic juice extract) See label --- NC gal per acre for heavy infestations. Aza-DirectO, Azatin XL (azadirachtin) See label 2-3 UN Beleaf 50 SG (flonicamid) 2-2.8 oz 4 9 Thionex 50W: can not be Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC used on cherries after July M-PedeO (potassium salts of fatty acids) See label 2-3 NC 31, 2012. VegolO (canola oil) See label 3 NC

Cherry Pest Biology: Scouting/Threshold: Cultural: • egg hatch begins at bud break; • if necessary, treat before substantial leaf curl • many beneficial insects aphid injury to new growth is occurs; insecticide penetration is diminished help suppress aphids; evident by petal fall after leaf curl avoid insecticides unless necessary

Conventional: Leafrollers Dipel: works best when (European, Belt SC (flubendiamide) 3-4 oz 4 28 applied to exposed larvae fruittree, and (1/2 inch in size or less). obliquebanded) Reduced Risk/Organic: Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Altacor: max is 4 (these pests rarely Delegate WG (spinetoram) 4.5-7 oz 4 5 applications/season (9 oz per crop per acre per need treatment in Dipel DFO (Bacillus thuringiensis sub. kurstaki) 0.5-2 lb 3 11 Colorado or Utah) year). EntrustO, Success (spinosad) See label 4 5 Intrepid 2F (methoxyfenozide) 8-16 oz 4 18

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs or immatures • look for rolled leaves with larvae inside • none on limbs; can feed on leaves and fruit, causing scarring

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 88 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Cherry (Tart and Sweet)

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A PETAL FALL (continued) Powdery mildew Conventional: Repeat throughout Adament 50 WG (tebuconazole/trifloxystrobin) 4-8 oz 3 3/11 emergence of new Elite 45 WP (tebuconazole) 4-8 oz 2 3 leaves. Sulfur may burn Gem 500 SC (trifloxystrobin) 1.9-3.8 oz 4 11 leaves, especially when temperatures >90° F. Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 Procure 50WS (triflumiziole) 8-16 oz 3-4 3 Abound: start application Quilt Xcel (propiconazole/azoxystrobin) 14 oz 3-4 3/11 at the onset of disease as Rally 40WSP (myclobutanil) 2.5-6.0 oz 3-4 3 a protectant fungicide and Rubigan E.C. (fenarimol) 6-12 oz 3 3 continue on a 7-14 day Tilt (propiconazole) 4 oz 3 3 schedule. Topsin M 70 WDG (thiophanate-methyl) See label 2-3 1 Procure 50WS: do not exceed 96 oz per acre per Reduced Risk/Organic: season. Abound (azoxystrobin) 12-15.5 oz 4 11 O O Rally 40WSP: do not

Armicarb, Kaligreen , MilStop (potassium See label 1 NC Cherry apply more than 3.25 lb per bicarbonate) acre per season. Cabrio EG (pyraclostrobin) 9.5 oz 3 11 Quash (metconazole) 3.5-4 oz 3 3 Rubigan E.C.: use a Quintec (quinoxyfen) 7 oz 3-4 13 surfactant when applied RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC alone. Serenade MAXO (Bacillus subtilis strain QST 713) 1-3 lb 1 NC Serenade, Sonata, and O Sonata (Bacillus pumilus strain QST 2808) 2-4 qt 2 NC botanical oils: work best SporanO (rosemary, clove, and thyme oils) .5-1 qt/25 g 1-2 NC early in the season. 80% ThiosperseO (sulfur) 4-30 lb 2 M2 TrilogyO (clarified extract of neem oil) See label 1-2 NC

Pest Biology: Scouting/Threshold: Cultural: • spore-producing structures • protect new leaves as needed overwinter on dead leaves and in cracks on the trunk; new infections begin in spring after rains/irrigation

Shothole Conventional: Abound: start application (Coryneum blight) Rovral 4 F (iprodione) 1-2 pt 1 2 at the onset of disease as a protectant fungicide and (this disease rarely Reduced Risk/Organic: continue on a 7-14 day occurs on cherry in Abound (azoxystrobin) 12-15.5 oz 2-3 11 schedule. Colorado or Utah) O Nordox 75 WG (cuprous oxide) 5-13 lb 3 M1 Rovral 4 F: do not apply Pristine (pyraclostrobin/boscalid) 10.5-14.5 oz 4 7/11 after petal fall. RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 89 Cherry (Tart and Sweet) Chapter 6: Spray Tables

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A PETAL FALL (continued) SHOTHOLE (Coryneum blight) (continued) Pest Biology: Scouting/Threshold: Cultural: • fungus causes holes in leaves and • none • prune out affected twigs scabs on cherry fruit

FRUIT PRESENT Black cherry Conventional: Admire Pro: do not apply aphid Admire Pro (imidacloprid) - foliar application 1.4-2.8 oz 4 4 more than 10.5 oz/acre per Admire Pro (imidacloprid) - soil application 7-10.5 oz 4 4 season for soil application, (sweet cherry only) Assail 30 SG (acetamiprid) 2.5-5.3 oz 4 4 14 oz/acre per season for foliar application. Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 R Thionex 50W (endosulfan) 4-5 lb 4 2 Allityn: only an insect Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 repellant; not labeled to kill. WarriorR (lambda-cyhalothrin) 2.5-5 oz 1 3 Bugitol: apply 96 oz/100 gal per acre for heavy Reduced Risk/Organic:

Cherry infestations. Actara (thiamethoxam) 3-4 oz 4 4 Allityn (garlic juice extract) See label --- NC Thionex 50W: can not be Aza-DirectO, Azatin XL (azadirachtin) See label 2-3 UN used on cherries after July Beleaf 50 SG (flonicamid) 2-2.8 oz 4 9 31, 2012. Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC M-PedeO (potassium salts of fatty acids) See label 2-3 NC VegolO (canola oil) See label 3 NC

Pest Biology: Scouting/Threshold: Cultural: • aphid injury to new growth is • insecticide penetration is diminished after leaf • avoid insecticides unless evident by petal fall curl necessary

Borers Conventional: For peachtree borer, only (Peachtree and Thionex 50WR (endosulfan) 4-5 lb 3 2 spray lower 18” of trunk. Flatheaded) Voliam XpressR (lambda-cyhalothrin/ 6-12 oz --- 3/28 chlorantraniliprole) Thionex 50W: can not be used on cherries after July (greater peachtree WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3 borer is rare on 31, 2012. cherry) Pest Biology: Scouting/Threshold: Cultural: • flatheaded borers attack trunks • prevent infestations in at-risk trees (young, • keep trees healthy with and limbs of stressed trees; exit stressed, or in decline) when adults are active optimal watering and holes are oval and about 1/4 in. in June and July nutrition diameter • only necessary when borer populations are • peachtree borers attack the known to be high in an area lower trunks of at-risk trees

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 90 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Cherry (Tart and Sweet)

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A FRUIT PRESENT (continued) Crown and root Conventional: Agri-Fos, Phostrol, rot Ridomil Gold SL (mefenoxam) 2 qt 3 4 Fosphite: provide (Phytophthora) protection of trees adjacent Reduced Risk/Organic: to dead trees; not to be used on dying trees. Fosphite (salts of phosphorous acid) 1-3 qt/100 g 2 33 Phostrol, Agri-Fos (mono- and dibasic sodium, See label 2 33 potassium, and ammonium phosphites)

Pest Biology: Scouting/Threshold: Cultural: • Phytophthora girdles the cambium • none • avoid excessive irrigation at the root collar, and causes • remove dead/dying wilting, limb dieback, and tree tree(s) and do not death in wet, poorly drained replant in the same soils site without improving

• spreads via root to root contact drainage Cherry

Conventional: Grasshoppers Dimilin 2L, Orthene Dimilin 2L (diflubenzuron) 2 oz 3 15 97: for non-crop areas Orthene 97R (acephate) 4 oz --- 1 only (borders, fence rows, Sevin 4F (carbaryl) 0.5-1.5 qt 2-3 1 roadsides, etc.).

Semaspore Bait: most Reduced Risk/Organic: effective on nymphs. Do O Semaspore Bait (Nosema locustae) 1 lb 2-4 --- not use if rain w/in 8 hours.

Sevin: use higher rate for mature grasshoppers or applications to dense foliage. Bait form available.

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs in the soil, • treat nymphs in spring along roads, ditches, • for more information, and hatch in spring; nymph to fences, and weedy areas; adults are more see Chapter 2, adult takes 5 molts difficult to treat Grasshoppers, page 13- 14.

Conventional: Leafrollers Altacor: max is 4 (European, Belt SC (flubendiamide) 3-4 oz 4 28 applications/season (9 fruittree, and oz per crop per acre per obliquebanded) Reduced Risk/Organic: year). Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 (these pests rarely Delegate WG (spinetoram) 4.5-7 oz 4 5 Dipel: works best when applied to exposed larvae need treatment in Dipel DFO (Bacillus thuringiensis sub. kurstaki) 0.5-2 lb 3 11 Colorado or Utah) (1/2 inch in size or less). EntrustO, Success (spinosad) See label 4 5 Intrepid 2F (methoxyfenozide) 8-16 oz 4 18

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 91 Cherry (Tart and Sweet) Chapter 6: Spray Tables

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A FRUIT PRESENT (continued) LEAFROLLERS (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs or immatures • look for rolled leaves with larvae inside • none on limbs; can feed on leaves and fruit, causing scarring

Leucostoma no effective fungicides canker (Cytospora) Pest Biology: Scouting/Threshold: Cultural: • cankers develop on trunk • look for oozing from trunk and limbs • keep trees growing and limbs in spring and in wet vigorously weather due to fungal infection • prune out dead • stressed and older trees are branches, especially most at risk those with cankers. Cherry Pear sawfly Conventional: One application should (Pear or Cherry Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 4 3/28 suffice. slug) chlorantraniliprole) WarriorR (lambda-cyhalothrin) 2.5-5 oz 2-3 3

Reduced Risk/Organic: Aza-DirectO, Azatin XL (azadirachtin) See label 3 UN

Pest Biology: Scouting/Threshold: Cultural: • larvae feed on the upper leaf • look for larvae on top of leaves in late June • none surface causing skeletonizing; trees can tolerate low populations

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 92 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Cherry (Tart and Sweet)

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A FRUIT PRESENT (continued) Powdery mildew Conventional: Pristine: do not make Elite 45 WP (tebuconazole) 4-8 oz 2 3 more than two sequential Gem 500 SC (trifloxystrobin) 1.9-3.8 oz 4 11 applications before Procure 50WS (triflumiziole) 8-16 oz 3-4 3 alternating to a labeled fungicide with a different Quilt Xcel (propiconazole/azoxystrobin) 14 oz 3-4 3/11 mode of action. Rally 40WSP (myclobutanil) 2.5-6.0 oz 3-4 3 Rubigan E.C. (fenarimol) 6-12 oz 3 3 Procure 50WS: max 96 Tilt (propiconazole) 4 oz 3 3 oz per acre per season. Topsin M 70 WDG (thiophanate-methyl) See label 2-3 1 Rally 40WSP: max 3.25 lb per acre per season. Reduced Risk/Organic: Abound (azoxystrobin) 12-15.5 oz 4 11 Rubigan E.C.: use a Armicarb, KaligreenO, MilStopO (potassium See label 1 NC surfactant when Rubigan bicarbonate) E.C. is applied alone.

Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 Cherry Serenade, Sonata, and Quintec (quinoxyfen) 7 oz 3-4 13 botanical oils: work best O Regalia (extract of Reynoutria sachalinensis) 2-4 qt --- NC when used early in the Serenade MAXO (Bacillus subtilis strain QST 713) 1-3 lb 1 NC season. SonataO (Bacillus pumilus strain QST 2808) 2-4 qt 2 NC SporanO (rosemary, clove, and thyme oils) .5-1 qt/25 g 1-2 NC TrilogyO (clarified extract of neem oil) See label 1-2 NC

Pest Biology: Scouting/Threshold: Cultural: • infections continue through • watch for new infections and treat • do not let irrigation land summer on foliage

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 93 Cherry (Tart and Sweet) Chapter 6: Spray Tables

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A FRUIT PRESENT (continued) Spider mites Conventional: Garlic Barrier AG+: Apollo SCR (clofentezine) 2-8 oz 4 10 insect repellent. Envidor 2 SC (spirodiclofen) 16-18 oz 4 23 Onager (hexythiazox) 12-24 oz 3 10 Vendex 50WP: make no more than two applications Savey 50 DF (hexythiazox) 3-6 oz 4 10 per season and apply no R Vendex 50WP (fenbutatin-oxide) 1.5-3 lb 3 12 more than 4.5 lb per acre per year. Reduced Risk/Organic: Acramite-50WS (bifenazate) 0.75-1 lb 4 UN Aza-DirectO (azadirachtin) 1-2 pints 2 UN BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC Garlic Barrier AG+O (garlic juice) See label 1-2 NC M-PedeO (potassium salts of fatty acids) See label 1-2 NC SucraShieldO (sucrose octanoate esters) See label --- NC VegolO (canola oil) See label 3 NC

Cherry Pest Biology: Scouting/Threshold: Cultural: • most likely to become a problem • look for small mites on undersides of leaves • avoid insecticides unless during hot, dry conditions in late in the lower interior canopy first necessary to protect summer when mites reproduce predators rapidly • prevent tree water stress

Spotted wing Conventional: Monitoring in individual drosophila Admire Pro (imidacloprid) - foliar application 2-2.8 oz 3 4 orchards will be important Malathion 5 EC (malathion) 4 pt 4 1 to know if this pest is (this pest has only Sevin 4F (carbaryl) 2-3 qt 4 1 present. Do not treat if not been found in a found. small area of Davis County, UT) Reduced Risk/Organic: Delegate WG (spinetoram) 4.5-7.0 oz 3 5 Success (spinosad) 4-8 oz 2 5

Pest Biology: Scouting/Threshold: Cultural: • first detected in Utah in Davis • adults can be monitored with liquid baits • destroy dropped and Co. in 2010 (yeast/sugar water or apple cider vinegar) over-ripened fruits • adult female has saw-like • only treat if adults are detected or as these are highly ovipositor and will lay eggs in neighboring crops are known to be infested attractive to this fly fruit

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 94 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Cherry (Tart and Sweet)

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A FRUIT PRESENT (continued) Western cherry Conventional: See page 12 for management fruit fly Admire Pro (imidacloprid) - foliar application 2-2.8 oz 3 4 information. Assail 30 SG (acetamiprid) 5.3-8.0 oz 3 4 Guthion SolupakR (azinphos-methyl) 1.5 lb 4 1 Admire Pro: max 14 oz/ acre/season for foliar apps. Imidan 70-W (phosmet) 2-2.5 lb 3 1 R Leverage 360 (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 Altacor: max is 4 Malathion 5 EC (malathion) 4 pt 4 1 applications/season (9 oz Sevin 4F (carbaryl) 2-3 qt 4 1 per crop per acre per year). Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 2 3/28 Delegate WG: max 4 chlorantraniliprole) applications per calendar R Warrior (lambda-cyhalothrin) 2.5-5 oz 2-3 3 year and 29 oz/ac/crop.

Reduced Risk/Organic: Entrust: max is 9 oz per Actara (thiamethoxam) 4.5-5.5 oz 3 4 acre per crop.

Altacor (chlorantraniliprole) 3.0-4.5 oz 2 28 Cherry GF-120: Because the Delegate WG (spinetoram) 4.5-7.0 oz 3 5 product is thick and has high EntrustO (spinosad) 1.25-2.5 oz 2 5 viscosity, it should be mixed Garlic Barrier AG+O (garlic juice) See label 1 NC with water outside the tank GF-120 NF Bait (spinosad) 10-20 oz 2-4 5 first, such as in a five-gallon Success (spinosad) 4-8 oz 2 5 bucket with an electric drill. Guthion: max use is 1.5 lb/acre; use cancelled after Sept. 30, 2012.

Imidan 70-W: tart cherries only.

Pest Biology: Scouting/Threshold: Cultural: • overwinter as pupae in the soil, • adults can be monitored with Pherocon AM® • landscape fabric and adults emerge from late spring traps plus ammonium carbonate lures dense ground covers through summer to lay eggs • treat by 5-7 days after first adult flies are under trees reduce within fruit; larvae (maggots) caught, when fruits in most exposed locations pupation and adult feed within fruits develop a salmon blush color emergence • adults cannot penetrate cherry skin for egg-laying until fruits turn a salmon blush color

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 95 Cherry (Tart and Sweet) Chapter 6: Spray Tables

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A PRE-HARVEST Powdery mildew Conventional: Procure 50WS: do not Elite 45 WP (tebuconazole) 4-8 oz 2 3 exceed 96 oz per acre per Procure 50WS (triflumizole) 8-16 oz 4 3 season. Rally 40WSP (myclobutanil) 2.5-6.0 oz 4 3 Rally 40WSP: do not Rubigan E.C. (fenarimol) 6-12 oz 3 3 apply more than 3.25 lb per acre per season. Reduced Risk/Organic: Abound (azoxystrobin) 12-15.5 oz 4 11 Cabrio EG (pyraclostrobin) 9.5 oz 3 11 Kaligreen, MilStopO (potassium bicarbonate) See label 1 NC Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC TrilogyO (clarified extract of neem oil) See label 1-2 NC

Pest Biology: Scouting/Threshold: Cultural: • infections on cherry stems make • watch for leaf, pedicel, and fruit infections • none fruit more difficult to shake off Cherry tree

Western cherry Conventional: All recommended products fruit fly Admire Pro (imidacloprid) - foliar application 2-2.8 oz 3 4 have 7 day PHI or less. See Assail 30 SG (acetamiprid) 5.3-8.0 oz 3 4 PHI table on pages 41-45. Imidan 70-W (phosmet) 2-2.5 lb 3 1 Admire Pro: do not apply R 2.4-2.8 oz 4 3/4 Leverage 360 (cyfluthrin/imidacloprid) more than 14 oz/acre per Sevin 4F (carbaryl) 2-3 qt 4 1 season for foliar application.

Reduced Risk/Organic: Imidan: tart cherries only. Delegate WG (spinetoram) 4.5-7.0 oz 3 5 EntrustO (spinosad) 1.25-2.5 oz 2 5 GF-120 NF BaitO (spinosad) 10-20 oz 2-4 5 Success (spinosad) 4-8 oz 2 5

Pest Biology: Scouting/Threshold: Cultural: • adult flies continue emerging • watch fruits for signs of infestation (shriveling, • landscape fabric and throughout summer, laying eggs collapse) dense groundcovers • maggots feed in fruit for 2-3 • continue to monitor with yellow sticky traps under trees interfere weeks, then drop to ground to with access of maggot pupate to soil

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 96 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Cherry (Tart and Sweet)

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A POST-HARVEST Powdery mildew Conventional: A 1-2% oil treatment can Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 help to prevent formation of Procure 50WS (triflumiziole) 8-16 oz 3-4 3 cleistothecia. Rally 40WSP (myclobutanil) 2.5-6.0 oz 3-4 3 Pristine: do not make Rubigan E.C. (fenarimol) 6-12 oz 3 3 more than two sequential Tilt (propiconazole) 4 oz 3 3 applications before alternating to a labeled Reduced Risk/Organic: fungicide with a different Abound (azoxystrobin) 12-15.5 oz 4 11 mode of action. Armicarb, KaligreenO, MilStopO (potassium See label 1 NC Procure 50WS: do not bicarbonate) exceed 96 oz per acre per O horticultural oil See label 3 NC season. Kaligreen, MilStopO (potassium bicarbonate) See label 1-2 NC Quintec (quinoxyfen) 7 oz 4 13 Rally 40WSP: do not O apply more than 3.25 lb per

Regalia (extract of Reynoutria sachalinensis) 2-4 qt --- NC Cherry acre per season. 80% ThiosperseO (sulfur) 4-30 lb 2 M2 Rubigan E.C.: use a surfactant when Rubigan E.C. is applied alone.

Pest Biology: Scouting/Threshold: Cultural: • overwintering fruiting bodies • treat before leaf drop to prevent cleistothecia • none (cleistothecia) form in early fall formation

Shothole borer Conventional: Thionex: only products Sevin 4F (carbaryl) See label 2 1 with old label can be used Thionex 50W (endosulfan) See label 2 1 on tart cherry up to July 30, 2012.

Pest Biology: Scouting/Threshold: Cultural: • second generation adults fly in • look for small (1/8 in. diameter) round • keep trees healthy with mid to late summer emergence holes in limbs and trunk adequate nutrition and • usually attack stressed trees irrigation

Spider mites Conventional: Vendex 50WP: make no Omite-30WS (propargite) 5-6 lb --- 12 more than two applications Vendex 50WPR (fenbutatin-oxide) 1.5-3 lb 3 12 per season and no more than 3 lb per acre per year. Reduced Risk/Organic: Acramite-50WS (bifenazate) 0.75-1 lb 4 un BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC horticultural oilO See label 2-3 NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 97 Cherry (Tart and Sweet) Chapter 6: Spray Tables

Cherry (tart and sweet) Pest Management Recommendations Rate M Pest Products (per Eff o Comments acre) A POST-HARVEST (continued) SPIDER MITES (continued) Pest Biology: Scouting/Threshold: Cultural: • spider mite activity slows in • look for stippling damage on foliage • provide adequate September water to trees into fall to reduce stress and susceptibility to mite injury

Western cherry Conventional: If fruit remains on the tree fruit fly Admire Pro (imidacloprid) - foliar application 2-2.8 oz 3 4 post-harvest, consider a final Dimethoate 2.67 (dimethoate) See label 4 1 treatment. Dimethoate is a good option. Reduced Risk/Organic: Admire Pro: do not apply Altacor (chlorantraniliprole) 3.0-4.5 oz 2 28 more than 14 oz/acre per Delegate 25 WG (spinetoram) 4.5-7.0 oz 3 5 season for foliar application.

Altacor: max is 4 Cherry applications/season (9 oz per crop per acre per year).

Delegate WG: max 4 applications per calendar year and 29 oz/ac/crop.

Pest Biology: Scouting/Threshold: Cultural: • adults continue to lay eggs as • none • none long as fruit are present

FALL Shothole Conventional: Fixed coppers or Ziram (Coryneum blight) Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 in fall are effective. Bravo Weather Stik (chlorothalonil) 3-4 pints 3 MS (this disease rarely Kocide 101, Kocide DF (copper hydroxide) See label 3 M1 occurs on cherry in Ziram 76DF (ziram) 5-6 lb 4 M3 Colorado or Utah)

Reduced Risk/Organic: C-O-C-S WDG (copper hydroxide) See label 3 M1 Nordox 75 WGO (cuprous oxide) 5-13 lb --- M1

Pest Biology: Scouting/Threshold: Cultural: • the fungus infects fresh leaf scars • treat at 50% leaf fall for good control and to • none for overwintering in fall protect overwintering buds

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 98 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

PEACH/NECTARINE Pest Phenology Calendar

Stages of Development

Major Calyx Calyx First Full Petal Post Bloom / Summer Post Dormant Pink Green Red Bloom Bloom Fall Harvest Pests June July August Sept.

