The Plant Health Care Toolbox Approach
Shawn Bernick, MS 952-252-0547 [email protected]
Definitions Plant Health Care (PHC) – a comprehensive program to manage the, health, structure, and appearance to plants in the landscape
Integrated Pest Management (IPM) – method of controlling plant pests by combining biological, cultural mechanical, physical, and chemical means Why do we care? Arthopod pests, diseases, and abiotic disorders can alter tree morpholgy or physiological processes in such a way that longterm plant health is negatively affected, or short and/or longterm plant asthetics are negativley affected.
Most landscape pest issues are due to some other fundamental issue:
• Soil Chemistry/Structure – Nutrient Def – Compacted Soils – pH
• Mechanical Damage
Most landscape pest issues are due to some other fundamental issue:
• Inappropriate Planting Site
• Poor Planting Practices
• Environmental Injury • Too Hot • Too Cold • Too Dry • Too Wet
Methods of PHC/Appropriate Response Process
Ball et al: The Appropriate Response Process in PHC,Journal of Arboriculture 25(1): January 1999
Monitor
Diagnose Control
Prevention Set Action Thresholds Action Set Monitor: Gather Information
Site Information
● -When was the landscape established?
● -What is the irrigation schedule?
● -What products have been applied to the plants?
Key Plants
» -Common pest problems
» -Common cultural problems
Key Pests
• Likely tied to key plants Record Observation
Visit Interval and/or Treatment Interval Monitor
Tools
● Hand lense
● Binoculars
● Mallet
● Hand and pole pruner
● Trowel and rake
● Soil sample bags
Monitor Growing Degree Days and Phenology
GDD are a measure of heat accumulation used by horticulturists, gardeners, and farmers to predict plant and animal development rates such as the date that a flower will bloom, or a crop will reach maturity. (https://en.wikipedia.org/wiki/Growing_degree-day)
GDD = (High Temp + Low Temp) - 50ºF 2 10 = (70 + 50) - 50ºF 2 Monitor Growing Degree Days and Phenology
Phenology: is the study of periodic plant and animal life cycle events and how these are influenced by seasonal and interannual variations in climate, as well as habitat factors, such as elevation. (http://en.wikipedia.org/wiki/Phenology) Diagnosis
Host Prevention
How can we Can we change or modify the host? intervene?
Disease
Can we change or modify the environment?
Time Can we change or modify the pathogen? Environment Pathogen Prevention Change the host Selection and breeding for disease resistance
Right Tree Right Place
13 Prevention Modify the environment Many diseases are induced/increased by tree stress
Use of mulch
Alter the conditions to less favorable for pathogens, more favorable to tree (i.e. phytopthora)
14 Prevention Modify the environment soaker hoses: right amount of water, in the right place at the right time. Prevention Healthy trees are happy trees.
Cultural methods • Presction fert • Root enhancement • Root Collar Excavation Control
● Once monitoring, diagnosis, identification, and action thresholds indicate that pest control is required, IPM programs then evaluate the proper control method both for effectiveness and risk.
Control
Plant Health Care Tool Box
Cultural Practices Spray Soil Applications
Tree Injections Selecting Control Measures Practitioner Criteria
Ease of Application
Retreatment Multiple Interval Uses
Client Preference
Safety Profitability
Cost Tree Care Application Techniques
Systemic Applications Non-systemic
Tree Injections Foliar Sprays • Micro-injection • Macro-injection Trunk and Limb Sprays
Soil Applications • Soil Drench • Soil Injection
Basal Systemic Bark Sprays
Control Options Foliar Spray
Advantages: • Tried and True • Quick Results • Economical
Disadvantages: • Coverage • Drift • Large Trees
Control Options Foliar Spray: Site Inappropriate Site
Appropriate Site
Control Options Foliar Spray: Target Appropriate Pest Inappropriate Pest -Pests affecting outer areas of the -Therapeutic treatments for pests plant feeding where spray will not contact them (i.e. under the bark)
Control Options Soil Injection Advantages: • Easy • No Drift • Low Exposure to applicator and environment
Disadvantages: • Dependent on soil moisture and tree physiology • Limited amount of products