Cat-facing Adults overwinter on orchard floor or move in from outside Adults, eggs, nymphs inside and outside Insects sources orchard

Coryneum Spores spread to young fruit with splash- Spores infect buds and Blight ing rain twigs

Green Nymphs / winged and wingless adults on Eggs on Eggs on limbs Peach Aphid new growth- move to non-fruit hosts limbs

Iron Apply to soil before foliage emerges; Repeat foliar applications on new growth Chlorosis

Leucostoma Conidia are spread in splashing rain (Cytospora)

Peach Silver Adult females in

Adult females in buds Adults, eggs, immatures in buds and on leaves Nectarine

Mite buds Peach, Peachtree Adults/ Eggs laid on Lar- Pupae (Crown) Larvae in trunk or under bark, usually below ground trunk/ Larvae bore into vae in in soil Borer trunk trunk Peach Twig Larvae tunnel in shoots; Adults, eggs, larvae in Larvae under Larvae under bark Borer Pupae in bark crevices fruit bark

Powdery Spores spread to fruit and new leaves as Mildew long as new growth present

Apple mildew conidia Rusty Spot infect young adults

San Jose Adults, crawlers, immatures on Immatures on Immatures on limbs Scale limbs, leaves, & fruit limbs

Adults at base Spider Mites Adults at base of tree Eggs, immatures, adults on ground cover and tree leaves of tree

Utah-Colorado Tree Fruit Production Guide 99 Peach/Nectarine Chapter 6: Spray Tables

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments DORMANT Bacterial canker Conventional: Champ Dry Prill, Champ Formula 2, Kocide See label 2 M1 (this disease rarely 101 (copper hydroxide) needs treatment in Colorado or Utah) Pest Biology: Scouting/Threshold: Cultural: • bacteria can live as non- • watch for milky colored gummosis • weak trees are more pathogen on plant surfaces, or susceptible overwinters in cankers which • prune out affected limbs begin oozing in spring; spread by splashing rain

Conventional: Peach Only one application needed; leaf curl Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 4 M5 dormant or at leaf fall are Champ Dry Prill, Champ Formula 2, Kocide See label 2-3 M1 the only opportunities for (this disease rarely 101 (copper hydroxide) treatment. needs treatment in Syllit FL (dodine) 3 pints --- M7 Colorado or Utah) Thiram Granuflo (thiram) 3.5 lb 4 M3 Syllit FL: for use on Ziram 76DF (ziram) 8-10 lb 4 M3 peaches only. Thiram Granuflo: for use Reduced Risk/Organic:

Peach, Peach, on peaches only. O Nectarine Nordox 75 WG (cuprous oxide) 5-13 lb 2-3 M1

Pest Biology: Scouting/Threshold: Cultural: • caused by fungus Taphrina • only treat if present the prior year (thick, • none deformans; treat in spring only curled red-yellow leaves in spring) • occurs sporadically with excessive spring rains

Conventional: Shothole Bravo: do not apply (Coryneum blight) Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 between shuck split and Champ Dry Prill, Champ Formula 2, Kocide See label 3 M1 harvest. 101 (copper hydroxide) Ziram 76DF (ziram) 6 lb 4 M3 Ziram 76DF: do not apply more than 56 lb per acre per Reduced Risk/Organic: crop cycle. Nordox 75 WGO (cuprous oxide) 5-13 lb 3 M1 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC

Pest Biology: Scouting/Threshold: Cultural: • fungus overwinters in dead buds • look for dead buds with a shiny ooze • prune out small cankers • spreads in warm, wet weather in during dormancy spring to leaves

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 100 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments DELAYED DORMANT (Swollen Bud to First Pink) Conventional: Aphid eggs Oil alone is sufficient for R O (Green peach Asana XL (esfenvalerate) + 2% oil 4.8-14.5 oz 4 3 suppression of aphid eggs. aphid, Plum aphid) Reduced Risk/Organic: 2% horticultural oilO See label 3-4 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs on limbs • if aphid populations were heavy the prior • none year, plan to apply a dormant treatment

Conventional: European red Oil alone is sufficient for mite and Brown Onager (hexythiazox) 12-24 oz 4 10 both mite species. mite eggs Savey 50 DF (hexythiazox) 3-6 oz 4 10 Savey 50 DF: do not make (these pests rarely Reduced Risk/Organic: more than one application/ need treatment) horticultural oilO See label 4 NC year. Pest Biology: Scouting/Threshold: Cultural: • both mite species overwinter as • if mites were severe in the prior season, • none Nectarine

eggs on limbs plan to treat now Peach,

Reduced Risk/Organic: Soft scale Centaur: max 2 Centaur WDG (buprofezin) + 2% oil 34.5-46 oz 4 16 applications/season. (this pest rarely 2% horticultural oilO see label 4 NC needs treatment) Pest Biology: Scouting/Threshold: Cultural: • overwinter as immatures • look for bumps on twigs • none

PRE-BLOOM Conventional: Peach twig Bt or spinosad is a good R borer Dimilin 2L (diflubenzuron) 12-16 oz 3 15 option to reduce the Imidan 70-W (phosmet) 4.25 lb 3 1 population. Two sprays 7 Thionex 50WR (endosulfan) 4-5 lb 4 2 days apart. Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 Altacor: max is 4 applications/season (9 oz per Reduced Risk/Organic: crop per acre per year). Agree WGO (Bacillus thuringiensis sub. 1-2 lb 4 11 aizawai strain GC-91) Dimilin 2L: do not apply Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 after petal fall. Delegate WG (spinetoram) 4.5-7.0 oz 3 5 Entrust: max is 9 oz per O Deliver (Bacillus thuringiensis sub. kurstaki) 0.5-2.0 lb 4 11 acre per crop. EntrustO (spinosad) 1.25-2.5 oz 3 5 Javelin WGO (Bacillus thuringiensis sub. 0.25-4.0 lb 4 11 Success: max is 29 oz per kurstaki strain SA-11) acre per crop. Success (spinosad) 4-8 oz 3 5

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 101 Peach/Nectarine Chapter 6: Spray Tables

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments PRE-BLOOM (continued) PEACH TWIG BORER (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as young larvae in • treat at this time based on last year’s • none at this time the tree and emerge to feed on injury level new growth at bud burst

Conventional: Shothole Bravo: do not apply (Coryneum blight) Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 between shuck split and Champ Dry Prill, Champ Formula 2, Kocide See label 3 M1 harvest. 101 (copper hydroxide) Gem 500 SC (trifloxystrobin) 2.9-3.8 oz --- 11 Quilt Xcel (propiconazole/azoxystrobin) 14 oz --- 3/11 Ziram 76DF (ziram) 6 lb 4 M3

Reduced Risk/Organic: Nordox 75 WGO (cuprous oxide) 5-13 lb 3 M1 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC

Pest Biology: Scouting/Threshold: Cultural: • fungus overwinters in dead buds • look for dead buds with a shiny ooze • prune out small cankers (look Peach, Peach, for dead buds with gumming) Nectarine • spreads in warm, wet weather in spring to leaves during dormancy

PETAL FALL Borers Conventional: (Shothole, Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 4/28 Flatheaded) chlorantraniliprole) WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 3 (minor pests in Colorado and UT) Pest Biology: Scouting/Threshold: Cultural: • attack trunks and limbs of trees • treatments only necessary when borer • maintain tree health to under stress populations are known to be high in an prevent infestation • prevent infestations in at-risk area • prune out dead/dying limbs trees (young, stressed, or in • look for sawdust-like frass, loose peeling immediately and remove decline) when adults are active bark, and exit holes debris from spring - mid summer

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 102 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments PETAL FALL (continued) Conventional: Lygus and Baythroid XL: maximum R Stink bugs Baythroid XL (beta-cyfluthrin) 2-2.4 oz 4 3 allowed per crop season is Carzol SP (formetanate hydrochloride) See label 3 1 5.6 oz per acre. Danitol 2.4 EC (fenpropathrin) 16-21.33 oz 3 3 Thionex 50WR (endosulfan) 4-5 lb 4 2 Carzol SP: do not apply more than 1.25 lb per acre; Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 3 4/28 do not apply after petal fall. Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 3/28 chlorantraniliprole) Warrior, Danitol: early WarriorR (lambda-cyhalothrin) 2.5-5 oz 4 3 season application of pyrethroids can disrupt Reduced Risk/Organic: beneficial mites. Beleaf 50 SG (flonicamid) 2-2.8 oz 4 9

Pest Biology: Scouting/Threshold: Cultural: • piercing mouthparts cause cat- • control in surrounding crops can keep • remove heavy weeds on facing injury to fruits plant bugs from moving to trees borders and attractive weeds • overwinter in alfalfa or other • use a sweep net to determine population in orchard ground cover

field crops and migrate to density Nectarine

nearby fruit trees when field Peach, crops are harvested

Conventional: Western flower Entrust: adding an adjuvant thrips Carzol SP (formetanate hydrochloride) 1-1.25 lb 3-4 1 will improve efficacy.

(mainly a problem Reduced Risk/Organic: Spinosad: toxic to bees on nectarines) EntrustO (spinosad) 1.25-2.5 oz 4 5 for 3 hours after treatment; Success (spinosad) 4-8 oz 4 5 spray after bees have been removed from the orchard.

Pest Biology: Scouting/Threshold: Cultural: • overwinter as adults in • shake flower clusters inside a paper • none protected areas on the ground cup or on dark paper to look for thrips and move to trees during bloom adults; check 5-6 clusters on several trees • feeding on young fruit results in • treat when there is more than 1 adult deep scarring and gumming per cluster

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 103 Peach/Nectarine Chapter 6: Spray Tables

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments SHUCK SPLIT Conventional: Aphids Admire Pro: do not apply (Green peach Admire Pro (imidacloprid) - foliar application 1.4-2.8 oz 4 4 during bloom or when bees aphid, Plum aphid) Admire Pro (imidacloprid) - soil application 7-10.5 oz 4 4 are active. Do not apply Assail 30 SG (acetamiprid) 2.5-5.3 oz 4 4 more than 10.5 oz/acre per Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 season for soil application, 8.4 oz/acre per season for Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 foliar application.

Reduced Risk/Organic: Allityn: only an insect Actara (thiamethoxam) 3-4 oz 4 4 repellant; not labeled to kill. Allityn (garlic juice extract) See label --- NC Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN horticultural oilO See label 4 NC M-PedeO (salts of fatty acids) See label 2-3 NC SucraShieldO (sucrose octanoate esters) See label --- NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs on limbs • check undersides of leaves on terminal • many beneficial insects help and become active in spring and twigs suppress aphids, so avoid cause severe leaf curl • look for curled leaves insecticides unless necessary • green peach aphid can

Peach, Peach, sometimes cause deep scarring Nectarine on nectarine fruit

Mating Disruption (organic): Peach Twig Hang Mating Disruption Borer Checkmate PTB-XL 200 3-4 NC (MD), after bloom, or after Isomate-PTB 200 --- NC the first moth has been caught in pheromone trap. For more info, see page 10. Pest Biology: Scouting/Threshold: Cultural: • summer generation larvae • hang traps at 250 DD in a non-MD site • hang dispensers in upper tunnel into fruit to determine first moth flight third of canopy

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 104 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments SHUCK SPLIT (continued) Conventional: Powdery Abound: start application mildew Adament 50 WG (tebuconazole/trifloxystrobin) 4-8 oz 3 3/11 at the onset of disease as Orbit, Tilt (propiconazole) See label 2 3 a protectant fungicide and Quash (metconazole) 3.5-4 oz --- 3 continue on a 7-14 day Rally 40WSP (myclobutanil) 2.5-6.0 oz 4 3 schedule.

Potassium bicarbonate: Reduced Risk/Organic: must be applied every 5-7 Abound (azoxystrobin) 12-15.5 oz 2 11 days while wet weather Armicarb, KaligreenO, (potassium bicarbonate) See label 1-2 NC persists to prevent infection. flowable/micronized sulfurO See label 3 M2 no more than 3 O See label 2 NC Quash: horticultural oil applications per year, most Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 2-3 7/11 effective prior to infection. RegaliaO (extract of R. sachalinensis) 2-4 qt --- NC Serenade ASOO, MAXO (Bacillus subtilis) See label 1 NC SonataO (Bacillus pumilus strain QST 2808) 2-4 qt --- NC TrilogyO (clarified extract of neem oil) See label 1 NC

Pest Biology: Scouting/Threshold: Cultural: Nectarine • apple powdery mildew causes • treat when fruit is the size of a pea, • none Peach, “peach rusty spot” especially if weather is wet and mildew • peach powdery mildew attacks was a problem the prior year leaves and fruit • treat from post-bloom through pit hardening Conventional: Shothole Abound: start application (Coryneum blight) Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 at the onset of disease as Bravo Weather Stik (chlorothalonil) 3-4 pints 3 M5 a protectant fungicide and Captan 50 WP (captan) See label 3 M4 continue on a 7-14 day Gem 500 SC (trifloxystrobin) 2.9-3.8 oz --- 11 schedule. Quilt Xcel (propiconazole/azoxystrobin) 14 oz --- 3/11 Bravo: do not use after Ziram 76DF (ziram) 6 lb 4 M3 shuck split.

Reduced Risk/Organic: Abound (azoxystrobin) 12-15.5 oz 2 11 Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC TrilogyO (clarified extract of neem oil) See label 1 NC

Pest Biology: Scouting/Threshold: Cultural: • fungus spreads from leaf • look for small purple to brown spots on • none infections to fruit leaves and purple spots on fruit and new shoots

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 105 Peach/Nectarine Chapter 6: Spray Tables

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT Conventional: European red Apollo SC: works against mite and Brown Apollo SC (clofentezine) 2-8 oz 4 10 eggs, and is most effective mite Envidor 2 SC (spirodiclofen) 16-18 oz 4 23 when applied when Nexter (pyridaben) 4.4-5.2 oz 4 21 population size is low. (these pests rarely Onager (hexythiazox) 12-24 oz --- 10 need treatment Savey 50 DF (hexythiazox) 3-6 oz 4 10 Nexter: most effective in commercial when applied when orchards) population size is low. Only Reduced Risk/Organic: two applications allowed per Acramite-50WS (bifenazate) 0.75-1 lb 4 un season. BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC horticultural oilO See label 2-3 NC

Pest Biology: Scouting/Threshold: Cultural: • mites become active in spring, • brown mites occur sporadically in Utah • none and thrive in cool conditions orchards; look for small reddish-brown • brown mites feed on leaves at dots on lower leaf surface or shake night and rest on twigs at day branch over paper

Conventional: Grasshoppers Dimilin 2L, Orthene Dimilin 2L (diflubenzuron) 2 oz 3 15 97: for non-crop areas Peach, Peach, Orthene 97R (acephate) 4 oz --- 1 Nectarine only (borders, fence rows, Sevin 4F (carbaryl) 0.5-1.5 qt 2-3 1 roadsides, etc.)

Semaspore Bait: most Reduced Risk/Organic: effective on nymphs. Do not O Semaspore Bait (Nosema locustae) 1 lb 2-4 --- use if rain within 8 hours.

Sevin: use higher rate for mature grasshoppers or applications to dense foliage. Bait form available.

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs in the soil, • treat nymphs in spring along roads, • for more information, see and hatch in spring; transition ditches, fences, and weedy areas; adults Chapter 2, Grasshoppers, from nymph to adult takes 5 are more difficult to treat pages 13-14 molts

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 106 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Greater Only lower 12-18” of trunk Peachtree borer Asana XL (esfenvalerate) 4.8-14.5 oz 3 3 should be sprayed. (Crown borer, Lorsban-4ER (chlorpyrifos) 1.5-4 pt 4 1 Trunk borer) Pounce 3.2 ECR (permethrin) 4-12 oz 3 3 Lorsban-4E: only spray Thionex 50WR (endosulfan) 4-5 lb 3 2 trunk; do not allow spray on foliage or fruit. Voliam XpressR (lambda-cyhalothrin/ 6-12 oz --- 3/28 chlorantraniliprole) Mating disruption is very WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3 effective and lasts all season. Hang dispensers right after Mating Disruption (organic): first trap catch or by early July. See page 10 for more Isomate-P 100 4 NC info.

Pest Biology: Scouting/Threshold: Cultural: • adults emerge in mid to late • hang pheromone traps in early June to • prevent dense weed growth June in northern Utah (3-4 determine first moth activity around base of trees weeks earlier in southern Utah) • apply treatments to susceptible trees and continue flight through after moth flight and maintain protection September

through mid September Nectarine Peach, Conventional: Leafrollers Altacor: max is 4 (European, Belt SC (flubendiamide) 3-4 oz 4 28 applications/season (9 oz per fruittree, and crop per acre per year). obliquebanded) Reduced Risk/Organic: Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Dipel: works best when (these pests rarely Delegate WG (spinetoram) 4.5-7 oz 4 5 applied to exposed larvae (1/2 inch in size or less). need treatment in Dipel DFO (Bacillus thuringiensis sub. kurstaki) 0.5-2 lb 3 11 Colorado or Utah) EntrustO, Success (spinosad) See label 4 5 Intrepid 2F (methoxyfenozide) 8-16 oz 4 18

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs or • look for rolled leaves with larvae inside • none immatures on limbs; can feed on leaves and fruit, causing scarring

Leucostoma no fungicides are effective; only cultural controls canker (Cytospora)

Pest Biology: Scouting/Threshold: Cultural: • cankers develop on trunk and • watch for gummosis on scaffold limbs • keep trees growing vigorously limbs and ooze gum • prune out dead branches, • stressed trees, and trees with especially those with cankers winter injury are most at risk

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 107 Peach/Nectarine Chapter 6: Spray Tables

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Lilac root Belay: label expires Oct. 2, weevil Assail 30 SG (acetamiprid) 5.3-8.0 oz --- 4 2012. Max 12 oz/season. Belay (clothianodin) 6 oz --- 4 Sevin 4F (carbaryl) 2-3 qt --- 1 Botanigard: must contact Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3-4 3/28 the insect; spray at night chlorantraniliprole) within one day of mixing. Nematodes: targets larvae; Reduced Risk/Organic: apply to moist soil and Botanigard 22WP (Beauveria bassiana) 1-3 lb/100 g --- NC keep soil moist for 14 days; NemaSeekO, others (Heterorhabditis See label 2-3 NC products have 2 week shelf bacteriophora) life.

Pest Biology: Scouting/Threshold: Cultural: • larval grubs feed on roots and • starting in late spring, monitor lowest • none adults emerge in late spring to leaves for the first sign of leaf feeding; feed on leaf edges at night treat at this time

Conventional: Lygus and Baythroid XL: maximum R Stink bugs Baythroid XL (beta-cyfluthrin) 2-2.4 oz 4 3 allowed per crop season is Belay (clothianidin) 6 oz --- 4 5.6 oz per acre.

Peach, Peach, Carzol SP (formetanate hydrochloride) See label 3 1

Nectarine Danitol 2.4 EC (fenpropathrin) 16-21.33 oz 3 3 Belay: label expires Oct. 2, 2012. Max 12 oz/season. Thionex 50WR (endosulfan) 4-5 lb 4 2 Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 3 4/28 Carzol SP: do not apply Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 3/28 more than 1.25 lb per acre; chlorantraniliprole) do not apply after petal fall. WarriorR (lambda-cyhalothrin) 2.5-5 oz 4 3 Warrior, Danitol: early season application of Reduced Risk/Organic: pyrethroids can disrupt Beleaf 50 SG (flonicamid) 2-2.8 oz 4 9 beneficial mites.

Pest Biology: Scouting/Threshold: Cultural: • piercing mouthparts cause cat- • control in surrounding crops can keep • remove heavy weeds on facing injury to fruits plant bugs from moving to trees borders and attractive weeds • may migrate to fruits when • use a sweep net to determine population in orchard ground cover nearby fields are harvested or density weeds dry

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 108 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Peach twig One or two sprays needed borer Belt SC (flubendiamide) 3-4 oz 3-4 28 per generation, dependent on Danitol 2.4 EC (fenpropathrin) 10.6-21.3 oz 2-3 3 pest pressure. Imidan 70-W (phosmet) 4.25 lb 3 1 Tourismo (buprofezin/flubendiamide) 10-14 oz 3 16/28 Altacor: max is 4 Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 3-4 4/28 applications/season (9 oz per crop per acre per year). Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3-4 3/28 chlorantraniliprole) Bt: must be consumed by WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3 larvae and applied every 5-7 days. Reduced Risk/Organic: Danitol 2.4 EC: do O 11 Agree WG (Bacillus thuringiensis sub. 1-2 lb 2-3 not make more than two aizawai strain GC-91) applications per season. Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN Delegate WG: max 4 Delegate WG (spinetoram) 4.5-7.0 oz 3 5 applications per calendar year and 29 oz/ac/crop. DeliverO (Bacillus thuringiensis sub. kurstaki 0.5-2.0 lb 2-3 11 strain SA-12)

Entrust: max is 9 oz per Nectarine O Entrust (spinosad) 1.25-2.5 oz 2-3 5 acre per crop. Peach, Intrepid 2F (methoxyfenozide) 8-16 oz 2-3 18 Javelin WGO (Bacillus thuringiensis sub. 0.25-4.0 lb 2-3 11 Success: max is 29 oz per acre per crop. kurstaki strain SA-11) O Neemix 4.5 (azadirachtin) 7-16 oz 2 UN Tourismo: max is 3 Success (spinosad) 4-8 oz 2-3 5 applications per crop season.

Pest Biology: Scouting/Threshold: Cultural: • summer generation larvae • hang pheromone traps at 250 DD to • prune out “flagged” shoots to tunnel into fruit determine first moth flight remove overwintering larvae • time fruit protective sprays at 300-400 degree-days after first adult moth activity

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 109 Peach/Nectarine Chapter 6: Spray Tables

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Peach silver Garlic Barrier AG+: insect mite Kelthane 50WSP (dicofol) See label 3-4 UN repellent. Nexter (pyridaben) 5.2-10.7 oz 4 21 Nexter: works best when Reduced Risk/Organic: applied before mites reach BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC economic threshold. Only two applications allowed per O See label 3 NC horticultural oil season. M-PedeO (potassium salts of fatty acids) See label 1-2 NC SucraShieldO (sucrose octanoate esters) See label --- NC Omite-30WS: registered only on nectarine unless non- bearing application. Pest Biology: Scouting/Threshold: Cultural: • an eriophyid mite, causing • only treat if symptoms are severe • none “silvering” on leaves

Conventional: Shothole Abound: use as a protectant (Coryneum blight) Captan 50 WP (captan) See label 3 M4 and continue on a 7-14 day Gem 500 SC (trifloxystrobin) 2.9-3.8 oz --- 11 schedule when needed. Quilt Xcel (propiconazole/azoxystrobin) 14 oz --- 3/11 Ziram 76DF (ziram) 6 lb 3 M3 Peach, Peach,

Nectarine Reduced Risk/Organic: Abound (azoxystrobin) 12-15.5 oz 2 11 Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC TrilogyO (clarified extract of neem oil) See label 1 NC

Pest Biology: Scouting/Threshold: Cultural: • fruit is susceptible to infection • to prevent spread, treat pre-harvest only • none up to harvest (causing sunken if 4 or more hours of rain or moisture rot in cold storage) occurs frequently • four hours of moisture are • watch leaves and fruit throughout the needed for infection season for lesions

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 110 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Spider mites Nexter: works best when R Apollo SC (clofentezine) 2-8 oz 4 10 applied before mites reach Envidor 2 SC (spirodiclofen) 16-18 oz 4 23 economic threshold. Only Nexter (pyridaben) 6.6-10.7 oz 4 21 two applications allowed per Omite-30WS (propargite) 5-9 lb 4 12 season. Onager (hexythiazox) 12-24 oz 3 10 Omite-30WS: registered Savey 50 DF (hexythiazox) 3-6 oz 4 10 only on nectarine unless non- R Vendex 50WP (fenbutatin-oxide) 1-2 lb 3 12 bearing.

Reduced Risk/Organic: Savey 50 DF: do not make more than one application Acramite-50WS (bifenazate) 0.75-1 lb 4 UN per year. BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC horticultural oilO See label 2-3 NC Vendex 50WP: max two M-PedeO (potassium salts of fatty acids) See label 1-2 NC applications per year (3 lb SucraShieldO (sucrose octanoate esters) See label --- NC per acre per year).

Pest Biology: Scouting/Threshold: Cultural:

• most likely to become a • look for mite activity on lowest, interior • to protect predatory spider Nectarine

problem during hot, dry leaves first mites, avoid insecticides Peach, conditions in late summer (especially pyrethroids) unless necessary Spotted wing Conventional: Monitoring in individual drosophila Admire Pro (imidacloprid) - foliar application 2-2.8 oz 3 4 orchards will be important to Malathion 5 EC (malathion) 4 pt 4 1 know if this pest is present. (this pest has only Sevin 4F (carbaryl) 2-3 qt 4 1 Do not treat if not found. been found in a small area of Davis Reduced Risk/Organic: County, UT) Delegate WG (spinetoram) 4.5-7.0 oz 3 5 Success (spinosad) 4-8 oz 2 5

Pest Biology: Scouting/Threshold: Cultural: • first detected in Utah in Davis • adults can be monitored with liquid baits • destroy dropped and over- Co. in 2010 (yeast/sugar water or apple cider vinegar) ripened fruits as these are • adult female has saw-like • only treat if adults are detected or highly attractive to this fly ovipositor and will lay eggs in neighboring crops are known to be unripe fruit infested

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 111 Peach/Nectarine Chapter 6: Spray Tables

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Walnut husk fly One or two sprays may be Sevin 4F (carbaryl) 2-3 qt 3 1 needed, 14 days apart.

Reduced Risk/Organic: Bugitol: 96 oz/100 gal per Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC acre for heavy infestations. Delegate WG (spinetoram) 4.5-7.0 oz 3 5 Garlic Barrier AG+: insect Entrust (spinosad) 1.25-2.5 oz 2-3 5 repellent. Garlic Barrier AG+O (garlic juice) See label 1 NC GF-120 NF (spinosad+bait) See label 3 5 Spinosad (Entrust, Success): Success (spinosad) 4-10 oz 2-3 5 works best when mixed with bait, or use GF-120.