Control Options Soil Injection/Drench
Appropriate Site Inappropriate Site -Label Restrictions -Dry sites -Wet sites
Control Options Soil Injection/Drench Appropriate Pest Inappropriate Pest -Most plant damaging -Nothing labeled for fungi in arthropods the crown and not many for bacterial diseases
Control Options Systemic Bark Spray Advantages: • Easy • Little/No Drift
Disadvantages: • Dependent on soil moisture and tree physiology • Very limited amount of products
Control Options Systemic Bark Spray Appropriate Pest Inappropriate Pest -Most plant damaging -Nothing labeled for fungi in arthropods the crown and not many for -Phytopthora diseases bacterial diseases
Control Options Trunk Injection Advantages: • No Drift • Low Exposure to applicator and environment • Product is directly applied into the tree
Disadvantages: • Dependent on soil moisture and tree physiology • Limited amount of products • Takes more time to train • Trunk wounding
Control Options
Trunk Injection Inappropriate Site Appropriate Site
Control Options Trunk Injection Inappropriate Pest Appropriate Pest -No leaf diseases -Many plant damaging arthropods -Some fungal and bacterial wilt diseases -Some fungal canker diseases -Micro-nutrients
Major Insect and Mite Problems in MN
• Magnolia scale • Tent caterpillar • Pine Needle Scale • Webworm • Bronze Birch Borer • Spruce spider mite • Two Lined Chestnut borer • Honeylocust spider mite • Emerald Ash Borer • Rust mites • Japanese Beetle
Soft Scales Armored Scales
• Larger, more convex shells • Flatter, covered a hard • Can be covered in wax secretion • Feed on phloem • Feed deeper into the tissue, • Produce honeydew bypassing the vascular tissue • No honeydew Soft Scales in MN: • Magnolia scale • Spruce Bud Scale • Cottony maple scale • Lecanium scale
Armored scales: • Pine needle scale • Oystershell scale • Scurfy Scale • Golden Pit Scale • Black Pine Leaf Scale Magnolia Scale (soft)
• Eggs produced from mid-summer to fall.
• The non-synchronized crawler hatch period makes timing of spray products challenging.
• Eggs hatch in August through September (2000-2800 GDD)
• Crawlers feed on new growth
• Feeding resumes as leaves emerge the following spring, producing a large amount of honeydew. Pine Needle Scale (armored)
• Timing of symptoms – Late spring to early summer • Symptoms – Sickly, yellow appearing needles – Heavily infested trees can appear silvery from a distance • Signs – Numerous, oval shaped white insects on needles Scale: Soil Applications
Product Timing
Soft Scales Only Spring, Fall
Armored and Spring, Summer, Soft scales Fall
Trunk Spray Option Magnolia Scale Expectations
• Heavy magnolia scale populations will require two years of systemic soil treatments to reduce sooty mold production.
• Hollow brown shells are left behind sticking to the plant for many months. • Check to see if scales are alive by crushing the shell. Live scales will “bleed” when crushed, dead scales will be dry and will not “bleed”.
Magnolia Scale Management • Transtect • Apply Transtect in Early to Mid Summer
• A combination of properly timed sprays and soil applied treatments may be required in the first year of treatment to get high pest infestations under control.
• As scale populations are reduced in following years, consider applying a stand-alone soil treatment of imidacloprid in early spring or dinotefuran in late spring/early summer.
Pine Needle Scale Management
• Transtect – Apply Transtect in Mid to late Spring – 1-3 weeks prior to egg hatch and crawler emergence (277 GDD) in the spring Transtect: Pine Needle Scale
Pine Needle Scale Results 7th June Pine Needle Scale Results 25th June
100 200
90.75
90 180
80 160
70 140 126.5
60 120
50 100
40 80
60
% Mortality of second nymphs instar of second % Mortality 30
20 fascicles 4 Females/ of Adult Number 40 8.5 10 20
0 0 Control 1 Transect Control 1 Transect Control Control
Transect Transect
Transtect 70SG (3.4 g/inch DBH) in 10 qts / water per tree Transtect applied on May 15, 2008 (1 Week After 1st Egg Hatch) Scale: Spray Treatment Effective only on crawlers
Product
Hort Oil (Armored Scales)
Pyriproxyfen (IGR) DISTANCE
Imidacloprid
Dinotefuran Scale: Tree Injection
Product Timing Imidacloprid Spring, Summer, Fall
Acephate Spring, Summer, Fall Bronze Birch Borer
Agrilus anxius on Birch Bronze Birch Borer Hosts
Non-native birch species are most susceptible
• Birch trees tend to prefer cool and moist growing sites
• opportunistic and thrives on weakened or stressed trees
• drought, soil compaction, root injury, other insects
Two lined Chestnut Borer
• Agrilus bilineatus (Weber) • Hosts: maple, oak, hickory, sycamore, tuliptree, willow • Overwinter: larvae; 2 years to complete development • Trees susceptible after drought and other stress events
Robert A. Haack, USDA Forest Service, Bugwood.org Bronze Birch Borer and Two Lined Chestnut Borer: : Soil Application
Product Timing
Imidacloprid Spring, Fall
Dinotefuran Spring, Summer,
Trunk Spray Option Bronze Birch Borer and Two Lined Chestnut Borer: Tree Injection
Product Timing Imidacloprid Spring, Summer, Fall
Emamectin Benzoate Spring and Summer Canopy Evaluation
• Preventive treatments are more effective • If >30% of the tree is showing symptoms saving the tree is more difficult
Cultural Management
• Proper Site Selection
• Cultural Practices • Mulch • Proper water • Reduce or remediate construction injury
Emerald Ash Borer
You want peak amounts of insecticide in the xylem of the tree when eggs hatch and the larvae start to feed
Emamectin Benzoate Lepidoptera Borers Order: Lepidoptera
• Clear wing moths • Banded Ash Clear Wing • Ash/Lilac Borer • Viburnum Borer
Clearwing Monitoring
• Look for frass (sawdust) exuding from bark surface openings or on ground • Look for emerging adults on trunks • Pheromone traps and sticky traps are available for some species Photo by Dr. Dave Nielsen Photo by Dr. Dave Nielsen
D.A. Herms, OSU Banded Ash Clear Wing Borer • Banded Ash Clearwing are a late season insect that emerge in Early August in Mid-Atlantic
• Bark sprays with insecticides on the trunk and lower limbs 10 –14 after first moth capture • Bifenthrin (Bifen XTS) • Permethrin (Tengard)
• Arbormectin Tree Injection treatments
David G. Nielsen, OSU/ OARDC Emamectin Benzoate Controls Banded Ash Clearwing Borer
D.A. Herms, OSU Ash Lilac Borer • Adults emerge in late-April – early-May (active for 4-6 weeks) • One Generation per year
• Bark sprays with insecticides on the trunk and lower limbs 10 –14 after first moth capture • Bifenthrin (Bifen XTS) • Permethrin (Tengard)
• Arbormectin Tree Injection treatments
Viburnum Borer
• Bark spray applications made once adult Viburnum borer males are captured using sticky wing traps • TENGARD- permethrin • Bifen XTS- bifenthrin Caterpillars Problem: Eastern Tent Caterpillar
Host: • Multiple Species: – Cherry – Apple – Crabapple
Notes: • 90-190 GDD
Caterpillars Problem: Fall Webworm
Host: • Multiple species – Pecan – Cherry – Blackwalnut
Notes: • 2 Generations in SE • 1st Gen 1266-1795
Caterpillars
Lepidoptera
Active Product Timing Ingredient Spring – Early Fall (Retreat Acephate 97% 30day Intervals) Spring – Early Acephate 97% Fall (Retreat 30day Intervals) Caterpillars
Untreated Common Landscape Arthropod Pests Treatments Lepidoptera-Spray
Active Ingredient Timing At time of Chlorantraniliprole emergence 18.4%
At time of Spinosad 11.6% emergence At time of Bifenthrin 7.9% emergence At time of Acetamiprid 8.5% emergence
Bacillus At time of thuringiensis emergence Common Landscape Arthropod Pests Spider Mites: Biology Cool Season Mites
Winter Spring Summer Fall Winter
Pop. Over winter as Eggs on Hatch go Temps reach 85°F increases in eggs (mild through larva host bark and greater late summer winters may have stage and or needles population falls – early fall continuous several instars with on set of activity (55°F) cooler temps
Example:spruce spider mite, there can be multiple generations a year.
Susceptible Trees and Plants Mostly needled evergreens
Spruce spider mite http://extension.umd.edu/hgic/spider-mites-trees-and-shrubs Common Landscape Arthropod Pests
Spider Mites: Biology Warm Season Mites
Winter Spring Summer Fall Winter
Female adults over-winter Temps increase (60°F-65°F) mites As temps decrease, females on host bark become active, lay eggs, and begin over winter on host bark or or needles feeding needles
Example: twospotted mite on honeylocust, oak spider mites • Depending upon temperatures eggs can hatch in a few weeks to five days. • There are multiple generations per season.