Pest Biology: Scouting/Threshold: Cultural: • adults start emerging in mid- • adults can be monitored with Pherocon • none summer and lay eggs in fruit AM traps • risk is greater where unsprayed • treat by seven days after adult flies are walnut trees are near peach or caught or beginning in late July nectarine trees

PRE-HARVEST Peach, Peach,

Nectarine Conventional: Earwigs Sevin 80S & Sevin 4F: Sevin 4F (carbaryl) 2-3 qt 3 1 make applications no more Sevin 80S (carbaryl) 2.5-3.75 lb 3 1 than once every seven days WarriorR (lambda-cyhalothrin) 1.3-2.5 oz 3 3 and no more than three times per crop. Reduced Risk/Organic: Warrior: 14 day PHI. EntrustO, Success (spinosad) See label 3 5

Pest Biology: Scouting/Threshold: Cultural: • adults climb trees and feed on • look for damage where fruit touch, or • band tree at trunk with sticky ripening fruit about 2 weeks under leaves; earwigs leave behind black adhesive before maturity droppings • they can also be beneficial • tie corrugated cardboard rolls to trunks predators of other insects to monitor

FALL Conventional: Bacterial canker Treat limbs before frost. Kocide 1010 (copper hydroxide) 8-16 lb 2 M1

Reduced Risk/Organic: copper sulfateO 16-25 lb 2 M1 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 112 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Peach/Nectarine

Peach/nectarine Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FALL (continued) BACTERIAL CANKER (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinters in wood and goes • none • none dormant; sometimes buds are killed in early winter

Conventional: Peach silver Nexter: only two mite Kelthane 50WSP (dicofol) See label 3-4 UN applications allowed per Nexter (pyridaben) 5.2-10.7 oz 4 21 season.

Reduced Risk/Organic: Omite-30WS: registered 80% ThiosperseO (sulfur) 4-30 lb 2-3 M2 only on nectarine unless non- bearing.

Pest Biology: Scouting/Threshold: Cultural: • an eriophyid mite, causing • only if silver mite problem is severe or • none “silvering” on leaves persists Nectarine

Conventional: Peach, Shothole Bravo: can only be used (Coryneum blight) Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 after harvest and before Bravo Weather Stik (chlorothalonil) 3-4 pints 3 M5 shuck-split. Captan 50 WP (captan) See label 3 M4 Ziram 76DF (ziram) 6 lb 3 M3 Fixed coppers or Ziram are effective. Reduced Risk/Organic: C-O-C-S WDG (copper hydroxide) See label 3 M1 Nordox 75 WGO (cuprous oxide) 5-13 lb 3 M1

Pest Biology: Scouting/Threshold: Cultural: • fungus infects fresh leaf scars at • treat at 50% leaf fall for good control and • none leaf fall and overwinters as small to protect overwintering buds cankers which ooze in spring

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 113 Apricot Chapter 6: Spray Tables

APRICOT Pest Phenology Calendar

Stages of Development

Major Calyx Calyx First Full Petal Post Bloom / Summer Post Dormant Pink Green Red Bloom Bloom Fall Harvest Pests June July Aug. Sept.

Cat-facing Adults overwinter on orchard floor or move in from outside Adults, eggs, nymphs inside and outside Insects sources orchard

Coryneum Spores spread to young fruit with splashing Spores infect buds and Blight rain twigs

Green Peach Nymphs / winged and wingless adults on Eggs on Eggs on limbs Aphid new growth- move to non-fruit hosts limbs

Iron Apply to soil before foliage emerges; Repeat foliar applications on new growth Chlorosis

Leucostoma Conidia are spread in splashing rain (Cytospora)

Peach Silver Adult females in Adult females in buds Adults, eggs, immatures in buds and on leaves Mite buds Peach Tree Larvae Pupae Adults/ Eggs laid on trunk/ (Crown) Larvae in trunk or under bark, usually below ground in in soil Larvae bore into trunk Borer trunk Peach Twig Larvae tunnel in shoots; Adults, eggs, larvae in Larvae under Larvae under bark Borer pupae in bark crevices fruit bark Apricot Powdery Spores spread to fruit and new leaves as Mildew long as new growth present

Apple mildew conidia Rusty Spot infect young adults

San Jose Adults, crawlers, immatures on Immatures on Immatures on limbs Scale limbs, leaves, & fruit limbs

Adults at base of Spider Mites Adults at base of tree Eggs, immatures, adults on ground cover and tree leaves tree

114 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apricot

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments DORMANT Conventional: Bacterial Copper: apply as a dormant canker Champ Dry Prill, Champ Formula 2, Kocide See label 2 M1 application before bud swell. 101 (copper hydroxide)

Reduced Risk/Organic: Nordox 75 WGO (cuprous oxide) 8-10 lb 2 M1 RegaliaO (extract of R. sachalinensis) 2-4 qt --- NC

Pest Biology: Scouting/Threshold: Cultural: • cankers start to ooze in spring • none • prune out cankers before warm weather

Conventional: Shothole Copper: apply as a dormant (Coryneum Champ Dry Prill, Champ Formula 2, Kocide See label 2 M1 application before bud swell. blight) 101 (copper hydroxide)

Reduced Risk/Organic: Nordox 75 WGO (cuprous oxide) 5-13 lb 2 M1

Pest Biology: Scouting/Threshold: Cultural: • fungus overwinters in dead • look for dead buds with oozing • prune out dead twigs buds Apricot

DELAYED DORMANT (Swollen Bud to First White) Conventional: Aphid eggs Diazinon 50W: max is one Assail 30 SG (acetamiprid) 2.5-5.3 oz 4 4 application at dormant timing, (aphids uncommon Diazinon 50WR (diazinon) + oil 1 lb 4 1 and one in the summer. on apricot in Colorado or Utah Reduced Risk/Organic: commercial orchards) horticultural oil, 2%O See label 4 NC

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs on limbs • treat if aphids a problem the previous year • none

Conventional: European red Savey 50 DF: do not apply mite eggs Onager (hexythiazox) 12-24 oz 4 10 more than once/year. Savey 50 DF (hexythiazox) 3-6 oz 4 10 (this pest rarely needs treatment in Reduced Risk/Organic: Colorado or Utah) BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC horticultural oilO See label 4 NC Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs on limbs • treat if a problem the previous year • none

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 115 Apricot Chapter 6: Spray Tables

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments PETAL FALL TO SHUCK SPLIT Borer Conventional: (Shothole, Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 4/28 Flatheaded) chlorantraniliprole) WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 3 (minor pests in Colorado and UT)

Pest Biology: Scouting/Threshold: Cultural: • borers attack trunks and limbs • treatments only necessary when borer • maintain tree health to prevent of trees under stress populations are known to be high in an infestation • prevent infestations in at-risk area • prune out dead/dying limbs trees (young, stressed, or in • look for sawdust-like frass, loose immediately and remove debris decline) when adults are active peeling bark, and exit holes from spring to mid summer

Conventional: Cat-facing Only one application is needed insects Assail 30 SG (acetamiprid) 5.3-8.0 oz 2-3 4 if timing is good. (Lygus bug, Stink Danitol 2.4 EC (fenpropathrin) 10.6-21.3 oz 3 3 bug) Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 3-4 3/4 Danitol 2.4 EC: do not make Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 3 4/28 more than two applications per season. Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 4 3/28 chlorantraniliprole) WarriorR (lambda-cyhalothrin) 2.5-5 oz 4 3

Apricot Reduced Risk/Organic: Aza-DirectO (azadirachtin) 1-2 pints 2 UN Neemix 4.5O (azadirachtin) 7-16 oz 2 UN

Pest Biology: Scouting/Threshold: Cultural: • populations are highest where • prevent piercing-sucking bugs from feeding • remove heavy weed zones orchards border alfalfa fields; on new fruit if cat-facing injury was a bugs may move to developing problem in the previous year or if high fruit to feed populations of bugs are observed now

Conventional: Leafrollers Altacor: do not make more (European, Belt SC (flubendiamide) 3-4 oz 4 28 than 4 applications per season fruittree, and and do not apply more than 9 obliquebanded) Reduced Risk/Organic: oz per crop per acre per year. Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 (these pests rarely Delegate WG (spinetoram) 4.5-7 oz 4 5 Dipel: works best when applied to exposed larvae (1/2 need treatment in Dipel DFO (Bacillus thuringiensis sub. 0.5-2 lb 3 11 Colorado or Utah) inch in size or less). kurstaki) EntrustO, Success (spinosad) See label 4 5 Intrepid 2F (methoxyfenozide) 8-16 oz 4 18

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 116 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apricot

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments PETAL FALL TO SHUCK SPLIT (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs or • look for rolled leaves with larvae inside • none immatures on limbs; can feed on leaves and fruit, causing scarring

Conventional: Peach twig Larvae emerge from protected borer Assail 30 SG (acetamiprid) 5.3-8.0 oz 3 4 areas at this time, and Dimilin 2LR (diflubenzuron) 12-16 oz 3 15 treating with a Bt product is Imidan 70-W (phosmet) 4.25 lb 3 1 a good option to reduce the Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 population. WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3 Altacor: max 4 applications per season and 9 oz per crop Reduced Risk/Organic: per acre per year. Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN Bugitol: apply 96 oz/100 gal Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC per acre for heavy infestations. Delegate WG (spinetoram) 4.5-7.0 oz 4 5 Delegate WG: max 4 O Deliver (Bacillus thuringiensis sub. kurstaki 0.5-2.0 lb 4 11 applications per calendar year strain SA-12) and 29 oz/acre per crop. EntrustO (spinosad) 1.25-2.5 oz 3 5 Garlic Barrier AG+O (garlic juice) See label --- NC Dimilin 2L: do not apply after

petal fall. Apricot Intrepid 2F (methoxyfenozide) 8-16 oz 3 18 O Javelin WG (Bacillus thuringiensis sub. 0.25-4 lb 4 11 Entrust: do not apply more kurstaki strain SA-11) than a total of 9 oz/acre/crop. Neemix 4.5O (azadirachtin) 7-16 oz 2 UN Success (spinosad) 4-8 oz 3 5 Garlic Barrier AG+: insect repellent.

Success: do not apply more than a total of 29 oz per acre per crop. Pest Biology: Scouting/Threshold: Cultural: • overwinter as young larvae in • treat at this timing if PTB was a problem last • none at this time protected nests on twigs year

Mating Disruption (organic): Peach Twig Hang Mating Disruption Borer Checkmate PTB-XL 200 3-4 NC (MD), after bloom, or after the Isomate-PTB 200 --- NC first moth has been caught. For more info, see page 10. Pest Biology: Scouting/Threshold: Cultural: • summer generation larvae • hang pheromone traps in a non-MD site at • hang MD dispensers in tunnel into fruit 250 DD to determine first moth flight upper third of canopy

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 117 Apricot Chapter 6: Spray Tables

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments PETAL FALL TO SHUCK SPLIT (continued) Conventional: Powdery Abound: start application mildew Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 at the onset of disease as a Rally 40WSP (myclobutanil) 2.5-6.0 oz 4 3 protectant and continue on a (this disease rarely Tilt (propiconazole) 4 oz 3 3 7-14 day schedule. needs treatment on apricot in Reduced Risk/Organic: Sonata, Serenade: biologicals Colorado or Utah) work best in early stages or Abound (azoxystrobin) 12-15.5 oz 3 11 under low pressure. horticultural oilO See label 2 NC KaligreenO, MilStopO (potassium See label 2 NC Tilt: most effective when bicarbonate) applied and allowed to dry RegaliaO (extract of R. sachalinensis) 2-4 qt --- NC before rainfall. Serenade MAXO (Bacillus subtilis strain QST 1-3 lb 1 NC 713) SonataO (Bacillus pumilus strain QST 2808) 2-4 qt 1 NC TrilogyO (clarified extract of neem oil) See label 1 NC

Pest Biology: Scouting/Threshold: Cultural: • causes red spider-web marks • treat when fruit is the size of a pea • none or brown spots on fruit of some cultivars growing near mildew-susceptible apples

Conventional: Shothole Abound: start application (Coryneum Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 at the onset of disease as a

Apricot blight) Captan 50 WP (captan) See label 3 M4 protectant and continue on a Gem 500 SC (trifloxystrobin) 2.9-3.8 oz --- 11 7-14 day schedule. Quilt Xcel (propiconazole/azoxystrobin) 14 oz --- 3/11 Ziram 76DF (ziram) 6 lb 4 M3 Bravo: do not apply after shuck split.

Reduced Risk/Organic: Pristine: do not make more Abound (azoxystrobin) 12-15.5 oz 3 11 than two sequential applications Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 before alternating to a labeled RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC fungicide with a different mode of action. TrilogyO (clarified extract of neem oil) See label 1 NC

Pest Biology: Scouting/Threshold: Cultural: • protect new leaves and fruit at • watch for small purple spots on leaves and • none this time new shoots

Conventional: Soft scale Centaur: max 2 applications/ Centaur WDG (buprofezin) 34.5-46 oz 4 16 season. (this pest rarely needs treatment Reduced Risk/Organic: Esteem 35 WP: use with oil. in commercial Esteem 35 WP (pyriproxyfen) 4-5 oz 4 7 orchards) Golden Pest Spray OilO (soybean oil) 4-6 gal 3 NC horticultural oilO See label 3 NC

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 118 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apricot

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments PETAL FALL TO SHUCK SPLIT (continued) SOFT SCALE (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as immatures on • look for raised bumps on limbs and twigs • none limbs

FRUIT PRESENT Conventional: Grasshoppers Dimilin 2L, Orthene 97: for Dimilin 2L (diflubenzuron) 2 oz 3 15 non-crop areas only (borders, Orthene 97R (acephate) 4 oz --- 1 fence rows, roadsides, etc.) Sevin 4F (carbaryl) 0.5-1.5 qt 2-3 1 Semaspore Bait: most effective on nymphs. Do not Reduced Risk/Organic: use if it will rain within 8 hours. Semaspore BaitO (Nosema locustae) 1 lb 2-4 --- Sevin: use higher rate for mature grasshoppers or applications to dense foliage. Bait form available.

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs in the soil, • treat nymphs in spring along roads, ditches, • for more information, see and hatch in spring; nymph to fences, and weedy areas; adults are more Chapter 2, Grasshoppers,

adult takes 5 molts difficult to treat pages 13-14. Apricot

Conventional: Greater Two sprays needed on lower peachtree Thionex 3EC (endosulfan) See label 3 2 trunk: early July and early borer Voliam XpressR (lambda-cyhalothrin/ 6-12 oz --- 3/28 August. (Crown borer, chlorantraniliprole) Trunk borer) WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3 Mating disruption: hang dispensers right after first trap catch; one application lasts all Mating Disruption (organic): season. Isomate-P 100 4 NC

Pest Biology: Scouting/Threshold: Cultural: • adults emerge in late June in • hang pheromone traps in mid June • keep trees healthy northern Utah (3-4 weeks • avoid dense weed growth earlier in southern Utah) at tree base

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 119 Apricot Chapter 6: Spray Tables

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Peach twig One or two sprays needed, borer Assail 30 SG (acetamiprid) 5.3-8.0 oz 3 4 depending on pest pressure. Belt SC (flubendiamide) 3-4 oz 3-4 28 Danitol 2.4 EC (fenpropathrin) 10.6-21.3 oz 2 3 Altacor: max 4 applications Imidan 70-W (phosmet) 4.25 lb 3 1 per season and 9 oz per crop Tourismo (buprofezin/flubendiamide) 10-14 oz --- 16/28 per acre per year. Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 Bugitol: apply 96 oz/100 gal R Voliam Xpress (lambda-cyhalothrin/ 6-12 oz 4 3/28 per acre for heavy infestations. chlorantraniliprole) WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3 Danitol 2.4 EC: do not make more than two applications per season. Reduced Risk/Organic: Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Delegate WG: max 4 Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN applications per calendar year Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC and 29 oz/ac/crop. Delegate WG (spinetoram) 4.5-7.0 oz 3-4 5 Entrust: do not apply more O 0.5-2.0 lb 2 11 Deliver (Bacillus thuringiensis sub. kurstaki than a total of 9 oz per acre per strain SA-12) crop. EntrustO (spinosad) 1.25-2.5 oz 2-3 5 Garlic Barrier AG+O (garlic juice) See label --- NC Garlic Barrier AG+: insect Intrepid 2F (methoxyfenozide) 8-16 oz 2 18 repellent. O 7-16 oz 2 UN Neemix 4.5 (azadirachtin) Success: do not apply more Success (spinosad) 4-8 oz 2-3 5 than a total of 29 oz per acre per crop.

Apricot Mating Disruption (organic): Checkmate PTB-XL 200 3-4 NC Tourismo: do not apply more Isomate-PTB 200 --- NC than 3 times per crop season.

Pest Biology: Scouting/Threshold: Cultural: • larvae prefer to tunnel into • time fruit protective sprays at 300-400 • none new shoots and tender twigs in degree-days after first adult moth activity first generation

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 120 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Apricot

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Powdery Abound: use as a protectant mildew Rally 40WSP (myclobutanil) 2.5-6.0 oz 4 3 at 7-14 day intervals when Tilt (propiconazole) 4 oz 3 3 necessary. (this disease rarely needs treatment Reduced Risk/Organic: Sonata, Serenade: biologicals on apricot in Abound (azoxystrobin) 12-15.5 oz 3 11 work best in early stages or Colorado or Utah) under low pressure. horticultural oilO See label 2 NC O O Kaligreen , MilStop (potassium See label 2 NC Tilt: most effective when bicarbonate) applied and allowed to dry Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 before rainfall. RegaliaO (extract of R. sachalinensis) 2-4 qt --- NC Serenade MAXO (Bacillus subtilis strain QST 713) 1-3 lb 1 NC SonataO (Bacillus pumilus strain QST 2808) 2-4 qt 1 NC TrilogyO (clarified extract of neem oil) See label 1 NC

Pest Biology: Scouting/Threshold: Cultural: • causes red spider-web marks • watch for white lesions on fruit and leaves; • none or brown spots on some no threshold developed cultivars growing near mildew- susceptible apples

Conventional: Shothole Abound: use as a protectant Apricot (Coryneum Captan 50 WP (captan) See label 3 M4 and continue on a 7-14 day blight) Gem 500 SC (trifloxystrobin) 2.9-3.8 oz --- 11 schedule when needed. Quilt Xcel (propiconazole/azoxystrobin) 14 oz --- 3/11 Ziram 76DF (ziram) 6 lb 3 M3

Reduced Risk/Organic: Abound (azoxystrobin) 12-15.5 oz 2 11 Pristine (boscalid/pyraclostrobin) 10.5-14.5 oz 4 7/11 RegaliaO (extract of Reynoutria sachalinensis) 2-4 qt --- NC TrilogyO (clarified extract of neem oil) See label 1 NC

Pest Biology: Scouting/Threshold: Cultural: • fruit is susceptible to infection • to prevent spread, treat pre-harvest only if • none up to harvest (causing sunken 4 or more hours of rain or moisture occurs rot in cold storage) frequently • four hours of moisture are • watch leaves and fruit throughout the needed for infection season for lesions

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 121 Apricot Chapter 6: Spray Tables

Apricot Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Spotted wing Conventional: Monitoring in individual drosophila Admire Pro (imidacloprid) - foliar application 2-2.8 oz 3 4 orchards will be important to Malathion 5 EC (malathion) 4 pt 4 1 know if this pest is present. Do (this pest has Sevin 4F (carbaryl) 2-3 qt 4 1 not treat if not found. only been found in a small area of Reduced Risk/Organic: Davis County, UT) Delegate WG (spinetoram) 4.5-7.0 oz 3 5 Success (spinosad) 4-8 oz 2 5

Pest Biology: Scouting/Threshold: Cultural: • first detected in Utah in Davis • adults can be monitored with liquid baits • destroy dropped and over- Co. in 2010 (yeast/sugar water and apple cider vinegar) ripened fruits as these are • adult female has saw-like • only treat if adults are detected or highly attractive to this fly ovipositor and will lay eggs neighboring crops are known to be infested inside ripening fruit

PRE-HARVEST Conventional: Earwigs Sevin 80S & Sevin 4F: make Sevin 4F (carbaryl) 2-3 qt 3 1 applications no more than once Sevin 80S (carbaryl) 2.5-3.75 lb 3 1 every seven days and no more WarriorR (lambda-cyhalothrin) 1.3-2.5 oz 3 3 than three times per crop.

Reduced Risk/Organic: Warrior: 14 day PHI. EntrustO, Success (spinosad) See label 3 5 Apricot

Pest Biology: Scouting/Threshold: Cultural: • adults climb trees and feed on • watch for dark flecks of earwig excrement • band tree at trunk with ripening fruit or holes on fruit sticky adhesive • use corrugated cardboard rolls tied to trunks for monitoring

FALL Conventional: Shothole Copper or Ziram are Bravo Ultrex (chlorothalonil) 2.8-3.8 lb 3 M5 (Coryneum effective. blight) Bravo Weather Stik (chlorothalonil) 3-4 pints 3 M5 Kocide 101 (copper hydroxide) 8-16 lb 3 M1 Ziram 76DF (ziram) 6-8 lb 4 M3

Reduced Risk/Organic: C-O-C-S WDG (copper hydroxide) See label 3 M1 Nordox 75 WGO (cuprous oxide) 5-13 lb 3 M1

Pest Biology: Scouting/Threshold: Cultural: • infects fresh leaf scars in fall • treat at 50% leaf fall for good control and to • none protect overwintering buds

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 122 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Plum

PLUM Pest Phenology Calendar

Stages of Development

Major Calyx Calyx First Full Petal Post Bloom / Summer Post Dormant Pink Green Red Bloom Bloom Fall Harvest Pests June July August Sept.

Cat-facing Adults overwinter on orchard floor or move in from outside Adults, eggs, nymphs inside and outside Insects sources orchard

Coryneum Spores spread to young fruit with splash- Spores infect buds and Blight ing rain twigs

Green Nymphs / winged and wingless adults on Eggs on Eggs on limbs Peach Aphid new growth- move to non-fruit hosts limbs

Iron Apply to soil before foliage emerges; Repeat foliar applications on new growth Chlorosis

Leucostoma Conidia are spread in splashing rain (Cytospora)

Peach Silver Adult females in Adult females in buds Adults, eggs, immatures in buds and on leaves Mite buds Peachtree Adults/ Eggs laid on Lar- Pupae (Crown) Larvae in trunk or under bark, usually below ground trunk/ Larvae bore into vae in in soil Borer trunk trunk Peach Twig Larvae tunnel in shoots; Adults, eggs, larvae in Larvae under Larvae under bark Borer Pupae in bark crevices fruit bark

Powdery Spores spread to fruit and new leaves as Plum Mildew long as new growth present

Apple mildew conidia Rusty Spot infect young adults

San Jose Adults, crawlers, immatures on Immatures on Immatures on limbs Scale limbs, leaves, & fruit limbs

Adults at base Spider Mites Adults at base of tree Eggs, immatures, adults on ground cover and tree leaves of tree

Utah-Colorado Tree Fruit Production Guide 123 Plum Chapter 6: Spray Tables

plum Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments DELAYED DORMANT (Swollen Bud to First Pink) Conventional: Aphid eggs Oil alone is sufficient for R O (Green peach Asana XL (esfenvalerate) + 2% oil 4.8-14.5 oz 2 3 suppression of aphid eggs. aphid, Plum aphid, Mealy plum aphid, Reduced Risk/Organic: Leaf curl plum 2% horticultural oilO See label 2 NC aphid)

Pest Biology: Scouting/Threshold: Cultural: • aphids overwinter as eggs on • if aphid populations were heavy the prior year, • none limbs plan to apply a dormant treatment

Conventional: European red Oil alone is sufficient for mite and Brown Onager (hexythiazox) 12-24 oz 4 10 suppression of both mite mite eggs Savey 50 DF (hexythiazox) 3-6 oz 4 10 species.

(these pests rarely Reduced Risk/Organic: Savey 50 DF: do not make need treatment horticultural oilO See label 4 NC more than one application/ in commercial year. orchards) Pest Biology: Scouting/Threshold: Cultural: • both mite species overwinter as • if mites were severe in the prior season, plan • none eggs on limbs to treat now

Conventional: Lygus and Danitol, Warrior: early Stink bugs Danitol 2.4 EC (fenpropathrin) 10.3-23 oz 3 3 season application of Voliam Flexi (thiamethoxam/chlorantraniliprole) 6-7 oz 3 4/28 pyrethroids can disrupt Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 3/28 beneficial mites. chlorantraniliprole) Plum WarriorR (lambda-cyhalothrin) 2.5-5 oz 4 3

Reduced Risk/Organic: Beleaf 50 SG (flonicamid) 2-2.8 oz 4 9

Pest Biology: Scouting/Threshold: Cultural: • piercing mouthparts cause cat- • control in surrounding crops can keep plant • remove heavy weeds on facing injury to fruits bugs from moving to trees borders and attractive • they overwinter in alfalfa or • use a sweep net to determine population weeds in orchard ground other field crops and migrate density cover to nearby fruit trees when field crops are harvested

Reduced Risk/Organic: Soft scale Centaur: max 2 Centaur WDG (buprofezin) + 2% oil 34.5-46 oz 4 16 applications/season. (this pest rarely 2% horticultural oilO see label 4 NC needs treatment)

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 124 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Plum plum Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments DELAYED DORMANT (Swollen Bud to First Pink) (continued) SOFT SCALE (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as immatures • look for bumps on twigs • none

PETAL FALL Borer Conventional: (Shothole, Voliam XpressR (lambda-cyhalothrin/ 6-12 oz 3 4/28 Flatheaded) chlorantraniliprole) WarriorR (lambda-cyhalothrin) 2.5-5 oz 3 3 (minor pests in Colorado and UT)

Pest Biology: Scouting/Threshold: Cultural: • attack trunks and limbs of trees • treatments only necessary when borer • maintain tree health to under stress populations are known to be high in an prevent infestation • prevent infestations in at-risk area • prune out dead/dying limbs trees (young, stressed, or in • look for sawdust-like frass, loose peeling immediately and remove decline) when adults are active bark, and exit holes debris from spring - mid summer

Reduced Risk/Organic: Western flower Spinosad is toxic to bees O thrips Entrust (spinosad) 1.25-2.5 oz 4 5 for 3 hours after treatment. Success (spinosad) 4-8 oz 4 5 (uncommon on Entrust: adding an adjuvant plum) will improve efficacy. Plum

Pest Biology: Scouting/Threshold: Cultural: • overwinter as adults in • shake flower clusters inside a paper cup or on • none protected areas on the ground dark paper to look for thrips adults; check 5-6 and move to trees during bloom clusters on several trees • feeding on young fruit results in • treat when there is more than 1 adult per russeting cluster

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 125 Plum Chapter 6: Spray Tables

plum Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments SHUCK SPLIT Conventional: Aphids Admire Pro: do not apply (Green peach Admire Pro (imidacloprid) - foliar application 1.4-2.8 oz 4 4 during bloom or when bees aphid, Plum aphid, Admire Pro (imidacloprid) - soil application 7-10.5 oz 4 4 are active. Do not apply Mealy plum aphid, Assail 30 SG (acetamiprid) 2.5-5.3 oz 4 4 more than 10.5 oz/acre per Leaf curl plum Leverage 360R (cyfluthrin/imidacloprid) 2.4-2.8 oz 4 3/4 season for soil application, 14 oz/acre per season for aphid) Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 foliar application. Reduced Risk/Organic: Actara (thiamethoxam) 3-4 oz 4 4 Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN horticultural oilO See label 4 NC M-PedeO (salts of fatty acids) See label 2-3 NC SucraShieldO (sucrose octanoate esters) See label --- NC

Pest Biology: Scouting/Threshold: Cultural: • some species cause severe leaf • check undersides of leaves on terminal twigs • avoid insecticides unless curl, but migrate to an alternate • look for curled leaves necessary to protect host for the summer beneficials

FRUIT PRESENT Conventional: European red Nexter: most effective mite and Brown Envidor 2 SC (spirodiclofen) 16-18 oz 4 23 when applied when mite Onager (hexythiazox) 12-24 oz 4 10 population size is low. Savey 50 DF (hexythiazox) 3-6 oz 4 10 (these pests rarely need treatment Reduced Risk/Organic: in commercial Acramite-50WS (bifenazate) 0.75-1 lb 4 UN orchards) Plum BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC horticultural oilO See label 2-3 NC

Pest Biology: Scouting/Threshold: Cultural: • mites become active in spring, • brown mites occur sporadically in Utah • none and thrive in cool conditions orchards; look for small reddish-brown dots • brown mites feed on leaves at on lower leaf surface or shake branch over night and rest on twigs at day paper

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 126 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Plum plum Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) Conventional: Grasshoppers Dimilin 2L, Orthene Dimilin 2L (diflubenzuron) 2 oz 3 15 97: for non-crop areas Orthene 97R (acephate) 4 oz --- 1 only (borders, fence rows, Sevin 4F (carbaryl) 0.5-1.5 qt 2-3 1 roadsides, etc.)

Semaspore Bait: most Reduced Risk/Organic: effective on nymphs. Do not O Semaspore Bait (Nosema locustae) 1 lb 2-4 --- use if rain within 8 hours.

Sevin: use higher rate for mature grasshoppers. Bait form available.

Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs in the soil, • treat nymphs in spring along roads, ditches, • for more information, see and hatch in spring; nymph to fences, and weedy areas; adults are more Chapter 2, Grasshoppers, adult takes 5 molts difficult to treat pages 13-14.

Conventional: Greater Only lower 12-18” of trunk R Peachtree borer Lorsban-4E (chlorpyrifos) 1.5-4 pt 4 1 should be sprayed. (Crown borer, Voliam XpressR (lambda-cyhalothrin/ 6-12 oz --- 3/28 Trunk borer) chlorantraniliprole) Lorsban-4E: only spray WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3 trunk; do not allow spray on (peachtree borer foliage or fruit. not usually a Mating Disruption (organic): problem on plum) Mating disruption is very Isomate-P 100 4 NC effective and lasts all season. Hang dispensers by early July. Plum Pest Biology: Scouting/Threshold: Cultural: • adults emerge in mid to late • hang pheromone traps in early June to • prevent dense weed June in northern Utah (3-4 determine first moth activity growth around base of weeks earlier in southern Utah) • apply treatments to susceptible trees after trees and continue through Sept moth flight through mid September

Conventional: Leafrollers Dipel: works best when (European, Belt SC (flubendiamide) 3-4 oz 4 28 applied to exposed larvae fruittree, and (1/2 inch in size or less). obliquebanded) Reduced Risk/Organic: Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Altacor: do not make (these pests rarely Delegate WG (spinetoram) 4.5-7 oz 4 5 more than 4 applications per season and do not apply need treatment in O 0.5-2 lb 3 11 Dipel DF (Bacillus thuringiensis sub. kurstaki) more than 9 oz per crop per Colorado or Utah) O Entrust , Success (spinosad) See label 4 5 acre per year. Intrepid 2F (methoxyfenozide) 8-16 oz 4 18

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 127 Plum Chapter 6: Spray Tables

plum Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) LEAFROLLERS (continued) Pest Biology: Scouting/Threshold: Cultural: • overwinter as eggs or • look for rolled leaves with larvae inside • none immatures on limbs; can feed on leaves and fruit, causing scarring

Leucostoma no fungicides are effective for this pest canker (Cytospora) Pest Biology: Scouting/Threshold: Cultural: • cankers develop on trunk and • watch for oozing cankers on scaffold limbs • keep trees growing limbs and start oozing in spring vigorously • stressed, older trees, and trees • prune out dead branches, wounded by winter injury or especially those with borers are most at risk cankers

Conventional: Peach twig One or two sprays needed, borer Assail 30 SG (acetamiprid) 5.3-8.0 oz 3 4 depending on pest pressure. Belt SC (flubendiamide) 3-4 oz 3-4 28 Danitol 2.4 EC (fenpropathrin) 10.6-21.3 oz 2 3 Altacor: max 4 applications Imidan 70-W (phosmet) 4.25 lb 3 1 per season and 9 oz per crop Tourismo (buprofezin/flubendiamide) 10-14 oz --- 16/28 per acre per year. Voliam Flexi (thiamethoxam/chlorantraniliprole) 4-7 oz 4 4/28 Bugitol: apply 96 oz/100 R Voliam Xpress (lambda-cyhalothrin/ 6-12 oz 4 3/28 gal per acre for heavy chlorantraniliprole) infestations. WarriorR (lambda-cyhalothrin) 2.5-5 oz --- 3

Plum Danitol 2.4 EC: do not make more than two Reduced Risk/Organic: applications per season. Altacor (chlorantraniliprole) 3.0-4.5 oz 4 28 Aza-DirectO, Azatin XL (azadirachtin) See label 2 UN Delegate WG: max 4 Bugitol (capsaicin/allyl isothiocyanate) 48 oz/100 g --- NC applications per calendar Delegate WG (spinetoram) 4.5-7.0 oz 3-4 5 year and 29 oz/ac/crop. O 0.5-2.0 lb 2 11 Deliver (Bacillus thuringiensis sub. kurstaki Entrust: do not apply more strain SA-12) than a total of 9 oz per acre EntrustO (spinosad) 1.25-2.5 oz 2-3 5 per crop. Garlic Barrier AG+O (garlic juice) See label --- NC Intrepid 2F (methoxyfenozide) 8-16 oz 2 18 Garlic Barrier AG+: insect repellent. Neemix 4.5O (azadirachtin) 7-16 oz 2 UN Success (spinosad) 4-8 oz 2-3 5 Success: do not apply more than a total of 29 oz per acre Mating Disruption (organic): per crop. Checkmate PTB-XL 200 3-4 NC Isomate-PTB 200 --- NC Tourismo: do not apply more than 3 times per crop season.

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown 128 Utah-Colorado Tree Fruit Production Guide Chapter 6: Spray Tables Plum plum Pest Management Recommendations Rate M (per O Pest Products acre) Eff A Comments FRUIT PRESENT (continued) PEACH TWIG BORER (continued) Pest Biology: Scouting/Threshold: Cultural: • larvae prefer to tunnel into new • time fruit protective sprays at 300-400 • none shoots and tender twigs in first degree-days after first adult moth activity generation

Conventional: Spider mites Nexter: works best when Envidor 2 SC (spirodiclofen) 16-18 oz 4 23 applied before mites reach Onager (hexythiazox) 12-24 oz 3 10 economic threshold. Only Savey 50 DF (hexythiazox) 3-6 oz 4 10 two applications allowed per Vendex 50WPR (fenbutatin-oxide) 1-2 lb 3 12 season.

Savey 50 DF: do not make Reduced Risk/Organic: more than one application Acramite-50WS (bifenazate) 0.75-1 lb 4 UN per year. BiomiteO (Citronellol, Farnesol, Geraniol, Nerolidol) See label --- NC horticultural oilO See label 2-3 NC Vendex 50WP: make no O more than two applications M-Pede (potassium salts of fatty acids) See label 1-2 NC per year. Apply no more than SucraShieldO (sucrose octanoate esters) See label --- NC three lb per acre per year.

Pest Biology: Scouting/Threshold: Cultural: • most likely to become a • look for mite activity on lowest, interior • to protect predatory problem during hot, dry leaves first spider mites, avoid conditions in late summmer insecticides (especially when mites reproduce rapidly pyrethroids) unless necessary Plum

PRE-HARVEST Conventional: Earwigs Sevin 80S & Sevin 4F: Sevin 4F (carbaryl) 2-3 qt 3 1 make applications no more Sevin 80S (carbaryl) 2.5-3.75 lb 3 1 than once every seven days WarriorR (lambda-cyhalothrin) 1.3-2.5 oz 3 3 and no more than three times per crop. Reduced Risk/Organic: Warrior: 14 day PHI. EntrustO, Success (spinosad) See label 3 5

Pest Biology: Scouting/Threshold: Cultural: • adults climb trees and feed on • look for damage where fruit touch, or under • band tree at trunk with ripening fruit leaves; earwigs leave behind black droppings sticky adhesive • they can also be beneficial • tie corrugated cardboard rolls to trunks to predators of other insects monitor

Eff MOA R NC O --- = Efficacy, 4 is most efficacious, and 1 least. = Mode of Action (See pages 50-51 = restricted use pesticide = not classified Information collected from a variety of sources. for descriptions of classes.) = OMRI approved organic pesticide = efficacy unknown Utah-Colorado Tree Fruit Production Guide 129 130 Utah-Colorado Tree Fruit Production Guide Chapter 7: Orchard Floor Management

Chapter 7 Orchard Floor and Weed Management

Orchardists often think of orchard pests as comprising only insects and diseases. Weeds are Several general systems for managing orchard floors, also orchard pests and are equally as capable of listed below, are available and each has advantages reducing yield and fruit quality as insects and and disadvantages to consider before choosing one. diseases. Weeds are pests by competing with trees free strips in the tree row; • Grass alleys between tree rows with vegetation- for water, nutrients, and in extreme cases, light. On

• Solid vegetation cover; the other hand, orchard floor vegetation prevents • Total clear cultivation; soil between rows. erosion on slopes, improves trafficability especially • Mulches in the tree row with vegetation or clear during wet weather, may provide habitat for Grass alleys with vegetation-free strips beneficial insects, and reduces mud. The ability of weeds to compete with fruit trees is well documented. One experiment showed that grass growing near the trunk of apple trees delayed This is the most popular method of orchard floor the onset of fruiting, reduced trunk circumference, management. It has many of the advantages of both solid grass cover and clean cultivation. Usually, her- and reduced shoot growth when compared to trees tion free zone of 2.5 to 3 feet on each side of a row of grown with bare ground surrounding them. Grasses bicides or cultivation are used to establish a vegeta- crop, usually a sod forming grass, is planted and trees, giving a total strip width of 5 to 6 feet. A cover another experiment, adding more nitrogen did not maintained in the alley between the tree rows. This were more competitive than broadleaf weeds. In

overcome the competition imposed by grasses. strip provides an area where roots can grow without to deal with insect and disease pests, an orchard competition from weeds or grass sod. In orchards Just as orchardists develop management plans with a vegetation free zone, most of the root growth occurs in the vegetation free area, especially for floor management plan will help keep weeds plan is best determined before the orchard is young trees. The grass alley provides a solid path for in check. The orchard floor management equipment travel, helps prevent soil erosion, helps maintain soil structure, and aids water infiltration. management should be executed in a timely manner can be minimized and sod establishment can be planted. Management practices for orchard floor Depending on the cover crop sown, weed invasion during the lifetime of the orchard. This chapter fairly quick. Orchard Floor describes some factors to consider while making Solid vegetation cover managed. decisions about how the orchard floor will be Orchard Floor Management Solid vegetation cover, usually grasses, has been Systems used by many growers in the past. It is particularly effective on steep slopes where erosion is a severe problem. It is least competitive in mature orchards planted on large rootstocks (MM.111, MM.106, or jor drawbacks. Vegetation competes with fruit trees seedling). However, solid vegetation cover has ma- the growth of trees and fruit, maintain soil structure, An ideal orchard floor would be easy to maintain, aid reduce erosion, not block the radiation of heat from and results in decreased yields and small fruit size. for water and nutrients which reduces tree vigor the soil on frosty nights, and not compete with trees Vegetation growing right up to tree trunks is also dif

- for water or nutrients. In practice, no single orchard ficult to mow. Mowing equipment can damage trees goals. Current systems balance the ideal against real floor management system accomplishes all of these if operated too close to them. A tuft of vegetation world conditions. for rodents. During the winter when other food is surrounding tree trunks creates a favorable habitat

Utah-Colorado Tree Fruit Production Guide 131 Chapter 7: Orchard Floor Management

scarce rodents will feed on tree trunks up to the can be established with grasses, broadleaf plants such as legumes, or both , although a uniform plant girdle the tree leading to tree death. stand is often easier to manage than one made up of snow line. In severe cases rodents will completely

Clear cultivation itself quickly and thereafter should not require much multiple crop species. A cover crop should establish that competition with trees is minimal. In this system no vegetation remains on the orchard maintenance. It should be chosen and managed so floor. Growers can either use herbicides to kill all vegetation or shallow cultivation. Cultivation may chards. Many different grasses and grass mixtures improve water infiltration of some soils, but fre- Grasses are the most common cover crops in or- quent shallow cultivation damages feeder roots near the soil surface and is energy expensive. Soil erosion are available, so orchardists can choose what is best on all but very flat sites can be increased with bare suited to each particular situation. Several low grow- soil from either cultivation or herbicide use. Bare ing perennial rye grasses are available and allow are wet and may lead to additional soil compaction soil does not provide good traffic support when soils easy orchard access even when headed out. common result. grow additional nitrogen in the orchard. Mowing Legumes can be used as alleyway cover crops to from heavy equipment. Creation of a disking pan is a and discharging the nitrogen rich plant material in Mulch the tree row effectively bands the nitrogen next to Mulches conserve soil moisture and will initially the tree roots. Plant adaptability to the Intermoun- inhibit weed growth around trees. Effective mulches tain West climate greatly influences the legumes that chipped prunings, or shredded newsprint. Mulches shown to produce 50 lbs of nitrogen per acre in an can be considered. Alleyway-grown alfalfa has been include straw, sawdust or shavings, hay, leaves, orchard system. A drawback to this type of system is

are expensive to obtain and apply on an annual or for long periods, especially perennial weeds. Or biennial basis. They do not control weeds effectively the lack of control over the timing of nitrogen avail- ganic mulches may bring additional weed seeds into - ability. If the nitrogen becomes available late in the the orchard—and may bring in new weed species. that would delay hardening off of the orchard tree season, then this could create a flush of shoot growth As they decompose, some organic mulch materials and increase susceptibility to early winter injury. Considerations on the time of mowing could appro priately add the nitrogen according to tree needs, tie up available soil nitrogen. - bonded polyester fabric mulches has added an addi Development of synthetic plastic film and spun and limit potential negative effects. Floor Orchard Orchard - tional management option. However, these products Use of legume covers does come with a few dis- photodegredation of the material. These products must be covered with an organic mulch to prevent advantages. Stink bugs and lygus can feed on the are typically applied to the soil and the trees are legumes, and after mowing, could move to the trees planted into the weed barrier. gumes also require more irrigation than some other and feed on fruits, causing cat-facing injury. Le-

Cover Crops cover crops. In an established orchard environ- to transpire more than twice as much water as a ment, alfalfa and alfalfa-clover mixes were shown

conventional grass alleyway. Although legumes add not outweigh the cost of managing increased pest Cover crops can be one component of orchard floor nitrogen to the orchard soil, the fertility benefits may crops are important in maintaining soil structure, populations or maintaining proper soil moisture management, but are not a “system” alone. Cover where irrigation water is limiting. ducing mud and dust, and maintaining an acceptable encouraging water infiltration, reducing erosion, re-

driving surface for equipment. A good cover crop

132 Utah-Colorado Tree Fruit Production Guide Chapter 7: Orchard Floor Management

Cover crop establishment again when seed heads have formed on grasses but begin at the same time as preparation for orchard seed, less growth will occur after mowing. Mowing Preparation for cover crop establishment should before the seed has matured. Once grasses have set establishment. Perennial weeds such as thistles and

just before harvest will facilitate moving shakers, aggressive bunch grasses should be controlled with bins, ladders, and boxes through the orchard. If the soil tested and apply any phosphorus or potas non-residual herbicides such as glyphosate. Have much regrowth occurs after harvest, the orchard sium fertilizer as indicated in the soil test. - should be mowed again in the late fall to remove habitat favorable for rodents. Grasses can be planted in either the spring or late summer (August 15 to September 15). Late summer Drought tolerance is another good measure of a cov- establishment is preferred because the soil is warm be low. Perennial grasses can go dormant in the er crop. Irrigation required for cover crops should which results in rapid germination and because summer when irrigation is sporadic, but will regrow annual weeds that will germinate at the same time

in the fall with cooler and wet weather. However, irrigation is still required. should be killed by fall frosts before they flower and in arid areas like the Intermountain West, periodic in the fall before tree planting. Once the sod is produce seed. Establish sod over the entire orchard growing well, mark out the orchard rows and kill the grass in the planting row using glyphosate or para Rodent Management

- the winter and spring. With sod already in place, quat. The dead sod will help prevent erosion during planting will be easier and less muddy. Rodents, primarily voles, can significantly damage Legumes are best planted in the spring after the soil orchard trees. In the winter when other food is scarce, voles will gnaw the bark from trees up to the completely girdled in just one winter. Managing the snow line. In severe cases hundreds of trees can be has warmed and can be worked. Usually a grass/ both types of plants. legume mixture is planted to obtain the benefits of orchard floor to reduce habitat is a critical part of Cover crop maintenance keeping vole populations below action thresholds.

Utah is host to both meadow voles (northwestern nance should be minimal. Maintenance operations species are also widespread in western Colorado Once a cover crop is established, required mainte- Utah) and pine voles (throughout the state). Both include fertilizing, mowing, irrigating, and control Orchard Floor ling weeds. No nitrogen fertilizer beyond that pro Litters contain up to 12 pups and females can re - orchard areas. Voles rarely live for more than 1 year. - - vided for the trees should be required, especially if a produce in any season. Females reach reproductive grass/legume mixture is used because legumes can maturity in 3 weeks and a fecund female can have capture atmospheric nitrogen and make it available about four litters per year. Under favorable condi- to grasses (or other non-legume vegetation). tions, vole populations can increase rapidly.

Grass covers will require mowing several times each An effective vole management plan in orchards con- year. A mowing height of 3-4 inches is best. If dan- sists of five components: with tree fruits, the dandelions should be mowed delions or other weeds are flowering concurrently • Habitat destruction • Scarce food supply to remove the flowers. Weed flowers compete with • Exclusion fruit tree blossoms for bee visits and poor pollina- • Facilitating predators also the critical time for frost protection. A closely tion may result. The flowering period of spring is • Baiting with rodenticide

mowed orchard floor can radiate more energy back into the orchard than one with tall vegetation. Mow

Utah-Colorado Tree Fruit Production Guide 133 Chapter 7: Orchard Floor Management

Habitat destruction Facilitating predators

ments and from predators. Vegetation in orchards gophers. The kestrel is a small hawk that is an excel Like all mammals, voles require shelter from the ele- Birds of prey are important predators of voles and - will return to maintained boxes year after year, and nearby fence rows or brush piles provide ad- lent predator for mouse and vole control. Kestrels ing habitat is to mow the orchard close. The last but are highly territorial. The barn owl (found in equate habitat. The most efficient means of destroy-

mowing in the fall should cut remaining vegetation limited numbers in Utah), because of its voracious short. Orchards that are clear cultivated sometimes appetite for gophers, voles, and mice, is a valuable leave tufts of vegetation around each tree. This is friend to the orchardist. During a 4-month nesting in the winter. Chipping or burning brush piles prime vole habitat and may encourage trunk girdling season, a family may consume about 120 voles or reduces habitat. Keeping fence rows clear also re in the West is dwindling due to lack of nesting sites, 10-12 gophers per night. The barn owl population which orchard growers can do something about by - moves rodent habitat. Equipment “bone yards” can measures are taken to attract predator birds. also provide shelter for rodents. Leaving no place to providing boxes. Avoid the use of rodenticides when hide will reduce vole populations. as habitat must be weighed against their desirable Kestrels Mulches can also be vole habitat and their potential To attract birds of prey: characteristics such as moisture retention and weed • : Screw nesting boxes to power poles or emergence. trees 10-20 feet above ground, away from human chances of nesting, but note that a pair may activity. Install up to 1 per 5 acres to increase Scarce food supply defend up to 250 acres. Adding a bit of nesting

diet is high energy content foods such as green tis Voles feed on a variety of materials. Their preferred material (twigs, wood shavings) can help attract sues, seeds, nuts, and fruit. When preferred foods starling nests. Clean boxes each year. - the birds. Monitor each box weekly and remove are absent, they will eat woody materials and bark. Barn owls keep old wooden barns; they will not nest in • : To attract/keep birds on the farm, Fruit that falls to the ground as part of the harvest With adequate food, populations can skyrocket in posts facing east and away from roads or busy process provides voles with their preferred diet. metal barns. Nest boxes on trees or 8-ft steel the fall. Flail chopping dropped apples will cause trees or abandoned buildings. A tall tree within orchard activities can be used in place of cavity rodents. them to decompose faster and provides less food for 50 yards of the nest box is necessary to provide Floor ing site. The boxes must be cleaned yearly and Orchard Orchard Exclusion cover. Owls may patrol up to 200 acres per nest- kept free of starlings. chard blocks, but it is possible to exclude access to Other large raptors It is not possible to exclude voles from entire or- owls and raptors to spot their prey. Retain old • : Perches are necessary for the trunks of individual trees. Trunk guards will help protect trunks against vole feeding. Various trees in edge plantings or install posts with a 2x4 across the top to facilitate hunting activities. commercial products are widely available. An inex- Baiting with rodenticides pensive trunk guard can be made using ¼ inch mesh and make a cylinder around the trunk and fasten the galvanized hardware cloth. Cut an 18 inch square been instituted, baiting may be necessary if popula Once the previous four management practices have into the soil to discourage burrowing under the tions are still high—especially in the fall. Population two edges with wire. Place the cylinder 2-3 inches - guard. action thresholds are determined by placing 50 to 100 apple slices in a block of trees. Slices should be

shingle or small plank supported by a stone. After placed under some sort of cover such as a wooden

134 Utah-Colorado Tree Fruit Production Guide Chapter 7: Orchard Floor Management

typically selects for perennial weeds and has a high ber of slices that are missing or that show feeding. er risk of damaging tree trunks and shallow roots. 24 hours return to the orchard and count the num- - When 20% to 25% of slices are missing or show Chemical weed management exposes applicators,

and further action is warranted. feeding, the potential exists for serious vole damage fruit trees, and the environment to toxic materials.