Susceptible Trees and Plants Many different broad leaf trees and shrubs Common Landscape Arthropod Pests
Rust Mites - pine needle rust mite
http://utahpests.usu.edu/ip m/htm/advisories/landscap e/articleID=9997 Common Landscape Arthropod Pests Treatments
http://extension .udel.edu/orna mentals/page/4 Spidermites - /
Product Active Timing Ingredient Product Active Timing Mineral Oil When mites are Ingredient Hort Oil 98% active Acephate When mites are Abamectin 97.4% active When mites are Lucid + Hort 2% + Mineral Abamectin Spring - Summer active Oil Oil 98% 2% Spiromesifen When mites are Forbid 45.2% active Bifenazate When mites are Floramite SC 22.6% active Insecticidal Insecticidal When mites are Product Active Timing Soap Soap 49% active Ingredient Acephate When mites are 97.4% active Common Arthropod Pests in USDA Zone 7-10
Problem: Japanese Beetles
Host: • Multiple species – Rose – Linden – Crepe Myrtle
Notes: • One generation per year • Adults emerge as linden flowers are dropping • 1029-2154 GDD (adults)
What about Japanese Beetle and Lindens? Old Technology New Solution Major Tree Diseases in MN
Conifers Deciduous • Rhizosphaera needlecast • Apple scab • Sphaeropsis tip blight • Anthracnose • Phomopsis tip blight • Powdery mildew • Dothistroma tip blight • Leaf spots • Lophodermium needlecast • Dutch Elm Disease • Sirococcus shoot blight • Bur Oak Blight • Oak Wilt
Bur Oak Blight Basal root injections can be done at full leaf out.
Encourage homeowner to water before and after to promote uptake and distribution of the fungicide and to prevent phytotoxicity. Treatment: Untreated Treated A basal root flare infusion of Alamo
A spring foliar spray may be necessary to control heavy infections. 10 ml Alamo Untreated Two Lined Chestnut Borer
• Soil Injection or soil drench of – Xytect – Transtect
• Tree Injection – Xytect 10% – Arbormectin Promote Tree Health and Vigor • Proper watering • Mulch • Reduce compaction • Tree growth regulators
Apple Scab Venturia inaequalis
• Hosts: • Malus spp.
• Eradication • Rake and dispose of fallen leaves
• Cultural Practices • Pruning to increase air flow • Proper Mulching • Do not get foliage moist during irrigation
Apple Scab Venturia inaequalis
• Chemical management – Product: • 2 to 3 sprays with systemic fungicide • Myclotect, Systec 1998, Cleary’s 3336 • Landscape applications are aimed at preventing primary inoculum source from damaging tree
– Timing: • leaf expansion • 68 F with continuous leaf moisture for > 6 hrs • reapply 14-21 days
– Expectations: • Applications will assist with management of the disease
Anthracnose Discula spp., Gnomonia spp., Apiognomonia
• Host(s) – Numerous Hosts: • Oak, Ash, Sycamore, Maple, Dogwood
• Eradication • Pruning and removal of cankers (10-12” below canker)
• Cultural – Proper pruning (especially on dogwood) – Mulch – Proper irrigation – Prescription fertilizer, K fertilizer??
Anthracnose (Foliar) Discula spp., Gnomonia spp., Apiognomonia
• Chemical management – Product: • 2 to 3 sprays with systemic fungicide • Myclotect, Systec 1998, Cleary’s 3336 • May be able to due partial tree sprays on large trees
– Timing: • Bud break • 50-55 F • reapply 14-21 days
– Expectations: • Applications will assist with management of the disease • Multiple annual treatments will increase likelihood for success
Infected shoots with dead leaves hanging down are visible in the canopy. Twig canker and close- up of leaf infection along the vein are shown.
Oak anthracnose caused by the fungus Apiognomonia quercina (Discula quercina) Anthracnose of white oak. Lesions are usually on the margins or tips of leaves and are large and blotchy.
Rhizosphaera Needlecast diseases
• Hosts – Rhizosphaera Spruce (Colorado Blue Spruce) – needles to turn purplish brown and fall from the tree – usually from the inside of the tree working out and from the bottom of the tree working up.
• Eradication – Rake and dispose of fallen needles
• Cultural Practices – Improve drainage – Proper irrigation – Thinning – Promote tree health
Rhizosphaera Needlecast diseases
• Chemical Management – Product: • Junction
– Timing: • 2-4 Applications (Areas with longer growing seasons will require more frequent sprays) – ½ candle extension in Late May – Full Extension Late June/Early July
– Expectations: • Difficult disease to control • Requires multiple applications • Applications will assist with control, but must be combined with cultural practices
Cytospora Canker • Hosts – Spruce (Colorado Blue Spruce)
• Eradication – Therapeutic Pruning to remove cankers • dry periods only
• Cultural Practices – Root System Enhancement techniques – Proper mulching – Pruning and selective thinning in windbreaks – Fertilizer applications if warranted by soil tests