The advent of chemical weed killers (herbicides) Rodenticides fall into two groups: Anticoagulants has given fruit growers many choices for controlling and zinc phosphide. Both products are registered in orchard weeds. Herbicides have various modes of Utah, but only zinc phosphide is registered in Colo- action, but can conveniently be grouped as either rado. Both are broadly toxic to mammals and must pre-emergent or post-emergent herbicides. Pre- be handled with great care. Both products come in emergent herbicides are active in the soil against and wax pellets. Zinc phosphide kills quickly while various formulations such as treated cracked corn germinating seedlings. Post-emergent herbicides anticoagulants kill more slowly and may engender are active against vegetation that is already up and growing. Post-emergent herbicides can further be widely used rodenticide. bait shyness. Anti-coagulants are still the more categorized as contact (paraquat) or systemic. Post- emergent systemic herbicides can also be divided as selective (2,4-D) or non-selective (glyphosate). Effective baiting requires presenting the bait in a set- ting so rodents will feed and so non-target animals Effective chemical orchard weed control programs cides. When the initial spring herbicide application don’t have access to the bait. An inexpensive bait utilize both pre-emergent and post-emergent herbi- station is made using PVC pipe and tees. Use 1½ or and push a piece of pipe into each opening of the 2 inch PVC pipe. Cut the pipe into 4-5 inch segments includes both a pre-emergent and post-emergent tee. Place the bait stations in the orchard unbaited germinated is controlled and the new weeds are material the spring flush of weeds that have already for a week or two to allow habituation. To place the bait, lift up the sidearm of the tee and place a small second herbicide application is required later in the kept from growing—providing longer control. If a Voles are likely to feed on bait when they can see all cient. Check the product labels for allowable tank quantity of bait in the tee, then lay it back down flat. season, a post-emergent product usually is suffi- mix combinations. to “back out” of the pipe. The openings are small the way through the tube and when they don’t have

the bait is protected from moisture. tions. Herbicide application must be made with a Orchard

enough to keep non-target animals from the bait and Herbicides are active at relatively low concentra- Floor well maintained and accurately calibrated sprayer. When using rodenticides read and follow the label directions. Store them in a dry place where other Fixed boom applicators with flat fan or low-drift nozzles at low pressures (15-25 psi) are best for otherwise. Low pressure application reduces the animals and children do not have access. Wear ap- herbicide application—unless the label specifies propriate personal protective equipment (especially prone to drift. rubber gloves) to protect yourself. number of very small droplets. Small droplets are Weed Control in Orchards newly planted and young trees. Ensure the soil has Use extreme caution when applying herbicides to

As orchard tree density increases the importance completely settled before applying pre-emergent absorbed through the tender bark of young trees herbicides. Post-emergent herbicides can be increases. Weeds may be managed either mechani resulting in tree damage or death. Some product of controlling competing vegetation (weeds) also labels restrict application to newly planted trees. - Carefully read the label before application. cally or chemically. Each approach has advantages and disadvantages. Mechanical weed control usually requires more energy, is short lived, non-selective, Utah-Colorado Tree Fruit Production Guide 135 Chapter 7: Orchard Floor Management

If an herbicide is being used for the first time, treat a • Use herbicide sprayers only for herbicides. small area of the orchard first to gain experience and • Clean sprayers thoroughly following use—espe- to check for effectiveness. Rotate the herbicides used among herbicide classes. cially following 2,4-D. Rotating herbicides reduces “weed shifting” where • Dispose of excess spray material properly. Avoid weeds that are tolerant to the materials being used contact with non-target vegetation. • Do not graze a treated orchard’ can thrive. This is particularly important for pre- dance with label requirements. cide with a different mode of action. For example, • Store herbicides in a secure location in accor- emergent herbicides. Be sure to rotate to an herbi- pump, lines, and nozzles should be thoroughly • Zinc sulfate is highly corrosive. The spray tank, simazine and diuron have the same mode of action, desired result. so alternating these products would not have the rinsed and flushed after using. • Foliar application during or followed by damp eties of stone fruits. Herbicide use best practices: weather may result in spray injury on some vari- • Use an accurately calibrated fixed boom sprayer, flat fan or low drift nozzles, low pressure and constant speed (http://utahpests.usu.edu/ipm/ References htm/pesticides). • Read the full herbicide label before making an Pacific Northwest Weed Handbook. 2011. http:// tors must follow the label for the product you are application. Labels change over time and applica- pnwhandbooks.org/weed/ using.

West, B.C. and T.A. Messmer. 2010. Voles. Utah State • Wear the personal protective equipment speci- University Cooperative Extension publication NR fied on the label for the product(s) being used. WD 009. 4pp. Floor Orchard Orchard

136 Utah-Colorado Tree Fruit Production Guide Chapter 7: Orchard Floor Management

Herbicides labeled for use in Utah and Colorado

Formulation Name Crop Weeds Treated (active ingredient) Remarks Pre-emergent

Apple, pear, cherry annual and perennial grasses Casoron 4G Apply Nov. to March when soil temp is and broadleaves (dichlobenil) below 45˚ F. Rain/irrigation is needed for activation; shallow incorporation recommended.

ALL annual broadleaves and Chateau WDG Limited to 24 oz per year. Moisture is suppression of grasses (flumioxazin) necessary to activate pre-emergence applications. Apple: apply only between harvest and pink stage. Stone fruit and pear: apply only between harvest and bud break.

ALL annual grasses and Devrinol 50DF Apply late fall to early spring. Moisture broadleaves (napropamide) needed within 24 hours of application. Maximum 1 application/year.

ALL annual broadleaves and Goal 2XL Do not apply between bud swell and suppression of grasses (oxyfluorfen) harvest.

Apple, pear, peach annual grasses and Karmex DF Do not treat trees grafted on full dwarf broadleaves (diuron) rootstocks. Maximum 1 application/year.

ALL annual and perennial grasses Kerb 50-WR Apply as post-harvest application when and listed broadleaves (pronamide) temperatures are below 55˚ F. Rain or irrigation required to activate. Maximum 1 application/year.

ALL annual grasses and Matrix FNV Weeds are controlled 60-90 days after broadleaves (rimsulfuron) application. If weeds are present at application, a labeled burn down herbicide such as glyphosate, or paraquat, will improve control. Do not use in mix water above Orchard

8.0 pH. Best results when soil is moist at Floor the time of application and 0.5 inch rainfall occurs within 2 weeks of treatment.

Apple, pear, tart annual grasses and Princep 4L One application per year. Do not apply to cherry broadleaves (simazine) gravelly or sandy soil.

Apple, peach annual grasses and Sinbar 80 WP Maximum rate is 1 lb per year. broadleaves (terbacil)

ALL annual grasses and Solicam DF* Apply from fall to early spring. Rainfall broadleaves (norflurazon) or irrigation of 0.5 inch is necessary for activation.

ALL annual grasses and listed Surflan AS Rainfall or irrigation to 0.5 inch required for broadleaves (oryzalin) activation.

R = restricted use pesticide *=not for use on stone fruits on western slope in Colorado

Utah-Colorado Tree Fruit Production Guide 137 Chapter 7: Orchard Floor Management

Herbicide Sprays, continued

Formulation Name Crop Weeds Treated (active ingredient) Remarks Post-Emergent ALL annual broadleaves; green Aim EC Use anytime of the season, always with suckers (carfentrazone) surfactant. Mix with glyphosate or paraquat for better control. ALL annual and some perennial Amine 4, Do not apply during bloom or near irriga- broadleaves Saber, others tion times. Do not apply to bare ground. (2,4-D amine) Maximum 2 applications per year and 75 days between applications. ALL annual broadleaves and Chateau WDG Apple: apply only between harvest and suppression of grasses (flumioxazin) pink stage. Stone fruit and pear: apply only between harvest and bud break. Limited to 24 oz per year. Use with an adjuvant. Stone fruits listed annual and perennial Fusilade DX Always add non-ionic surfactant. Rainfast in grasses (fluazifop-P) 1 hour. ALL annuals and some perennial glyphosate Rate depends on weed species and stage of grasses and broadleaves growth. Does not provide residual control; can be mixed with labeled pre-emergence herbicides. Avoid contact with all tree parts. ALL most annual grasses and Gramoxone SLR Repeat applications are necessary for broadleaves and top kill of (paraquat) sustained control. Always add non-ionic perennial weeds surfactant. Maximum 5 applications/year. Pome fruits, peach annual grasses and Karmex DF Pome fruits: apply March – May only. broadleaves (diuron) Do not treat trees grafted on full dwarf rootstocks. Maximum 1 application/year. ALL but plum annual and perennial grasses Poast Use with 1.25% oil. Do not mix with other (plum is non-bearing (sethoxydim) herbicides. Do not apply within 1 hour of application only) rainfall. Will not work on drought-stressed grasses. ALL annual and perennial grasses Scythe 4.2E BIO Contact non-selective burn down control

Floor and broadleaves (pelargonic acid) of a variety of weeds. Can be mixed with Orchard Orchard glyphosate. Stone fruits perennial broadleaves Stinger Apply while weeds are generally small and (clopyralid) actively growing. Do not exceed 2/3 pt/ac/ year. Highly leachable in light soils. ALL annual grasses and listed Surflan Mix with glyphosate or paraquat. Rainfall or broadleaves (oryzalin) irrigation to 0.5 inch required for activation. ALL annual and perennial Venue Use from post-harvest to pre-bloom broadleaves (pyrafluven ethyl) only. Contact herbicide. More effective on weeds less than 4 inches tall. Do not make more than 3 applications/year. Mixing with glyphosate or paraquat improves effectiveness. Spray water must be less than 7.5 pH.

R = restricted use pesticide BIO

= EPA-listed biopesticide

138 Utah-Colorado Tree Fruit Production Guide Chapter 7: Orchard Floor Management

Herbicide Sprays, continued

Formulation Name Crop Weeds Treated (active ingredient) Remarks Non-Bearing ALL annual broadleaves and Chateau WDG Do not apply to trees established less than suppression of grasses (flumioxazin) one year, unless protected with non-porous wraps.

ALL listed annual and perennial Fusilade DX Always add non-ionic surfactant. Rainfast in grasses (fluazifop-P) 1 hour.

ALL listed broadleaves Gallery 75 Pre-emergence only. Only apply to settled (isoxaben) soil with no cracks. Rainfall or irrigation of 0.5 inch required within 21 days of application.

ALL annual and perennial grasses Poast Use with 1.25% oil. Do not mix with other (sethoxydim) herbicides. Do not apply within 1 hour of rainfall. Will not work on drought-stressed grasses. Peach, nectarine, and plum are very tolerant of Poast and it may be applied over the top of non-bearing trees.

ALL annual grasses and listed Prowl 3.3 EC Pre-emergence herbicide. Use before bud broadleaves (pendimethalin) swell. Rain or irrigation required within 21 days of application.

ALL annual grasses and Reglone Post-emergence herbicide. Complete broadleaves (diquat) coverage essential.

ALL most annual and perennial Select 2EC Post-emergence herbicide. Mix with non- grasses (clethodim) ionic surfactant (not oil). Rainfast in 1 hour.

Stone fruits annual grasses and Showcase Pre-emergence, dormant applications only. broadleaves (triflualin+isoxaben +oxyfluoren) Orchard Apple, apricot, annual grasses and Sinbar For non-bearing, newly-planted trees, make Floor cherry, peach, pear, broadleaves (terbacil) the first application after a significant rainfall plum or irrigation that will settle the soil around the base of the tree.

ALL annual grasses and listed Snapshot 2.5 TG Pre-emergence herbicide; 0.5 inch rain broadleaves (isoxaben+trifluralin) or irrigation required within 3 days of application.

ALL annual and perennial Venue Do not allow spray to contact green bark broadleaves (pyrefluven ethyl) of trunk area. Contact herbicide. More effective on weeds less than 4 inches tall. Do not make more than 3 applications/ year. Mixing with glyphosate or paraquat improves effectiveness. Spray water must be less than 7.5 pH.

Utah-Colorado Tree Fruit Production Guide 139 140 Utah-Colorado Tree Fruit Production Guide Chapter 8: Growth Regulation and Thinning

Chapter 8 Plant Growth Regulators and Thinning

Plant growth regulators (PGRs) can be used with buds, young leaves, and developing seeds. In addi some precision for controlling bloom, thinning fruit, tion to being used as plant growth regulators, auxins - regulating growth, and adjusting harvest season of orchard crops. PGRs are absorbed by plant cells, can also be herbicides (2,4-D and other phenoxy primarily through the leaves and fruit, where they synthetic auxins that can be used to thin fruit, to in herbicides). In apple production, NAA and NAD are interact with the biochemical “machinery” of the hibit water sprout and sucker growth, and to prevent - plant. They work by mimicking naturally occurring plant hormones, or by blocking the production or an auxin, has a similar chemical structure. pre-harvest fruit drop. Carbaryl, while not strictly activity of natural plant hormones. Gibberellins This publication provides information on which Gibberellins also promote growth. They are pro duced in very young leaves, developing seeds, fruit, - and gives instructions on how, when, where, and and roots. Gibberellins cause cell elongation, includ plant growth regulators to use for a specific effect in what quantities to apply them. Because plant ing shoot growth, and are involved in regulation of response can vary greatly due to a range of factors, - it is important to keep detailed records of use and used to improve fruit size and to prevent russeting. dormancy. Commercially, gibberellins have been Several growth retardants, including Apogee, limit your orchard. biosynthesis of gibberellins and thus inhibit shoot plant response to help you fine-tune applications for growth. Naturally Occurring Plant Hormones Cytokinins

Cytokinins promote cell division. They are thought kinins are involved in apical dominance, branching, substance that is produced in one part of a plant to be produced in the roots and by young fruit. Cyto- A plant hormone is commonly defined as an organic and stimulating bud initiation. Benzyladenine is a and translocated to another part where, at very synthetic cytokinin used for fruit thinning (Maxcel). low concentrations, it stimulates a physiological response. Plant hormones may promote or inhibit Abscisic Acid Abscisic acid (ABA) is a growth inhibitor. It controls involved, the concentration, the time, and the plant growth, depending on the specific hormone the dormancy of buds and seeds and inhibits shoot part it is acting on. Plant hormones occur naturally. growth. Exactly how ABA works is not well under When they’re synthesized chemically they’re known stood. It may act directly by blocking synthesis of Thinning as plant growth regulators or PGRs. Some PGRs act - PGR enzymes, or it may operate indirectly by blocking by blocking either the synthesis or the activity of RNA synthesis, thus blocking the formation of en plant hormones. zymes that in turn form the growth promoters. ABA - is produced in mature leaves, along with many other plant tissues. It is not currently used as a PGR in compounds: auxins, gibberellins, cytokinins, ab Plant hormones can be grouped into five classes of tree fruits but is available for promoting fruit color scisic acid, and ethylene, each of which is described - development in table grapes.

Auxinsbriefly below. Ethylene This is the only known gaseous plant hormone. Many plant organs synthesize ethylene, and it moves that contribute to the elongation of shoots, but These are primarily growth-promoting substances readily in the air surrounding the tree. Usually, eth at high concentrations they can inhibit growth of ylene has an inhibitory effect on plants. It promotes lateral buds. Auxins are generally produced in apical -

Utah-Colorado Tree Fruit Production Guide 141 Chapter 8: Growth Regulation and Thinning

abscission of leaves and fruits, inhibits shoot elonga gen, or plant or leaf injury also increase sensitivity. tion and favors caliper development, and, along - with auxin, inhibits lateral bud development. On for trees that are stressed. Although damaged foli Doses should be decreased or application eliminated the other hand, it can break dormancy in buds and age can reduce absorption, weak trees can still be - seeds and causes rapid ripening of apples. In apples, oversensitive to PGR applications. ethylene is involved in the transition of fruit from being physiologically mature to ripe. Once exposed Dosage to ethylene, their storage life is shortened. Ethephon is a synthetic compound that releases ethylene upon fungicides) PGRs have a relatively narrow acceptable Compared to crop protectants (insecticides and application. ReTain interferes with ethylene bio dose range, where overdose can result in nega synthesis, allowing fruit to hang on trees longer and - - low, none of the desired response will be achieved. tive side effects. Conversely, when the dose is too or SmartFresh) blocks the receptor for ethylene, pre Therefore, PGRs are applied in very precise and low lengthens storage life. 1-Methylcyclopropene (1-MCP concentrations. Extreme care must be taken to mix - and apply these chemicals accurately to avoid incor venting ethylene action. Since 1-MCP is a gas, it has but has not been used commercially in the orchard. rect dosage. PGRs should be applied as dilute high been used to slow post-harvest ripening in storage, - volume sprays (200 + gallons per acre) to ensure Factors Affecting Plant Response uniform coverage and because applying the correct

The effectiveness of a PGR application is determined dose is more difficult in low-volume sprays. Grow- by (1) how much of the active ingredient is absorbed should use the highest volume possible. ers that only have access to low-volume sprays by the plant and reaches the appropriate tissue or cells, and (2) how sensitive the plant is to the Spray Tank Considerations PGR. Environmental conditions at the time of Surfactants are a class of spray tank additives that application, formulation of the material, and method affect the surface tension properties of the spray of application all affect plant absorption. Tree age, solution, which increases leaf wetting in order to tree vigor, dosage, timing and cultivar all interact increase absorption. Read the PGR product label to affect plant sensitivity. By understanding the carefully before including a surfactant. Many of the role of each of these variables, you will be better commercial PGRs come formulated with surfactants equipped to adjust PGR applications, within product to provide the proper solution characteristics for leaf wetting. Adding more surfactant to the spray tank solution may not appreciably improve PGR delivery, label allowances, to compensate for year-to-year and and may actually decrease retention of the spray block-to-block variation. Environmental Conditions solution on the surface of the plant. Weather conditions before, during, and after applica tions affect response to PGRs. High temperatures, Many of the PGRs are sensitive to spray solution pH, - PGR slow drying conditions, and healthy foliage will en where the stability and activity of the PGR molecules Thinning are best in slightly acidic solution. With the alkaline - temperatures, fast drying conditions, and damaged water typical of orchards in the Intermountain West, hance absorption and increase plant response. Cool trees or foliage will decrease plant response. Be a spray tank buffer will improve both the stability cause of low humidity and high temperatures typical and uptake of the PGR. PGRs should not be tank - mixed with pesticides. are typically best, to allow for proper drying time of Utah weather, evening or night-time applications Timing PGRs. PGRs can cause different effects when applied at and avoid volatilization and photo-degradation of different times during the season. For a predictable Tree Vigor and Age response to occur, PGRs must be applied in a rela Weak trees and young trees are more responsive to tively narrow time period, usually within a few days. - PGRs. Stresses caused by lack of water, low nitro

- 142 Utah-Colorado Tree Fruit Production Guide Chapter 8: Growth Regulation and Thinning

Cultivar Fruit size is determined by the total cell number per fruit. In apples, cell division ceases by about 30 days sponsiveness to PGR application. This is especially Different cultivars display varying degrees of re- true for chemical thinning. after full bloom. Therefore, final fruit size is influ- enced greatly within the first month after bloom. Evaluating and Monitoring Plant Likewise, initiation of apple flower buds also occurs both fruit size and return bloom, excess fruit must Response within the first month after bloom. To optimize preferentially removes small, weak fruit. be removed during this period. Chemical thinning To evaluate the effectiveness of PGR treatments, Determining Crop Load leave some trees untreated for comparison. Keep The following questions will help you evaluate ing detailed accurate records of application rates, whether your crop needs to be thinned. Remember, - weather, and plant response will help in making ad it’s better to be conservative when applying thinning justments during future years to achieve the optimal materials. It’s possible to take more fruit off but not - response. to put fruit back on.

Effect of Sunlight on Thinning How many seeds are present? When fruitlets are Agents • 3-5 mm, cut open a few and count the seeds. likely to drop naturally and will be easier to thin While the precise mode of action of PGR thinning Fruitlets with fewer than five seeds are more than fruitlets with more seeds. agents is not clearly understood, evidence is ac cumulating that the carbohydrate status of the tree What color are the seeds? Tan or brown seed - color at this time of the season indicates that the • status is affected by light levels (more light = more seeds are not viable, whereas viable seeds will plays a key role in plant sensitivity. Carbohydrate photosynthesis = improved carbohydrate levels) and be white to yellow. Fruitlets with fewer viable by overall tree health. This effect occurs both at the seeds are more likely to drop naturally, and are also more sensitive to chemical thinners. In cast conditions and internal shading both make the some varieties, the color of the pedicel (stem) whole-tree and the individual-branch level. Over- fruit more sensitive to PGR thinning applications. is also an early indicator of whether or not the fruitlets will persist beyond June drop. Red color in the pedicel indicates that the fruitlet Likewise, well-exposed branches under full sunlight will likely not persist. Tconditionshinning tendApple to be Fruitmore difficult to thin. Are there too many apples on the tree? If fruit Thinning PGR • if there are more than two fruitlets developing clusters are within 6-8 inches of each other and in each cluster, there are too many apples on the than are needed to produce a full crop of marketable Apple trees typically produce more flowers and fruit tree. fruit. Many of the excess fruitlets will drop shortly after petal fall or later, during June drop. In a good What was the crop load like last year? Trees will crop year, the remaining crop load will still be too thin more easily in the year following a heavy • large for the individual fruit to develop adequate crop. size. Also, heavy crop loads inhibit the ability of the tree to develop blossom buds for the following year, What was bee activity like in the orchard? Were resulting in biennial bearing. Thinning the crop pollination conditions good or less than ideal. • will maximize fruit size and quality, and allow for Remember that bees don’t like to work in foul weather any more than you do.

adequate flower bud initiation.

Utah-Colorado Tree Fruit Production Guide 143 Chapter 8: Growth Regulation and Thinning

Available Products Naphthalene acetic acid (NAA) There are currently four materials available for fruit NAA is a synthetic auxin growth regulator and is rec thinning: carbaryl (Sevin), benzyladenine (Maxcel), ommended for cultivars that mature after September - naphthalene acetic acid (NAA), and Naphthalene 1. Fruit thinned with NAA do not show as strong of a positive size response as those thinned with carbaryl pend on the cultivar, the condition of the trees, and or BA. acetamide (NAD). The best material to use will de- time of application.

Carbaryl (Sevin) mm in diameter. Since fruit diameter tends to vary NAA should be used when the king fruit are 8 to 12 with time of day, measure the fruit at the same time Trees thinned with carbaryl will have larger fruit each day beginning at petal fall to determine opti Carbaryl a very effective thinning agent for apples. - carbaryl is an insecticide that is toxic to bees, and to for most fall to winter cultivars. NAA is a very active, mum timing. Apply NAA at a rate of 10 to 15 ppm than those thinned with NAD or NAA. However, potent material and should be used with caution.

beneficial insects. To minimize danger to these es- use the lowest possible rate, spray only after dark for fruit thinning: sential beneficial insects, use the “XLR” formulation, Consider the following factors before applying NAA and after petal fall when bees are not active in the orchard. to NAA. • Weak trees and young trees are more sensitive

petal fall, after the crop load has been determined. Carbaryl should be applied within 28 days after • Shaded limbs tend to over thin. If the weather has been cool, delay application until • For best results, apply when temperatures are Apply ¼ to ½ lb of carbaryl per 100 gallons of water. between 70° and 75°F. the central “King” fruit are 10 to 15 mm in diameter. tion will increase uptake and thinning action. tank mix. • Light rain or dew within a few hours of applica- For increased thinning action, add NAA or NAD as a of NAA and carbaryl will increase thinning. For Benzyladenine (BA or Maxcel) • For some hard-to-thin cultivars, a combination this combination, the concentration of NAA are natural plant hormones involved in regulating should be decreased by half. Benzyladenin is a synthetic cytokinin. Cytokinins cell division. The effect of BA is to increase fruit size beyond that expected by reducing fruit number. It such as Maxcel or Promalin. Studies with Red • NAA should not be combined with other PGRs

should be applied when king fruitlets are 5 to 10 of NAA and either Maxcel or Promalin within the conditions, this typically occurs within 7 to 21 days Delicious in Michigan indicated that applications mm in diameter. Depending on cultivar and weather same season resulted in excessive “pygmy” fruit. after full bloom. PGR

Thinning Naphthalene acetamide (NAD)

maximize drying time. High temperatures within is best for summer apples that mature before Sep Apply a dilute spray of 75 to 200 ppm at night to NAD is another synthetic auxin growth regulator. It - sponse. BA is most effective when air temperatures 8 hours of application will increase the thinning re- tember 1. Apply NAD between late bloom and petal fall (4-8 days after full bloom). Applications after are between 70°F and 75°F. petal fall can result in poor thinning. NAD is applied BA can be tank mixed with carbaryl to improve the at a rate of 35 to 50 ppm for most summer cultivars. excessive pygmy fruit. Do not use NAD on Red Delicious as it can cause thinning action. Usually ¼ lb of carbaryl is sufficient.

Do not tank mix with other pesticides.

144 Utah-Colorado Tree Fruit Production Guide Chapter 8: Growth Regulation and Thinning

Thinning Stone Fruit Controlling Apple Tree Vigor

Unfortunately, PGR formulations are not available for There are many reasons for controlling an apple tree’s vegetative vigor. Overly vigorous trees take and cherries. Application of some mildly caustic longer to prune and have more internal shading post-bloom thinning of stone fruits such as peaches materials during full to late bloom has been used successfully in the past to reduce fruit set in both more sprays and are harder to cover adequately that reduces fruit coloring. Dense canopies require apples and stone fruits. The mode of action is to al with pesticides. Trees planted too close together on low pollination to occur on early blossoms and then overly vigorous rootstocks may also be a problem. - damage the later blossoms with the caustic material, Overly vigorous trees produce more succulent shoot preventing further pollination. Blossom thinning growth. These succulent shoots are more suscep

- areas of the Intermountain West is extremely risky. with these caustic materials in cold and frost-prone tible to fire blight infection. Recent trials in Utah indicated that application of Prohexadione-Calcium (Apogee) caustic bloom thinners to peaches, followed by cold Apogee is a PGR that interferes with the production of gibberellins in the plant. Gibberellins are plant crop loss. hormones involved in shoot elongation. Inhibiting but non-freezing temperatures, resulted in complete gibberellin production decreases shoot growth. The Bud Thinning effect of a single application of Apogee lasts only 2 Application of gibberellins (GA3, ProGibb) can be to 3 weeks, depending on the inherent vigor of the tree and the time of the season. Once Apogee has buds formed for the following season. This has been applied to an orchard block, repeat applica used in stone fruits to reduce the number of flower - weak tart cherry trees, to delay fruiting in young tart the season of maximum shoot growth has passed. been used successfully to prevent over-cropping of tions at 2-week intervals are typically required until cherry orchards, and to “thin” processing peaches When a repeat application is missed, there may be a where hand thinning and detailed pruning are not “rebound” period when shoot growth resumes at a rate that appears to exceed that of untreated trees.

justified by the value of the crop. As older tart cherry trees begin to decline, the natural tendency is for these trees to produce too A beneficial effect of Apogee is that trees are less infections does not appear to be affected, the rate at susceptible to fire blight. While the number of which the infections spread is reduced so that prun many flower buds. If fruit are produced at lower in Montmorency), blind wood results because there nodes on one-year-old wood (which happens often - are no vegetative buds to produce spurs or branches. becomes more practical. ing out fire blight strikes in susceptible varieties Thinning PGR etative buds allows for spur formation and greater Reducing the number of flower buds relative to veg- The first application should be made when trees tion, apply GA3 at 2 to 4 weeks after bloom, at a rate per acre in the initial application. Subsequent appli long-term productivity. To reduce flower bud forma- have 1 to 3 inches of new growth. Apply 18 to 36 oz cations should be made every 2 to 3 weeks. Reduce - and vigor. Older trees typically need higher rates the rate in repeat applications to 9 to 24 oz per acre, of 4 to 18 grams a.i. per acre, depending on tree age than younger trees. Optimum timing is when 3 to day period, or 99 oz per acre per season. Adjust the and do not exceed a total of 48 oz per acre in any 21 3 inches of terminal shoot extension has occurred. amount of product and water according to the tree 5 terminal leaves are fully expanded, or when 1 to Similar applications can be used to prevent or re row volume.

- duce flowering in young non-bearing tart cherries.

Utah-Colorado Tree Fruit Production Guide 145 Chapter 8: Growth Regulation and Thinning

Improving Fruit Quality Managing Fruit Maturity and Abscission Preventing Apple Fruit Russet Fruit russet, rough tan to brown patches or streaks on the skin of apples, is a particularly common use of labor and other resources, and prolongs the Controlling when fruits mature allows more efficient harvest season. For example, PGR applications could by the presence of water on the fruit surface during advance fruit maturity in one portion of a block, and problem in Golden Delicious. It is typically caused delay maturity and improve storability in another. humidity, dew or rain, light frosts, and reaction to the first 45 days of fruit development. High relative some pesticides may also cause russeting. Hastening fruit maturity

Multiple applications of gibberellic acid (GA4+7) Apple Ethephon applications will advance apple maturity shown to reduce fruit russeting. Beginning at late during the 45-day period after bloom has been bloom or petal fall, apply GA4+7 (ProVide) in four This product will also shorten the storage life of by 3 to 5 days under favorable weather conditions. consecutive sprays every 7 to 10 days. Apply 10 to treated fruit, so avoid using it on any apples intend

40 oz/acre of ProVide in a single season. Excessive - 13 oz per 100 gallons (15 to 20 ppm). Do not exceed water volumes can contribute to fruit russet. Pro ed for long-term storage. Vide can be tank mixed with pesticides, but should apples. Fruit requires cool nighttime temperatures - Ethephon also improves the color of red-skinned and direct exposure to light for color development, not be mixed with spreader-stickers or nutrient even when ethephon has been applied. Proper system. sprays. Do not apply ProVide through the irrigation training and pruning is critical to allow good light

Improving Fruit Shape that color poorly may not respond adequately to eth Promalin is a combination of benzyladenine and distribution within the canopy. Cultivars and strains gibberellins (GA4+7) that can be used to increase - fruit size and “typiness” (fruit length) of lobed apple ephon application. Do not use ethephon on yellow or green-skinned cultivars to advance fruit maturity. tion of 1 to 2 pints per acre from early king bloom to ephon as well as plant sensitivity. Ideally, nighttime varieties such as Delicious. Apply a single applica- early petal fall. Alternatively, a split application can Temperature will influence the activity of eth-

temperatures should be between 55 and 65°F, and beginning of the king bloom period, followed by a development of apple fruit will not be enhanced if be made with 0.5 to 1 pints per acre applied at the daytime temperatures between 75 and 85°F. Color nighttime temperatures are above 70°F and daytime highs are above 90°F. However, maturity will still be PGR second 0.5 to 1 pints per acre application when the Thinning 2 pints per acre within a season. advanced. remaining side blooms have opened. Do not exceed Reports from Michigan and other eastern regions have shown a negative interaction between Pro harvest date in a dilute application of 1/3 to 2/3 Apply ethephon 15 to 20 days before the anticipated malin application and subsequent NAA thinning pint of ethephon plus 10 ppm NAA per 100 gallons - applications. However, this has not been as big of a of water. The ethephon will promote color develop problem in the West. ment, while the NAA slows abscission and fruit drop. - Treat only a small group of trees, no more than can be picked and packed in 3 days. Treating blocks approximately 2 to 3 days apart will allow adequate time for harvest and packing.

146 Utah-Colorado Tree Fruit Production Guide Chapter 8: Growth Regulation and Thinning

Tart Cherry Delaying Fruit Maturity Ethephon can also speed the process of fruit abscis sion (fruit drop), and has been used to synchronize Sweet Cherry - abscission layer formation to aid in mechanical Applications of gibberellin (GA3, ProGibb) can be harvesting of tart cherries. As with other fruits, used to extend the harvest season of sweet cherries. ethephon speeds the ripening and subsequent GA3 applied when fruit is translucent green to straw breakdown of cherry fruit, and may contribute to more rapid softening. However, the fruit must be at color at 16 to 48 grams a.i. per acre delays maturity or beyond the “straw” color before they will respond bright green stems and a longer storage life. GA3 by 5 to 7 days. The result is larger, firmer fruit with to ethephon. Green fruit have not yet developed the also slows color and sugar accumulation, resulting in ability to respond to ethephon. brighter color at harvest but lower soluble solids.

As in the case of apples, daytime temperatures above Apple Aminoethoxyvinyl glycine (AVG or ReTain) blocks ries can result in additional unwanted side effects the formation of ethylene by plants and can be used 85°F will result in an over response and in tart cher- such as gummosis. Weak or stressed trees should to delay maturity and to hold fruit on the tree. AVG not receive an application of ethephon as gummosis will be even more severe. can be used as a stop drop with the added benefit of has no direct affect on color development, but allow firmer fruit at harvest and a longer storage life. AVG Because daytime temperatures in the Intermountain ing the fruit to hang on the trees longer will result in - larger fruit with more color development. to tart cherry harvest, growers often reduce the rate West routinely exceed 85°F in the weeks leading up Timing is critical. Apply at the label rate 4 weeks synchronized fruit abscission but lessens the risk before anticipated normal harvest. AVG acts by pre by half, which seems to give the beneficial effect of of harmful side effects. Therefore, 1/3 to ½ pint per venting the natural abscission process from begin - acre is applied in a dilute spray two to three weeks ning. However, if this process has already started, - before harvest. All of the fruit should be at the straw AVG applications are not effective. Use at least 100 color before ethephon application. gallons per acre and spray both sides of the row (no alternate row applications) to ensure good coverage. Preventing Premature Fruit drop Some apple cultivars, particularly early ones, are Conclusion susceptible to preharvest fruit drop. Most suscep tible cultivars respond to a dilute application of NAA. - Make the application 7 to 14 days before anticipated PGRs can be a useful aid in managing orchards,

harvest at a concentration of 10 to 20 ppm. but require careful timing, mixing and application. Thinning PGR Sloppy techniques will give disappointing results and will waste time and money. With careful record Do not apply NAA within 2 days before harvest keeping, it will be possible to track from year to year treatment. If making a second application of NAA nor use more than twice per season as a stop-drop which rates, materials and environmental conditions as a stop drop, allow at least 7 days between ap produce acceptable results on each cultivar. plications. NAA used on early season cultivars can - ppm concentration and don’t apply as a low volume result in fruit splitting at maturity. Do not exceed 20 concentrate spray. NAA will shorten the storage life of treated fruit, so do not apply to any fruit intended

for long-term storage.

Utah-Colorado Tree Fruit Production Guide 147 148 Utah-Colorado Tree Fruit Production Guide Chapter 9: Nutrition

Chapter 9 Nutrition

Nutrient Sprays are rapidly deactivated at low pH values, especially

Of the various nutrients that can be limiting in Colo- those around 3.5-4.0. rado orchards, usually zinc, iron, copper, manganese, Boron calcium, magnesium, nitrogen, and boron can be in peaches and apples. However, pears are the fruit successfully corrected temporarily with sprays. Zinc Leaf analysis results show some boron deficiencies pear trees are affected by "blossom blast" or wilt- dormant sprays, while the most effective responses crop that most often shows boron deficiency. Where deficiencies are most successfully corrected through to the other nutrients are through soil applications. Iron sprays are not effective on peaches nor, pos- ing of the flower buds in early spring due to boron A single maintenance spray, applied each year at a deficiency, a spray should be applied before bloom. low rate, should supply enough boron to prevent the symptoms may respond temporarily to some of sibly, pears. Fruit trees showing severe deficiency these other nutrients applied as sprays. However, be applied at any time, late fall applications when these sprays should only be used in conjunction with development of a deficiency. While the spray may leaves are still green or spring pre-bloom applica- soil applications of the same nutrient. The sprays tions are recommended. will provide temporary relief until the soil applied

nutrient can be translocated throughout the tree. CAUTION: Do not confuse "blossom blast" with such Researchers in Utah have reported a summary of their studies on the effect of foliar nutrient sprays on

sour cherries and apples. Further information may diseases as fire blight. be obtained by contacting Dr. Ron Godin, Colorado Calcium Spray applications of calcium can reduce the inci- State University Extension, (970) 874-2195.

50 percent. Under average conditions, three sprays Alkaline Soils dence of bitter pit and cork spot in apples by 35 to June. It should be followed by a second spray in mid peaches on alkaline soils, can most times be cor- are suggested. The first should be applied about mid Chronic micro-nutrient deficiencies, typical on July and a third in mid August. With young and very vigorous trees or trees with large fruit which have a of irrigation water and/or application of elemental rected by reducing the soil pH through acidification history of serious bitter pit, more sprays may be nec- sulfur to the soil. Soil application of chelated micro- essary. Applications should begin at the same time (mid June) and should be carried on through to mid years depending on soil pH. Western Colorado soils nutrients can correct these deficiencies from 1 – 3 August. The more severe the history of bitter-pit, the more frequently should calcium be applied.

are typically deficient in boron regardless of soil pH. CAUTION: Nutrient sprays can cause phytotoxic injury to foliage and tree if not applied correctly Manganese Nutrition in the correct amounts and at the right time. To peach orchards located on highly alkaline soils. This Manganese deficiencies are especially common in through tissue analyses or visual observations. Use - avoid potential injury, verify the nutrient deficiency cies. While it may not be visually detectable, a tissue caution when using a concentrate sprayer because of deficiency is often masked by zinc and iron deficien potential injury. Some (like zinc sulfate) can cause also can be induced by applying excessive amounts - analysis will identify the deficiency. The deficiency of iron chelate. Usually one foliar application of tree injury if applied within 3-5 days of an applica be generally compatible with most fungicides and tion of oil. Others (like Leffingwell products) may insecticides if the pH is adjusted so that it remains manganese sulfate, applied when the first leaves are level of manganese in the leaves. close to neutral (pH 6-7). Pyrethroid insecticides fully expanded, is sufficient to maintain an adequate

Utah-Colorado Tree Fruit Production Guide 149 Chapter 9: Nutrition

Iron 6. Zinc sulfate is highly corrosive. The spray tank, Iron sprays with iron salts or chelates usually give pump, lines, and nozzles should be thoroughly temporary correction of chlorosis although peach trees are less likely to respond than other fruits. Soil rinsed and flushed after using. applications of chelates are much more effective 7. Foliar application during or followed by damp than foliar sprays, but need to be protected from weather may result in spray injury on some vari- breakdown by the sunlight. For soil applications, eties of stone fruits.

Dormant Application: Higher rates of zinc can be apply 2-4 oz Sequestrene 138 Fe or Ferriplus 138 or second irrigation. Distribute the material evenly applied in the spring before the buds are open than per inch of trunk diameter shortly before the first along the tree in the nearest furrow on each side of during the growing season. Sprays are more effec- the tree and cover lightly. The irrigation water will tive and appear to cause less injury when delayed as dissolve the chelate and move it into the root zone. late in the spring as possible, but before buds scales open. Zinc - Fall Application: Zinc can be applied after the trees rado. Soil applications of zinc have not proven have begun to go dormant (usually after October Zinc deficiency symptoms are common in Colo effective. Where zinc levels are known to be low, 10), but while the leaves still remain green and ac- annual spray applications should be made to avoid tive. Fall applications are usually less effective than spring dormant applications, but the former may they should be treated as soon as possible to avoid deficiency symptoms. Once symptoms are detected, further injury. cherry, both a fall and a dormant application may be be needed in cases of severe deficiency. With sweet necessary. CAUTIONS:

symptoms. Zinc sprays can cause severe injury 1. Verify need by tissue analysis or visual deficiency to shoots, buds, fruit, and leaves. Adjust the rate, formulation, and time of application according to the kind of fruit, the season of the year, and the amount of zinc required.

an application of oil can cause injury. Longer 2. Applications made within 3 days before or after periods may be required during cool weather.

of any oil-containing spray may damage apples Application of zinc sulfate spray within five days and should be avoided during that time.

of oil to pears in the spring, it may be necessary

Nutrition 3. Because of the problem of multiple applications to apply zinc in the fall instead.

4. Do not use fall applications on apricot because of potential injury.

5. When using zinc sulfate crystals, be sure all crystals are dissolved before spraying because of potential injury.

150 Utah-Colorado Tree Fruit Production Guide Chapter 9: Nutrition

Nutrient Sprays

Rate Per Use Any of the Listed 100 Gal Rate Per Nutrient Combinations (Dilute) Acre Remarks DORMANT SPRAY - Apply in spring before buds open Zinc maintenance Zinc sulfate 36% crystals 1.5-3 lb 6-12 lb See precautions in text, page 150. Zinc sulfate 0.5 lb/gal LC 0.5 gal 2 gal Tech-Flo Zeta Zinc 22 1-4 pt 1 qt Zinc deficiency Zinc sulfate 36% crystals 10 lb 40 lb See precautions in text, page 150. Zinc sulfate 1.2 lb/gal LC 3 gal 12 gal Tech-Flo Zeta Zinc 1 qt 4 qt PRE-PINK OR PINK SPRAY Boron Solubor DF 10 oz 3-4 lb Solubor: see label for further details on rates and maximum levels. maintenance Borosol 10 8-32 fl oz 1-4 qt Boron deficiency Solubor DF 1.25 lb 5 lb Solubor WP: see label for further details on rates and maximum levels and Borosol 10 8-32 fl oz 1-4 qt precautions in text, page 149. FOLIAGE SPRAY - After bloom and before harvest Boron Solubor DF 10 oz 2.5 lb Solubor WP: multiple applications at low rates are most effective; see label. maintenance Borosol 10 8 fl oz 1 qt Boron deficiency Solubor DF 1.25 lb 5 lb Solubor WP: best applied after harvest or before bloom on pears. See Borosol 10 8-16 fl oz 1-4 qt precautions in text, page 149. Multiple applications at low rates are most effective; see label. Calcium (bitter-pit Calcium chloride 3-4 lb 12-16 lb Make 3 to 5 applications as needed from reduction) mid-June to mid-August. Iron deficiency Iron chelate See label See label Follow manufacturer's directions. All chelates break down rapidly under ultra-violet (sun) light. Spray chelates in evening or on cloudy days. See text, page 150. Manganese Manganese sulfate 2 lb 8 lb Apply as soon as leaves are well deficiency developed. Zinc deficiency, Zinc sulfate 36% crystals 1.5 lb 6-12 lb See precautions in text, page 150. non-bearing trees Zinc sulfate 1.2 lb/gal LC 0.5-1 gal 2-4 gal TechFlo Zeta Zinc 0.25-1 pt 1-4 pt Nutrition Zinc deficiency, TechFlo Zeta Zinc 0.25-1 pt. 1-4 pt. Caution: certain varieties of plums, bearing trees peaches, and apricots are susceptible to zinc excesses. Magnesium epsom salts (magnesium 10-20 lb 40-80 lb Apply in 3 sprays at 14 day intervals deficiency sulfate) beginning at petal fall.

Utah-Colorado Tree Fruit Production Guide 151 Chapter 9: Nutrition

Nutrient Sprays, continued

Rate Per Use Any of the Listed 100 Gal Rate Per Nutrient Combinations (Dilute) Acre Remarks POSTHARVEST - Fall application near leaf drop Nitrogen urea 0.5-2.5 lb 2-10 lb Use only formulations containing 2% or deficiency (apple less biuret because of injury risk to tree only) and fruit. Boron Solubor 20.5WP 0.5 lb 2.5 lb See labels and text, page 149. maintenance Borosol 10 8 fl.oz 1-4 qt Boron deficiency Solubor 20.5WP 1 lb 5 lb See labels and text, page 149. Borosol 10 1-2 pt. 1-4 qt Copper deficiency copper sulfate 53% 1 lb 4 lb Kocide 101 (50%) 1 lb 4 lb Kocide DF (40%) 1.2 lb 4.8 lb Nitrogen urea 2.5-5 lb 10-20 lb Apples only. May damage other fruit supplement crops. Apply before leaf drop. Zinc maintenance zinc sulfate 36% 1.5-3 lb 6-12 lb Not on apricots. See text, page 150. TechFlo Zeta Zinc 0.25 qt 1 qt Zinc deficiency zinc sulfate 36% 2.5-5 lb 10-20 lb Not on apricots. See text, page 150. TechFlo Zeta Zinc 1 qt 4 qt Nutrition

152 Utah-Colorado Tree Fruit Production Guide Chapter 10: Irrigation

Chapter 10 Orchard Irrigation

Proper irrigation is essential to maintaining a available water represents about 50% of the healthy and productive orchard. Over irrigation total available water in the soil. (Fig 10.2.) slows root growth, increases iron chlorosis in al- kaline soils, and leaches nitrogen, sulfur and boron The goal of a well-managed irrigation program is to

Over irrigation can also induce excessive vegetative the point of allowable depletion, or in other words, out of the root zone leading to nutrient deficiencies. maintain soil moisture between field capacity and vigor. Excessive soil moisture also provides an en- to make sure that there is always readily available vironment ideal for crown and collar rots. Applying water.

and reduced fruit size and quality. insufficient irrigation water results in drought stress Fruit development is driven by available water. Where inadequate water is supplied, particularly

fruit size will be reduced. during the final stages of fruit development, harvest Properly managing irrigation is analogous to manag- ing money. In addition to knowing your current bank balance (soil water content), it is important to track both expenses (evapotranspiration) and income (rainfall and irrigation).

Bank Balance (Soil Water Content)

Fig. 10.1. Soil water content from saturated to dry. How big is my bank account? – Water Optimal levels for plant growth are between field capacity and allowable depletion. holding capacity

First, some terminology: • Field Capacity is the amount of water that The amount of readily available water is related to can be held in the soil after excess water has the effective rooting depth of the plant, and the wa- percolated out due to gravity. ter holding capacity of the soil. The effective rooting • Permanent Wilting Point is the point at which depth depends on soil conditions, variety and root- the water remaining in the soil is not available stock. Although tree roots can grow to several yards for uptake by plant roots. When the soil water depth, nearly all of the roots of a mature tree are content reaches this point, plants die. typically in the top 2 to 3 feet (Atkinson, 1980). The • Available Water is the amount of water held in water holding capacity within that rooting depth

is related to soil texture, with coarser soils (sands) Irrigation wilting point. (Fig. 10.1.) the soil between field capacity and permanent silts and clays (See Table 1.). A deep sandy loam soil • Allowable Depletion (readily available) is holding less water than fine textured soils such as the point where plants begin to experience 2.25 inches of readily available water in an effective drought stress. For most fruit trees, the at field capacity, for example, would contain 1.8 to rooting depth of 3 feet. amount of allowable depletion, or the readily

Utah-Colorado Tree Fruit Production Guide 153 Chapter 10: Irrigation

measures electrical resistance. Resistance measure- ments are then related to soil water potential, which is an indicator of how hard the plant roots have to “pull” to obtain water from the soil. The handheld unit reports soil moisture content in centibars, where values close to zero indicate a wet soil and high values represent dry soil. The relationship between soil water potential and available water dif- fers by soil type. The maximum range of the sensor is 200 centibars, which covers the range of allow- able depletion in most soils. The sensors are less effective in coarse sandy soils, and will overestimate Fig. 10.2. The amount of allowable depletion, or the read- ily available water, represents about 50 percent of the total soil water potential in saline soils. Remember that available water. allowable depletion is 50% of available water, which roughly corresponds to soil water potentials of 50 Table 10.1. Available water holding capacity for different soil centibars for a loamy sand soil, and 90 centibars for textures, in inches of water per foot of soil. Available water is a loam (Table 10.2, 50% depletion threshold values the amount of water in the soil between field capacity and per- for each soil texture). manent wilting point. Readily available water is approximately 50% of available.

Readily available Table 10.2. Recommended Watermark™ sensor values at Soil Available (inches) which to irrigate. Texture (inch/foot) 2 ft root 3 ft root Irrigation Needed Soil Type depth depth (centibars) Sands and Loamy sand 40 - 50 0.5 - 0.75 0.5 - 0.75 0.75 - 1.13 fine sands Sandy loam 50 - 70 Loamy sand 0.8 - 1.0 0.8 - 1.0 1.2 - 1.5 Loam 60 - 90 Sandy loam 1.2 - 1.5 1.2 - 1.5 1.8 - 2.25 Silt loam, silt 70 - 90 Loam 1.9 - 2.0 1.9 - 2.0 2.85 - 3.0 Clay loam or clay 90 - 120 Silt loam, silt 2.0 2.0 3.0 TMWatermark is a registered trademark of Irrometer, Co., Riverside, Silty clay CA. 1.9 - 2.0 1.9 - 2.0 2.85 - 3.0 loam Sandy clay loam, clay 1.7 - 2.0 1.7 - 2.0 2.6 - 3.0 loam Expenses – Evapotranspiration

Water is lost from the orchard through surface run- What’s in the bank? -- Measuring Soil off, deep percolation (moving below the root zone), Moisture evaporation from the soil surface, and transpiration In order to assess soil water content, one needs through the leaves of the plant. Of these, the biggest to monitor soil moisture at several depths, from losses are typically due to evaporation and transpi- just below the sod layer or cultivation depth (4 to ration, collectively known as “evapotranspiration” 6 inches), to about 70 percent of effective rooting or ET. Deep percolation from excess irrigation can depth (2 feet). One of the more cost effective and be another large loss. Estimates of ET are based on Irrigation reliable methods for measuring soil moisture is by weather data, including air temperature, sunshine, electrical resistance block, such as the WatermarkTM relative humidity and wind speed. Some weather sensor (Irrometer Co., Riverside CA). These blocks stations in Utah and Colorado are programmed to are permanently installed in the soil, and wires from calculate and report the ET estimates for alfalfa as a

the sensors are attached to a handheld unit that reference crop (ETref or ETr).

154 Utah-Colorado Tree Fruit Production Guide Chapter 10: Irrigation

Typical weekly ETr values are shown in Table 10.3. The Kcrop for apples is shown in Fig. 10.4. At full

Calculated ETr for your location can be determined bloom (Growth Stage = 0), an apple orchard is using by accessing weather data from a nearby weather about 20% of the amount of water used by the alfalfa station in Utah at: climate.usu.edu/stationstuff, or in reference crop. Water use increases dramatically Colorado at: ccc.atmos.colostate.edu/~coagmet/. until the full canopy is established (growth stage = 100) when water use is 95% of a reference alfalfa Table 10.3. Typical weekly alfalfa reference evapotranspiration crop. Water use increases slightly during the sec- (ET) values for Utah locations. r ond phase of fruit growth (mid-season to harvest) Location May June July Aug. when water use is at 100% of the reference alfalfa Logan 1.38 1.83 1.94 1.68 crop. After harvest (growth stage = 170), water use Ogden 1.48 1.98 2.10 1.80 quickly decreases. Spanish Fork 1.48 1.94 2.08 1.74 Santaquin 1.47 1.92 2.03 1.67 Moab 1.63 2.08 2.19 1.87 Cedar City 1.57 1.95 2.04 1.74 St. George 1.95 2.40 2.53 2.02 Calculated from consumptive water use tables (Hill, 1994)

The ET of your crop can be determined by multiply-

ing the ETr (K crop by a correction factor or crop coefficient development. ) that is specific to your crop and its stage of

ETcrop = ETr × Kcrop

The K for peach is shown in Fig. 10.3. At full crop Fig. 10.4. Crop coefficients for apples, based on an alfalfa bloom (Growth Stage = 0), a peach orchard is us- reference crop. ing about 20% of the amount of water used by the alfalfa reference crop. Water use increases gradu- ally as the canopy develops until the full canopy is The Kcrop for sweet cherry is shown in Fig. 10.5 and established (growth stage = 110) when water use is differs depending on whether or not the alleys have 95% of a reference alfalfa crop. Water use increases grass or are clean cultivated. At bud break (Growth slightly during fruit ripening, then drops below 90% Stage = 0), a cherry orchard with grass between after fruit harvest (growth stage = 140). Water use rows is using about 40% of the amount of water increases again during the late season then declines used by the alfalfa reference crop, compared to 20% during leaf senescence. under clean cultivation. Water use increases until full bloom and fruit set (growth stage = 100) when water use is 105% of a reference alfalfa crop with grass cover and 80% without. By leaf senescence in the fall (growth stage = 200), water use has de- creased to 40% of the reference crop.

Irrigation - lished, but are likely similar to sweet cherry. Crop coefficients for tart cherry have not been pub

Fig. 10.3. Crop coefficients for peach, based on an alfalfa refer- ence ET. Adapted from Johnson et al. (2000). Full bloom = 0, full canopy = 110; fruit harvest = 140; leaf drop = 200.

Utah-Colorado Tree Fruit Production Guide 155 Chapter 10: Irrigation

distance the water travels through the irrigation points of your field. Elevation differences and the lines both affect water pressure, and consequently - tion, you can place catch cans under the emitters the flow rate at the nozzle. If you have trickle irriga from each emitter and emitter spacing can be used and determine flow rate for each emitter. Flow rate to calculate rate per area.

much you have to over water the wettest spots in The efficiency of your system is a measure of how the orchard to get adequate water to the dry spots.

and to the amount of evaporation that occurs before Efficiency is related to the uniformity of application the water can move into the soil. A well-designed microsprinkler or drip system can be 70 to 90% ef-

ficient. Overhead sprinkler systems are typically 60 Fig. 10.5. Crop coefficients for cherries with clean cultivated to 75% efficient, while flood and furrow irrigation is or grass cover row middles. typically 30 to 50% efficient. Case Study Income – Irrigation and Rainfall

In the high elevation desert climate of the Inter- Following is an example of how to calculate water mountain West, rainfall contributes a small fraction needs for a mature peach orchard just prior to fruit of the in-season water requirements of the crop. harvest. The orchard is on a deep sandy loam soil Therefore, regular irrigation is needed to supply with row middles planted to grass cover. orchard water needs. This irrigation water can be Water use (Expenses) lines or microsprinklers. • ET values are 2.10 inches per week supplied by flood, furrow, impact sprinklers, drip r (weather station data). Whichever irrigation system you utilize, it is im- • portant to calibrate your system so that you know 130, from Figure 10.3). precisely how much water is being applied. With Crop coefficient is 0.98 (Growth stage = ET = ET × K sprinklers and microsprinklers, the simplest way to • crop r crop

do this is to place catch cans in multiple locations in • ETcrop = 2.10 inches/week × 0.98 = 2.06 your planting and collect water for a set period of inches/week time. The amount of water collected over time will give you an application rate (inches per hour), and Soil storage capacity (potential bank balance) differences in water collected among the catch cans • The total storage capacity for readily will tell you how uniform the application is within available water over the 2-foot effective your planting. rooting depth is 1.5 inches (Table 10.1). Irrigation • 1.5 inches ÷ 2.06 inches per week = 0.73 When trying to determine application uniformity, it weeks or 5.1 days between irrigations. is best to measure output at both ends of your irriga- tion system. Also, if your planting is on a slope, you Restated, soil moisture in the root zone will go should measure output at the highest and lowest from capacity to plant stress levels in 5.1 days.

156 Utah-Colorado Tree Fruit Production Guide Chapter 10: Irrigation

Additional Resources 1.5 inches of water. Assuming a microsprinkler ir- To recharge the soil profile, you will need to add inches of water application will be required per rigation system with an efficiency of 80%, 1.9 acre - acre for each watering. - AgriMet Crop Coefficients, Pacific Northwest Region ment of the Interior. www.usbr.gov/pn/agrimet/ al office of the Bureau of Reclamation, U.S. Depart Summary cropcurves/crop_curves.html.

Atkinson, D. 1980. The distribution and effective- Good irrigation management requires: ness of the roots of tree crops. Horticultural Re- views 2:424-490. 1. An understanding of the soil-plant-water relationship. Faust, M. 1989. Physiology of Temperate Zone Fruit 2. A properly designed and maintained irrigation

Trees. Wiley and Sons, New York. the system. Irrigation Scheduling Techniques. Water Conserva- system, and a knowledge of the efficiency of 3. Proper timing based on: - istry of Agriculture and Food. March 1997. www.agf. a. Soil water holding capacity. tion Factsheet. No. 577.100-1. British Columbia Min gov.bc.ca/resmgmt/publist/500series/577100-1. b. Weather and its effects on crop demand. pdf. c. Stage of crop growth. Johnson, R.S., J. Ayars, T. Trout, R. Mead and C. Phene. Each of these components requires a commitment to well correlated with midday canopy light intercep- proper management. Proper irrigation management 2000. Crop coefficients for mature peach trees are tion. Acta Hort. 557:455-460. optimize orchard yields in balance with long term will provide the most efficient use of water, and will Hill, R.W. 1994. Consumptive Use of Irrigated Crops orchard health and productivity. in Utah. Utah Ag. Exp. Stn. Res. Rpt. #145. Utah State University, Logan UT. www.waterrights.utah.gov/ techinfo/default.asp.

Smith, T. Irrigating Tree Fruits for Top Quality. Washington State University Extension. www.ncw. wsu.edu/ treefruit/irrigation/how.htm. Irrigation

Utah-Colorado Tree Fruit Production Guide 157 158 Utah-Colorado Tree Fruit Production Guide Chapter 11: Cold Effects on Fruit/Bud Phenology

Chapter 11 cold Effects on fruit/Bud Phenology

Evaluating Tree Fruit Bud & Fruit individual flowers within a multiple-flower bud have Damage From Cold buds will need to be cut individually by an angled, separated out and have longer flower stems, flower Freeze/frost events can damage fruit buds and young damage evidenced by tissue darkening. Crops with fruit. The level of damage is directly related to cold vertical cut to examine the flower pistil structures for simple buds (apricots, peaches and nectarines) will intensity and duration as well as bud developmental require cutting of each simple bud. stage. Data obtained from research done in Washing- ton State has been used to develop critical temperature charts that relate bud developmental stage with cold with a vegetative bud between them at each node. injury and these are posted on the internet at several In peaches and nectarines, the flower buds are in pairs They can easily be cut in pairs clear up through bloom locations including Colorado State University – West- with an angled vertical cut to show the pistil structures ern Colorado Research Center’s web page: www.colo- of both buds within the pair at the same time. Because state.edu/programs/wcrc/pubs/research_outreach/ apricot buds tend to be in clusters, the buds will have fruitinfo.htm and click on the critical temperature chart of your crop choice. The charts include color done using either a hand lens or a dissecting micro- photos of the bud stages and development. to be cut individually. In all cases, examination is best scope. This is especially the case in early winter when freeze events in order to determine future protection internal flower structures are extremely small and Growers can benefit from evaluating damage following efforts and thinning programs. The following de- until the flowers are nearly ready to open. Evaluation of bud and fruit damage begins with collec- scribes how one does such an evaluation. 100 buds for evaluation, collected on shoots from dif- Fruit crops differ in bud structure and arrangement tion of shoots with flower buds. The target is around fering heights within the tree and locations within an on the shoots. Apricots, peaches, and nectarines orchard block. Varieties should be kept separated and have simple flower buds with a single flower within brought back from the orchard, the base of the shoots arranged in pairs (rarely in three’s) on last season’s bundled with flagging tape and a label. These are then each flower bud. In peaches and nectarines, buds are placed into a bucket (or a can) with water, and allowed to warm up at 70°F for a minimum of 2 hours to allow buds. Apricots, like cherries and plums, may have shoots with a single vegetative bud between the flower the damaged tissue to darken due to oxidation of phe- nolic compounds released by the injury. Discoloration shoots or clusters of simple buds on short branches, single to multiple flower buds on the last season’s hours is better than 2 hours for detection purposes. intensifies within injured tissues with time, so four called spurs. Apple, pear, cherry, and plum have flower and pear buds are positioned as single buds on spurs buds with multiple flowers within a single bud. Apple Buds are then cut and examined for brown to black or along last year’s shoots; cherry and plum buds discoloration of the fruit pistil (young fruit within shoots or on short spurs. have single to multiple flowers buds in clusters on the sweet cherries need about 50% of the buds produced the flower, Fig. 11.1). A general rule of thumb is that the previous summer in order to have a full crop; all Fruit buds pass through up to eight stages in develop- the other tree fruits (apple, pear, apricot, peach, nec- ment from fully dormant to full bloom (shown at the tarine, and plum) need only about 10% for a full crop. end of this chapter). At the early stages, the buds are Effects Cold The cutting process requires a very sharp razor blade; pear, cherry, plum) can be done horizontally across the fairly tight and cuts on multiple-flower buds (apple, single edge blades work well because they are stiffer and easier to control for cutting. They are quite inex- cut if the cut is properly positioned. Later, once the bud to examine all the flowers within the bud at one

Utah-Colorado Tree Fruit Production Guide 159 Chapter 11: Cold Effects on Fruit/Bud Phenology

Fig. 11.1. Fantasia nectarine buds, cut longitudinally to show the pistil, one live and one dead. (photo by HJ Larsen)

Fig. 11.3. Berenda Sun peach buds (first pink stage) cut verti- cally to expose the pistil for freeze injury evaluation. Arrows: damaged or dead pistil (right side each photo). A. Right bud shows pistil damaged by freeze the prior night; note brownish discoloration of pistil. B. Right bud shows pistil killed by freeze 2 - 3 weeks prior to evaluation. Note smaller size and darker brown color of the older freeze-killed pistil in B than in A. (photos by HJ Larsen)

Fig. 11.2. Berenda Sun peach buds (first swell stage) cut verti- cally to show pistils. A. Both buds alive. B. Both buds dead. (photo by HJ Larsen)

pensive and can be discarded when the cutting edge becomes dull or damaged.

Apricot, peach, and nectarine buds are easiest to cut by

on a vertical diagonal (Fig. 11.2). Buds in later stages starting at the base of the bud (or flower) and cutting of development (near bloom) often are best evaluated by simply cutting the petal corolla vertically to expose the entire pistil to view for evaluation. Buds killed Fig. 11.4. Apricot buds (full bloom stage) cut vertically to within the past day or two will have pistils that are expose the pistil for freeze damage evaluation. Note the black- ened pistil on the right, killed by the prior night freeze (photo the same size or only slightly smaller than live pistils by HJ Larsen). while buds killed several weeks previously will have a very small pistil with a much darker discoloration (Fig. 11.3). Pistils often develop discoloration within hours When evaluating damage of young fruit, the cut should at room temperature after being killed; apricot pistils be made horizontally through the fruit about 1/3 Cold Effects often turn a blackish brown (Fig. 11.4). the distance from the stem end to the stylar end in order to cut through the embryo structure called the

160 Utah-Colorado Tree Fruit Production Guide Chapter 11: Cold Effects on Fruit/Bud Phenology

Fig. 11.6. Bing sweet cherry buds (multiple-flower buds) cut horizontally across the bud for flower viability evaluation. Ar- rows: D = dead flowers (dark brown color), L = live flower. (photo by HJ Larsen)

Fig. 11.5. Young nectarine cut to show embryo attachment (funiculus, arrows) to the fruit tissue. A. Cut orientation and location. B. Young embryo with undamaged funiculus. C. Thin section to emphasize embryo and undamaged funiculus). D. Twin embryos with damage within each funiculus; note the brown discoloration. (photos by HJ Larsen) funiculus, which is a connection to the exterior fruit tissue (Fig. 11.5). A vertical cut can also be used if one cuts through the suture (fruit crease) to the back of Fig. 11.7. Sweet cherry flowers killed by frost at bloom, cut vertically to expose the blackened pistil. (photo by HJ Larsen) the funiculus often kills the embryo within the young the fruit, but that often is more difficult. Damage to fruit (causing fruit dropping in mid-June) or stops development. For peach and nectarine, this can be seen at harvest, when the frost occurred at shuck-fall. have differing timing for bloom, it is difficult to see all the flowers at one time. Often the most advanced flower will be the highest (furthest from the base of Sweet cherry, plum, apple, and pear buds are multiple- (closest to the base of the bud). The earlier in bud de- the bud) and the least advanced flower be the lowest velopment that the evaluation is done, the greater the flower buds (more than one flower inside each bud). Plums typically have two flowers per bud, cherries or near bloom, one needs to use more angled vertical pears typically have six or more. But both plums and possibility of seeing all the flowers within the bud. At usually have two to five (Fig. 11.6), and apples and cuts to reveal the pistils (Fig. 11.7).

Apple and pear buds, like plum, tend to have differing Effects cherries can have only a single flower within a bud if Cold some flower initials are killed by winter injury. timing for opening of the flowers within the fruit bud. A horizontal cut through these multiple-flower buds In apples, the “king bloom” is the first to open and will cut through several of the flowers they contain. typically has five “side bloom” flowers forming a ring However, because the flowers within these buds often Utah-Colorado Tree Fruit Production Guide 161 Chapter 11: Cold Effects on Fruit/Bud Phenology

Fig. 11.8. Apple buds cut to show cold injury damage; arrows show killed pistil tissues. A. Longitudinal section (left flower Fig. 11.9. Pear buds. A. Pear bud showing the multiple-flowers killed). B - D: Cross-sections of flower buds. B. Six live flowers bud type. B. Longitudinal section showing pistil compound style (King bloom in center); C: King bloom pistil killed, side blooms (arrow points to stylar bundle leading to fused ovary recep- still alive; D: King bloom and two side blooms killed, two top tacle). C & D. Cross-section cut through the multiple flowers; C side blooms alive. is higher level cut, D is next cut lower; arrows in C & D point to stylar clusters with tissue browning that could indicate cold damage and death of the stylar tissues. (photos by HJ Larsen) around it (Fig. 11.8, b). Because it is earliest, it typi- cally will be positioned toward the top of the bud when

toward the top (Fig. 11.9). This makes cold injury dam- - flowers tend to develop from the base of the shoot one makes a horizontal cut through the flower bud. age evaluation even more dependent of multiple cuts ing temperatures, injured tissues of the style and ovary When flower structures are damaged by frost or freez through the developing buds. As with apple, damage will darken through formation of phenolic compounds to and discoloration of the stylar tissue within the in response to injury (Fig. 11.8, a). Cross-sectional cuts blossom following exposure to freezing temperatures

structures for by making sequential cuts beginning at through the flower will reveal these darkened flower the upper top of the bud and proceeding toward the often is associated with death of the flower (Fig. 11.9, base of the bud. Because the style (the central portion b - d). Pear has a tendency to develop late flowers at of the pistil) is so much longer than the stigma (top the tips of shoots (these are commonly termed “rat-tail damage and set fruit, but the fruit usually is substan- portion of the pistil), it is typically the structure seen bloom”). These late flowers can escape earlier frost tially smaller and lower in quality. in the cross-sectional cuts through the upper portion

Very late frost events after petal-fall can cause injury and d). Browning of this structure after a frost event of the flower where the petals are found (Fig. 11.8, c to young fruit tissues and impact fruit quality and appearance (Fig. 11.10). Sweet cherry fruit exposed will not become a successful fruit. is a good indication that the flower has been killed and Cold

Effects young peach fruit can result in fruit that never sizes to cold can be killed outright (Fig. 11.10, a). Injury to beyond the size of a walnut. This can readily be seen even greater as they approach bloom. However, the In pears, the spread in flower stage of development is as non-damaged fruit approaches ripeness (Fig. 11.10,

162 Utah-Colorado Tree Fruit Production Guide Chapter 11: Cold Effects on Fruit/Bud Phenology

Fig. 11.10. Late frost injury to young fruit. A. Sweet cherry: d = killed young cherry fruit. B. Peach: h = healthy, maturing fruit; d = damaged, non-maturing fruit. C. Apple with frost ring. D. Pears with frost ring. (photos by HJ Larsen) b). Frost injury to apple and pear fruit kills the surface cold injury may need to include late fall/early winter, cells and tissues, causing a pronounced scabby pattern especially if a rapid drop to potentially damaging temperatures is forecasted to follow prolonged warm 11.10, c & d). Such affected fruit, although edible, are weather that slows cold acclimation by the buds. on the fruit surface that is termed “frost ring” (Fig. not salable and often are removed by hand thinning if possible. Finally, bud viability can also be assessed by forcing

Researchers working on cryopreservation of fruit buds buds on them, place them promptly into water and buds to bloom indoors. Cut some shoots with flower have noted that buds that are frozen before they have keep them at room temperature for several weeks. Re- cut the shoot ends every 5 days, so that the vascular had oxidative browning of the vascular tissues leading tissue will continue absorbing water. Most tree fruits cold acclimated (i.e., Sept., Oct., or early Nov.), often to the buds. Buds with such damage could not be suc- accumulate around 400 Growing Degree Hours (GDH) cessfully grafted for subsequent germplasm recovery. per day when held at 70°F, and need between 4,000 This type of injury can occur from a late fall or early and 7,000 GDH to reach bloom. Thus, viable buds winter freeze, especially where mild temperatures precede a freeze event, but not after mid-winter when in water at 70°F. Apricots, peaches, and plums often

should bloom within 10 to 16 days when incubated Effects these tissues are very cold hardy. Buds damaged in complete chill requirements between late December Cold this manner may open, but subsequently fall off in late and mid-January in western Colorado; cherries, apples, spring/early summer as water stress becomes an is- and pears often complete their chill requirements sue. Consequently, fruit bud protection efforts against between late January and late February.

Utah-Colorado Tree Fruit Production Guide 163 Chapter 11: Cold Effects on Fruit/Bud Phenology Tree Fruit Growth Stages and Critical Temperatures – APPLE

Typical temperatures in Fahrenheit, at which 10% and 90% To have a full crop of cherries requires well over 50% bud injury after 30 minutes exposure, is provided under each survival in most years, while apples, pears, and peaches may bud stage image. only need 10-15% bud survival.

Silver Tip Green Tip Half-inch Green 10% kill 15 18 23 90% kill 2 10 15

Tight Cluster First Pink (Pink) Full Pink (Open Cluster) 10% kill 27 28 28 90% kill 21 24 25

First Bloom (King Bloom) Full Bloom Post-bloom 10% kill 28 28 28 90% kill 25 25 25 Cold Effects

164 Utah-Colorado Tree Fruit Production Guide Chapter 11: Cold Effects on Fruit/Bud Phenology Tree Fruit Growth Stages and Critical Temperatures – PEAR

Swollen Bud (Scale Separation) Bud Burst Green Cluster (Tight Cluster) 10% kill 15 20 24 90% kill 0 6 15

White Bud (First White) Full White First Bloom (King Blossom) 10% kill 25 26 27 90% kill 19 22 23

Full Bloom Petal Fall (Post Bloom) 10% kill 28 28 90% kill 24 24 Effects Cold

Utah-Colorado Tree Fruit Production Guide 165 Chapter 11: Cold Effects on Fruit/Bud Phenology Tree Fruit Growth Stages and Critical Temperatures – CHERRY

Swollen Bud (First Swell) Green Tip (Bud Burst) Tight Cluster Sweet Cherry Tart Cherry Sweet Cherry Tart Cherry Sweet Cherry Tart Cherry 10% kill 17 15 25 26 26 26 90% kill 5 0 14 22 17 24

White Bud (First White, Popcorn) First Bloom Full Bloom Sweet Cherry Tart Cherry Sweet Cherry Tart Cherry Sweet Cherry Tart Cherry 10% kill 27 28 28 28 28 28 90% kill 24 24 25 24 25 25

Petal Fall (Post Bloom) Sweet Cherry Tart Cherry 10% kill 28 28 90% kill 25 25 Cold Effects

166 Utah-Colorado Tree Fruit Production Guide Chapter 11: Cold Effects on Fruit/Bud Phenology Tree Fruit Growth Stages and Critical Temperatures – Peach/Nectarine

Swollen Bud (First Swell) Calyx Green 1/4” green (Calyx Red) 10% kill 18 21 23 90% kill 1 5 9

Pink (First Pink) First Bloom Full Bloom 10% kill 25 26 27 90% kill 15 21 24

Post Bloom (Petal Fall) Shuck Split 10% kill 28 28 90% kill 25 25 Effects Cold

Utah-Colorado Tree Fruit Production Guide 167 Chapter 11: Cold Effects on Fruit/Bud Phenology Tree Fruit Growth Stages and Critical Temperatures – Apricot

First Swell (Bud Swell) Tip Separation (Swollen Bud) First White 10% kill 15 20 24 90% kill --- 0 14

First Bloom Full Bloom In the Shuck (Petal Fall) 10% kill 25 27 27 90% kill 19 22 24

Shuck Split (Post Bloom) 10% kill 28 90% kill 25 Cold Effects

168 Utah-Colorado Tree Fruit Production Guide Chapter 11: Cold Effects on Fruit/Bud Phenology Tree Fruit Growth Stages and Critical Temperatures – Plum

Swollen Bud Bud Burst Green Cluster 10% kill 14 20 24 90% kill 0 7 16

White Bud Bloom Petal Fall 10% kill 26 28 28 90% kill 22 33 33 Effects Cold

Utah-Colorado Tree Fruit Production Guide 169 170 Utah-Colorado Tree Fruit Production Guide Chapter 12: Pesticide Information

Chapter 12 Pesticide information

Pesticide Regulation, Safety, and In Utah, applicants can pick up study materials at Storage the Utah Department of Agriculture and Food in Salt

an appointment to take the exam, and allow two Emergency Information Lake City or at any UDAF District Field Office. Make hours. The poison control hotline for every U.S. state is Private applicators’ exams (general and agri- (800) 222-1222. culture) are open-book and the fee is $20 and • the license lasts 3 years. To recertify, you can Depending on where you are calling from, the poison re-take the exams or obtain 9 total CEU units. control center for that state will respond. In Utah, it is the Utah Poison Control Hotline in Salt Lake City, Commercial applicators’ exams cost $65, and the and in Colorado, the Rocky Mountain Poison and license lasts three years. Business owners must • Drug Center in Denver. The hotline is staffed 24/7 to also obtain a license. The applicant must have provide treatment recommendations and referral to 70% to pass. To recertify, you can re-take the an emergency medical facility. exams or obtain 24 total CEU units.

Restricted Use Pesticides and Utah Department of Agriculture and Food Obtaining a Pesticide Applicator Division of Plant Industry License 350 North Redwood Road Salt Lake City, UT 84114 - 801-538-7185 tain pesticides, or uses of pesticides, as restricted if The Environmental Protection Agency classifies cer www.ag.utah.gov/divisions/plant/pesticide/ they could cause harm to humans or to the environ- applicators ment unless it is applied by applicators who have the knowledge to use these pesticides safely. These are In Colorado: called Restricted Use Pesticides, and they are avail- private applicator license must request training materials plus the exam from applicators or persons under their direct supervi- • Applicants for able for purchase and use only by certified pesticide the Colorado Department of Agriculture website sion. for a fee of $20. Once the applicant passes, he/ she must then request the license through the NOTE: All restricted use pesticides included in the website or by phone, which costs $75 and is spray tables in this guide are followed by a small active for 3 years. To recertify, either retake the R (R). exam or earn 7 CEU credits. - Commercial applicator tors: private and commercial. A private applicator The EPA defines two categories of pesticide applica for all businesses plus employees that are apply- is a person who uses (or supervises the use of) • certification is required ing restricted-use pesticides. Exams cost $100 restricted use pesticides on agricultural lands owned and the license for individuals costs $100 and or rented by that individual or his/her employer. lasts 3 years. To recertify, either retake the ex- The private applicator may not apply restricted use ams or earn the appropriate number of credits. pesticides on another person’s property if he/she is The Colorado Department of Agriculture to receive monetary compensation. A commercial Division of Plant Industry 700 Kipling St., Suite 4000 supervises the use of any pesticides for monetary applicator is defined as any person who uses or Lakewood, CO 80215-5894 compensation. Both categories require an applica- (303) 239-4186 Information

www.cepep.colostate.edu Pesticide differ among the two. tor’s license; however, the testing and recertification

Utah-Colorado Tree Fruit Production Guide 171 Chapter 12: Pesticide Information

Pesticide Record-keeping Utah’s Groundwater and Pesticide Federal laws requires that private and commer- Program cial applicators maintain pesticide records for all Approximately half of the groundwater withdrawn applications of restricted use products for at least from wells in Utah is used for agriculture. Slightly two years. The laws are enforced through the state less than half of the population of Utah depends departments of agriculture. Applicators can develop on groundwater as a source of drinking water. In their own format for record-keeping. Spray dates 1997, The Utah Department of Agriculture and Food must be recorded within 14 days after the applica- enacted the Groundwater/Pesticide State Manage- tion is made, and must include: ment Plan. The plan outlines steps towards protect- ing groundwater from pesticide contamination and 1. Name and address of property owner response to a pesticide detection in groundwater. 2. Location of treatment site, if different from above, crop treated, and size of area If a pesticide has been detected in groundwater, then 3. Target pest a groundwater monitoring plan will be implemented 4. Exact date of application in the area to determine the extent and, if possible, 5. Brand name and EPA registration number of the source of pesticide contamination. The UDAF pesticide used will work with the landowner to prevent further 6. Total amount of product applied groundwater contamination. A number of different 7. Name and license number of the applicator farming practices, called Best Management Practices Because Worker Protection Standards require the possibility of pesticides entering the system. (BMPs), and simple devices can significantly reduce BMPs will be required by the EPA as a condition of recommended that comparable records be kept of worker notification of all pesticide applications, it is future use of the pesticides. all pesticide applications. This will also enable the grower to complete a listing of pesticides used at the - time of harvest. Packing sheds and processors are cides to monitor, due to their high potential to leach increasingly requiring pesticide usage lists. The EPA has identified five broad-spectrum herbi into groundwater and to be a possible detriment to public health, safety, and the environment. The pes- EPA Worker Protection Standard ticides are: alachlor, atrazine, cyanazine, metolachlor, EPA’s Worker Protection Standard (WPS) for agri- and simazine. Each has been detected in groundwa- cultural pesticides is a regulation aimed at reducing ter in several states, with some detections exceeding the risk of pesticide poisonings and injuries among drinking water standards. agricultural workers and pesticide handlers. The WPS offers protections to agricultural workers and pesticide handlers. The WPS contains requirements Pesticide Storage and Disposal In general, pesticides should always be stored in a safe location. The storage facility should be kept applications, use of personal protective equipment, for pesticide safety training, notification of pesticide locked so that children and other unauthorized restricted-entry intervals after pesticide application, people cannot enter and be exposed to pesticide decontamination supplies, and emergency medical hazards. All pesticides should be kept in their assistance. original containers, closed tightly, and with their original labels. If the label has come off or is coming Avoiding Drift, Runoff, Spills off, paste or tape it back on. All pesticides should be Pesticides that enter the environment can cause protected from excessive heat, and liquid pesticides injury to humans, animals, and non-target plants. should be stored in an area protected from freezing. Whenever sprays are necessary, only apply when weather conditions are appropriate, application Growers are urged to review their annual pesticide equipment is properly calibrated, and pesticide needs and stocks on hand well in advance of the formulation, droplet size, and adjuvants are used to growing season to prepare for disposal of unused minimize drift and runoff. product. Pesticide purchases should be based on Pesticide Pesticide

Information 172 Utah-Colorado Tree Fruit Production Guide Chapter 12: Pesticide Information

the amount projected for use within any given sea- The storage limit of an EHS pesticide is called the son. Empty containers should be triple-rinsed and Threshold Planning Quantity (TPQ), given in amount drained; they often can then be disposed of through of active ingredient. The limit for an accidental spill regular trash collection, but be sure to check the is referred to as the Reportable Quantity (RQ). label and local regulations. Never dispose of pesti- cides or containers by dumping them into the sewer, When a farm facility exceeds a storage limit (TPQ), sink, or toilet. Municipal water treatment practices or has an accidental spill (RQ), the information must remove little of the pesticides, and such careless be reported within 60 days (Tier 1 report). In ad- disposal can contaminate waterways and is subject dition, an annual report (Tier II report) is also due to penalties. The best means to dispose of such pes- ticides is to use them up according to their labeled EPA offers reporting software. every March 1 only if a Tier 1 report has been filed. instructions. Both Utah and Colorado departments of agriculture occasionally hold pesticide disposal The farm facility is responsible for distributing re- drop-offs with no questions asked. ports to the state, local emergency planning commit-

where and how to distribute reports, contact: tee, and local fire departments. To determine exactly EPCRA & The Fruit Grower The Emergency Planning and Community Right-to- Utah: know Act was enacted in 1986 and requires that any Mike Zucker Utah Division of Env. Response and Remediation as “Extremely Hazardous Substances” (EHS) provide 195 North 1950 West facility that stores chemicals identified by the EPA a report when storage or accidental spill of an EHS Salt Lake City, Utah 84116 occurs over a given threshold. The report is used in 801-536-4100 local community emergency planning and to provide www.superfund.utah.gov/spills.htm local governments and residents access to informa- Colorado: Colorado Emergency Planning Commission tion about specific chemicals. Fruit growers should be aware of this reporting c/o Colorado Dept of Public Health & Environment requirement because some of the EHS materials on SARA Title III -- Tier II Reports, OEIS - B2 the list are used as orchard pesticides. Examples are 4300 Cherry Creek Drive South Guthion, Imidan, and Thiodan. Table 12.1 below lists Denver, Colorado 80246-1530 those pesticides where storage amounts and thresh- (303) 692-2977 old spill level require reporting. www.cdphe.state.co.us/oeis/sara/index.html

Table 12.1. Orchard-use pesticides from the EPA List of Extremely Hazardous Substances. Threshold Planning Reportable Quantity Formulated Amounts Con- Chemical Name Quantity (lbs a.i.) (lbs a.i.) taining 1 lb a.i. azinphos-methyl (Guthion) 10 1 2 lbs Guthion 50WP endosulfan (Thiodan) 10 1 2 lbs Thiodan 50WP paraquat (Gramoxone) 10 1 2 qts Gramoxone Super phosmet (Imidan) 10 1 2 lbs Imidan 50WP oxamyl (Vydate) 100 1 2 qts Vydate 2L formetanate (Carzol) 500 1 1.1 lbs Carzol 90W dimethoate (Cygon) 500 10 --- Information

methomyl (Lannate) 500 100 --- Pesticide

Utah-Colorado Tree Fruit Production Guide 173 Chapter 12: Pesticide Information

Pesticide Use with spray chemicals and water quality, and weather conditions further affect their potential use. Thus, Reduced-Risk Pesticides no one adjuvant can or should be used under all conditions. EPA’s Conventional Reduced Risk Pesticide Program registers certain pesticides as “reduced risk.” These Remember that amount and type of the adjuvant are pesticides that pose less risk to human health needed will vary with the hardness and pH of the and the environment than existing conventional water. Use just enough spreader-sticker to break the alternatives. Biological and antimicrobial pesticides surface tension and spread the spray uniformly over are handled through separate registration processes. the leafy surfaces; excessive amounts of surfactants will increase spray runoff. Do not use spreader- Products given the Reduced Risk decision have been compared with existing alternatives currently regis- called for on the label). tered on that use site. These are products that have: stickers with growth regulators (unless specifically low impact on human health Adjusting for Water pH • lower toxicity to non-target organisms (birds, The pH of water used to prepare spray solutions is very important. Water in many locations in Utah • and Colorado is alkaline, ranging in pH from 7.4 to fish,low potentialplants) for groundwater contamination 8.5. The use of alkaline water for spray solution low use rates • preparation can rapidly decompose many insec- • low pest resistance potential ticides and decrease their activity. The following procedure is strongly recommended: • compatibility with Integrated Pest Manage- ment (IPM) practices • 1. Check the pH of your water supply. NOTE: Reduced risk pesticides included in the 2. Read labels to determine whether water pH is spray tables in this guide are under the “Reduced important for that material. risk/Organic” headings within each pest. 3. If necessary, adjust water pH before adding any chemical or pesticide that is sensitive to Use of Adjuvants pH. pH adjusters include Buffercide, Buffer-X, Spray adjuvants are materials added to pesticides in order to enhance their effectiveness. Many insec- ticides and some fungicides are formulated by the 4. Unifilm-B,Apply spray and solutions LI 700 Acidiphactant.as soon as possible after manufacturers with their own adjuvants. Because mixing in the spray tank. Especially avoid of the breadth of conditions growers encounter in leaving mixed spray solutions in the spray tank Utah and Colorado, additional adjuvants may further overnight. enhance the effectiveness of the product. However, select with care, considering all the factors that may Sprayer Calibration affect spray performance. Use of the wrong adjuvant Calibration is important so that the amount of spray for the conditions can decrease product effective- you think you are applying for a known area is ac- ness. Many pesticides will state the type of adjuvant curate. A sprayer may be used one way to spray that can be used. insecticides, and another way to spray herbicides. Calibration should be done with a sprayer that will There are many types of adjuvants, including be used for a particular application, in the same surfactants (ionic or nonionic wetting agents/ manner that the pesticide will be applied. How to spreaders that improve wetting of foliage), stickers, calibrate and calculate how much material to use:

1. and emulsifiers, and agents that buffer, defoam, Each type of adjuvant differs in the way it interacts Spray the water out in the same manner the control drift, penetrate soil, filter UV, and more. Put a known volume (V) of water in the sprayer. Pesticide Pesticide

Information 174 Utah-Colorado Tree Fruit Production Guide Chapter 12: Pesticide Information

pesticide will be applied, then determine the Preparation of Small Spray Quantities area in square feet (A), that was sprayed. Label directions for mixing and applying pesticides 2. To calculate the area in acres that are sprayed come in two general scenarios: rate per volume (usually 100 gallons of water) or rate per area, gallon, and the spray covered 1,075 sq. ft., then (usually acre or 1000 sq. ft.) Mixing directions for by V, divide A by 43,560. For example, if V=1 the area treated by 1 gallon is 1,075÷43,560 or small quantities of pesticide vary with the scenario. 0.025 acre. If your pesticide mixing directions state an amount 3. Next, mix only enough spray to cover the area. of material per 100 gallons, you should adjust the If you need to spray 2,000 square feet and it amount of pesticide to the volume of water you mix. takes 1 gallon to cover 1,075 square feet, divid- Table 12.3 gives mixing rates for label instructions. ing 2,000 by 1,075 gives you the number of If your label instructions state a final spray concen- gallons of spray that should be in the tank. In tration, you do not have to calibrate the sprayer, but this case, 1.86 gallons are needed to cover the you must read the label to know how much spray 2,000 square foot area. material to apply. 4. To calculate the amount of pesticide required for each gallon of spray, multiply the rate per If the pesticide mixing instructions state an ap- acre on the pesticide label by the area you plication rate in an amount per area (usually acre, determined in step two above. In this example but sometimes 1000 sq. ft.), your sprayer must be the area was 0.025 acre. If the rate per acre is calibrated. 6 oz, the amount of pesticide for each gallon is 0.025 × 6, or 0.15 oz/gallon. Use the conver- Densities of solid pesticides vary with the formula- sion factors in Table 12.2 to convert the amount tion and the amount of shaking or settling within into a unit that you can measure with your the package during shipping and in storage. An equipment. electronic scale should be used to ensure the cor- rect weight of the dry product is used. These scales Table 12.2 Conversion factors for weight or volume. are readily available on-line and reasonably priced. wettable powders (W) and dry flowable (DF) Many of these scales measure down to 0.1 gram. The formulations1 use of an electronic scale is essential for the solid 1 lb = 453.6 grams - ables, etc.). 1 oz = 28.4 grams form pesticides (e.g., wettable powders, dry flow liquids Do not use an ordinary teaspoon for measuring ¼ teaspoon (tsp) = 1.25 ml liquids as the common teaspoon varies from 4 to 10 ½ tsp = 2.5 ml ml. Instead, use a graduated medicine spoon. When ¾ tsp = 3.75 ml measuring out small amounts you will need to use 1 tsp = 5 ml a syringe, which are available from your physician, 1 ½ tsp = 7.5 ml veterinary supply, farm supply, or pharmacy. Gradu- 1 tablespoon (tbs) = 15 ml ated spoons and syringes used for a pesticide must 1 gal = 4 qt = 8 pt = 16 c = 128 fl oz = 256 tbs = 768 not be used for anything other than that pesticide. tsp 1 fl. oz. = 2 tbs = 6 tsp = 30 ml 1Dry materials differ in density and render the use of volumetric conversions (to tablespoon/teaspoon equivalents) approximate. Weighing the material provides a more exact conversion. Information Pesticide

Utah-Colorado Tree Fruit Production Guide 175 Chapter 12: Pesticide Information

Table 12.3. Conversion values for preparation of 1, 3, and 5 gallons of spray from the rate per 100 gallons.1 Amount per: Material 100 gal 5 gal 3 gal 1 gal 4 lbs (1,814.3 grams) 90.7 g or 3.19 oz 54.4 g or 1.92 oz 18.1 g or 0.63 oz

Dry: 2 lb (907.2 g) 45.4 g or 1.659 oz 27.2 g or 0.95 oz 9.1 g or 0.32 oz Wettable 1 lb (453.6 g) 22.7 g or 0.79 oz 13.6 g or 0.48 oz 4.5 g or 0.16 oz Powders, & Dry 8 oz. (226.8 g) 11.3 g or 0.39 oz 6.8 g or 0.24 oz 2.3 g or 0.08 oz Flowables 4 oz. (113.4 g) 5.7 g or 0.2 oz 3.4 g or 0.11 oz 1.1 g or 0.04 oz 2 oz. (66.7 g) 2.8 g or 0.06 oz 1.7 g or 0.05 oz 0.6 g or 0.02 oz

192 ml, or 115 ml, or 38.4 ml, or 1 gallon (3,840 ml) 12 tbs + 2 tsp + 2.0 ml 7 tbs + 2 tsp 2 tbs +1 tsp + 0.9 ml 96 ml, or 57.5 ml, or 3 Tbs + 2 19.2 ml, or 2 qt (1,920 ml) 6 tbs + 1 tsp + 1.4 ml ½ tsp 1 tbs+¾ tsp+0.45 ml Liquids: 48 ml, or 28.8 ml, or 9.6 ml, or Liquid or 1 qt (960 ml) Emulsifiable 3 tbs + ½ tsp + 0.5 ml 1 tbs+2 ¾ tsp+0.5 ml ¾ tsp + 1.05 ml Concen- 24 ml, or 14.4 ml, or 4.8 ml, or 1 pint (480 ml) trates, & 1 tbs+1 ¾ tsp+0.25 ml 2 ¾ tsp + 0.65 ml ¾ tsp + 1.05 ml Liquid Flow- ables 1 cup (8 fl oz=16 tbs=240 ml) 12 ml, or 2 ½ tsp 7.2 ml 2.4 ml 4 fluid oz (120 ml) or 8 tbs 6 ml, or 1 tsp + 1.0 ml 3.6 ml 1.2 ml 2 fluid oz (60 ml) or 4 tbs 3 ml, or ½ tsp + 0.5 ml 1.8 ml 0.6 ml 1 fluid ounce (30 ml) or 2 tbs 1.5 ml 0.9 ml 0.3 ml 1 The measurements in tablespoons and teaspoons are approximate. The use of an electronic scale and syringe will be much more accurate.

Understanding the Pesticide Label

The information on the pesticide label represents Product Information the research, development, and registration proce- 1 Product classification dures that a pesticide must undergo before reaching the market, which is paid for by the manufacturer. will state “Restricted Use Pesticide” at the top of The EPA requires a manufacturer to submit data When a pesticide is classified as restricted, the label the front panel. To purchase and apply restricted- from nearly 150 tests prior to the product’s approval for use. through the Utah Department of Agriculture and use pesticides, you must be certified and licensed Food or Colorado Department of Agriculture. Understanding the material you are using, how it is applied, and in what rate, is important for the safety of yourself, others, the host plant, and the environ- 2 Trade Name/Brand Name ment. Also, proper application is required by law. This is the name of the product that the manufac- Described below are the parts of a typical pesticide turer has created. Examples include “Sunspray,” label. “Pounce,” “Warrior,” etc. Pesticide Pesticide

Information 176 Utah-Colorado Tree Fruit Production Guide Chapter 12: Pesticide Information

3 Formulation • emulsifiable concentrate (EC): an oil-based liquid solution plus an

when mixed with emulsifier that, water, forms a milky solution; requires moderate agitation; easy to handle and apply • flowable (or liquid) (F or L): a thick liquid that contains the active ingredient has been imbedded in an inert solid and

powder; requires ground to a fine moderate agitation; easy to handle and apply 5 Active Ingredient • solution (S): the active ingredient mixes The active ingredient, or A.I., is the material that readily with liquid and does not separate is working to kill the target pest. On a label, the • wettable powder (WP): dust-like formulation percentage of the A.I. is provided. The A.I. is usually that does not dissolve in water and must be listed as a common name of the more complicated constantly agitated to remain in suspension chemical name. For example, the chemical name, • soluble powder (SP): a powder formulation 1-((6-Chloro-3-pyridinyl)methyl)-N-nitro-2-imidaz- that readily forms a suspension in water; a rare olidinimine, is also known as imidacloprid. formulation because few pesticide active ingre- dients are soluble in water 6 Other/Inert Ingredients These ingredients do not work to control the target • water dispersible granules (or dry flow- pest directly, but are sometimes added to the prod- ables) (WDG or DF): small granules that, uct to improve effectiveness (as a dissolving agent, - surfactant, etc.) ticles; constant agitation required when mixed with water, disperse to fine par • water soluble packets (WSP): a wettable or 7 Net Contents soluble powder that has been pre-measured into a plastic bag that dissolves in the tank 8 EPA Registration Number water Every product has a unique registration number. This may or may not be on the front panel. 4 Mode of Action This information is sometimes included on a label, 9 Manufacturer’s Address

This is important to know because growers should Information

and provides the pesticide classification number. Pesticide rotate among classes to prevent resistance. This may or may not be on the first panel.

Utah-Colorado Tree Fruit Production Guide 177 Chapter 12: Pesticide Information

Safety and Environmental Information User safety recommendations This section is usually surrounded by a box, and Signal Word 10 includes information on proper washing after Each pesticide label has a “signal word”. handling the pesticide. Danger-Poison: accompanied by a red skull and crossbones and means that the product • Environmental hazards can be fatal, or illness can occur if swallowed, An explanation is provided of potential hazards absorbed, or inhaled. and the precautions needed to prevent injury or Danger: corrosive, and can cause irreversible damage to non-target organisms or to the environ- eye damage or skin injury. ment, especially preventing groundwater contami- • Warning: moderately toxic, and can cause nation. moderate eye or skin irritation. • Physical or chemical hazards Caution: mildly toxic, but can cause slight eye or skin irritation. • Explains hazards for fire, or other. Use Information 11 Keep Out of Reach of Children Warning 14 Directions for Use The front panel of every pesticide label must bear This section usually makes up the bulk of a pesticide this statement. label and always begins with the wording: “It is a violation of federal law to use this product in any 12 First Aid (May or may not be on front manner inconsistent with its labeling.” Products panel) intended for use in agriculture will have an Agricul- tural Use Requirement box included in this section. This section recommends proper antidotes and It will state that the Worker Protection Standard treatment for medical personnel treating a victim. applies to the product. For this reason, always take the pesticide label with you if you need to visit an emergency medical facil- Directions for use include: ity. Products labeled DANGER also bear an 800 tele- phone number that physicians may call for further treatment advice. • the crops to which the product may be applied • the pests that the product targets 13 Precautionary Statements Hazards to Humans and Domestic Animals • amount to use This part of the label includes precautionary • method of application • timing of application exposure, and precautions to be taken to avoid hu- statements indicating specific hazards, routes of man and animal injury, based on the signal word. • pre-harvest interval Protection for mouth, skin, eyes, or lungs are pro- • re-entry interval • PPE requirements for early re-entry avoid acute effects from exposure. vided, and what specific action you need to take to • other limitations 15 Storage and Disposal Personal protective equipment Storage information such as temperature and light requirements, are provided to prevent the break- type of clothing that must be worn during the han- Specific instructions are included regarding the dling and mixing processes. The personal protec- formulations have minimum storage temperature down of the material. Most liquid or flowable tive equipment listed is the minimum protection requirements. This section also explains how to that should be worn while handling the pesticide. deal with the unused portion of the product and the container. Pesticide Pesticide

Information 178 Utah-Colorado Tree Fruit Production Guide Precautionary Statement: Utah State University Extension and Colorado State University and their employees are not responsible for the use, misuse, or damage caused by application or misapplication of products or informa- tion mentioned in this document. All pesticides are labeled with ingredients, instructions, and risks, and not all are registered for edible crops. “Restricted use” pesticides may only be applied by a licensed applicator. The pesticide applicator is legally responsible for proper use. USU and CSU make no endorsement of the products listed in this publication.

Utah State University is committed to providing an environment free from harassment and other forms of illegal discrimination based on race, color, re- ligion, sex, national origin, age (40 and older), disability, and veteran’s status. USU’s policy also prohibits discrimination on the basis of sexual orientation in employment and academic related practices and decisions. Utah State University employees and students cannot, because of race, color, religion, sex, national origin, age, disability, or veteran’s status, refuse to hire; discharge; promote; demote; terminate; discriminate in compensation; or discriminate regarding terms, privileges, or conditions of employment, against any person otherwise qualified. Employees and students also cannot discriminate in the classroom, residence halls, or in on/off campus, USU-sponsored events and activities. This publication is issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Dept. of Ag., Noelle E. Cockett, Vice President for Extension and Agriculture, Utah State University.

Colorado State University, U.S. Department of Agriculture and Colorado counties cooperating. CSU Extension programs are available to all without discrimination. No endorsement of products mentioned is intended nor is criticism implied of products not mentioned.