1/23/2017

Why are these herbivores eating MY plants? Organic Management It all started long before we got here….

• Vegetable Pests • Vegetable crops: – Adapted to secondary chemicals – ‘early succession’ – Use chemical cues to – Disturbed habitat locate host plants Ruth Hazzard – Rapid, succulent growth – Can only develop on University of Massachusetts Extension – Protected by secondary specific plant group Vegetable Program chemicals – Colonize & reproduce 2013 Beginning Farmer Professional Develoopment – ‘plant families’ rapidly

Insects with wider host range What do these have in common? (multiple crop families)

Life cycle: clues to management Just a few things to know about your pest…. Photo by Jude Boucher • Where and how does it spend the winter? Large Pupal • What plants does it feed on (‘hosts’)? larvae stage is in • When and how does it find the crop? soil • Are there preferences for some varieties or stages? • Which crop stages are damaged? • How, where and when does it reproduce during the summer? Small • How many generations per year? Larvae Adult • What life stages of the insect cause damage? • What life stages are most vulnerable? • What cultural practices protect the crop & reduce the pest? • Are there natural enemies (wild or released) • Are there effective ? What do we need • How do I scout for it? to know about Eggs this insect? • What is the threshold or cue for action?

1 1/23/2017

Things to know about your farm IPM means prevention first: cultural practices • Plant date • Rotation options • Transplants • Row covers • Fallow & field areas nearby? • Mulches • Floral resources for • Other farms nearby? natural enemies • Resources for row • Crop rotation • Fallow periods, cover cover, pesticides, crops sprayers • Tolerant varieties

Photo by M Spellman. IPM means prevention first: Ladybeetles biological control Prey on • Conservation: Aphids, pollen, – Use selective small larvae insecticides Harmonia axyridis 12-spotted ladybeetle Asian multicolored ladybeetle Coleomegilla maculata • Plant floral resources for beneficials – nectar and pollen

Aphidius colemani Aphid Parasitoids Insidious flower bug (similar to Minute pirate bug -- Orius spp.) Tiny wasps insert eggs into aphids Larva grow and pupate inside aphid Feed on aphids, mites, Aphid exoskeleton serves as pupal thrips case Frequently observed in Multiple generations per year sweet corn or wherever prey insects are found.

Aphid ‘mummies’ before and after wasp emerges Photos by A. Cavanagh

2 1/23/2017

Flea beetle life cycle Flea beetles on Brassicas Above ground, on foliage •Overwinter as adult •Lay eggs in spring ADULT •New adults emerge

Photo courtesy of Manitoba midsummer Agriculture and Food •Some may lay more eggs (partial Striped Flea PUP EGG 2nd) Beetle A S

LAR Crucifer Flea Beetle Underground, VA near plant roots

Flea beetle soil dwelling stages: Types of Flea Beetle Damage: ‘Shot-hole Damage’ Tiny Vulnerable to dessication & disturbance • Non-waxy leaves Well-adapted to survival • Feeding on entire surface • Common on bok choi, arugula, mustard, Chinese cabbage.

Types of Flea Beetle Damage: Brassica groups ‘Marginal Damage’ Brassica rapa Brassica oleraceae

Bok Choy • Occurs on waxy leaves • Mainly on Brassica oleracea crops (cabbage, Kale broccoli, etc) • These crops become more waxy when older Brassica napa Brassica juncea

Mustard

Red Russian Kale

3 1/23/2017

Flea beetle preference by species/cultivar, 2004

What Brassica crops and species do flea beetles prefer? 9

8 2004 experiment, UMass Research Farm 7

L_maritima Sweet Alyssum 6 B. oleracea ‘Blue Lagoon’ Cabbage 5 B. oleracea Flash Collards 4

rapa - pac_choirapa -

rapa - komatsunarapa -

junceagw_mustard - ‘Greasy greens’ 3 B. oleracea* (* non-waxy collard) oleraceagreasy_greens - 2 B. oleracea Gai-lan averagebeetles perplant 1

oleraceacollards -

oleraceacabbage - B. rapa Pak Choi allyssum L_maritima-

oleraceagai_lan - 0 B. rapa ‘Summerfest’ Komatsuna Total •The waxy B. oleracea, and the alyssum, had by far the fewest beetles. B. napus ‘Green Wave’ mustard •Greasy greens, non-waxy B. oleracea, had an equal number of beetles as B. Juncea, mustard. •The species with by far the highest beetle counts were the B. rapas, komatsuna and pac choi.

flea beetles’ favorites 1. Brassica rapa 4. Brassica oleraceae Where do they go in winter? Bok Choy

Kale

Average Number of Flea Beetles per sample Overwintering Study Winter 2001-2002 3. Brassica 2. Brassica juncea 30 napa 25

20

Mustard 15

10

average # ofbeetles

5 Red Russian 0 Kale woods shrubby grassy location of sample

Crop Rotation: No rotation means early Fall Brassicas where to plant Spring Brassicas and large Year 1 spring Year 2 Fall Brassicas populations of Brassicas? Year 1 flea beetles

Overwintering site for beetles Overwintering site for beetles

WOODS, ROADS, WOODS, ROADS, HOUSES, FIELDS HOUSES, FIELDS

4 1/23/2017

Rotating spring Mid-season rotation: crop as far as Plant fall Brassicas in a new field to escape newly Fall Brassicas possible from emerged adults Year 1 last fall’s crop Late Brassicas in field 2 delays arrival and reduces Summer adults beetle numbers Very hungry!!! Overwintering site for beetles

Stop feeding, Early Brassicas in field 1 leave the field

WOODS, ROADS, Overwintered adults HOUSES, FIELDS Spring Brassicas hungry!! Year 2

May June July August September October

Bolted Brassica field: incubator for next generation UMass flea beetle trials, 2003-2004 of flea beetles Caryn Andersen et al Weekly sprays on Komatsuna greens (Brassica rapa) Results: • Spinosad had significantly less feeding damage than control • Pyganic was no different from unsprayed control • Row cover was the most effective treatment

Flea beetle on Cabbage Methods, PTC Research Plots, 2004 Abby Seaman, Cornell, 2011

• Crop: Cabbage “Farao F1” • Planting date: 5/23 1 2 4 5 • Application dates: 5/31, 6/7, 6/14 (started as soon as flea beetles arrived) 50’ Sevin 50’ No Spray 50’ Sevin • Evaluation date: 6/20 No Spray Treatment Rate Mean Damage Rating* Entrust 2.5 oz/A 1.7 A Pyganic 5.0 9 oz/A 2.7 B No border (Cabbage only) With border (Komatsuna & Neemix 4.5 10 oz/A 2.5 B Collards around Cabbage) Neemix + Pyganic 10 oz + 9 oz/A 2.7 B Untreated control 2.5 B • Four replications. Plot size: 20’x15’ *Rating 1-5 with 1 = no damage and 5 = plant almost dead • Treatments (insecticides) applied ONLY in the border (randomized). Treatment Mean • Borders and main crop scouted weekly. Control 2.48 a Entrust 1.68 b Neemix 2.48 a Neemix + Pyganic 2.67 a Pyganic 2.73 a

5 1/23/2017

(graph 2) Average Beetle Numbers (graph 1) Average Beetle Numbers

8 7 7 6 6 5 5 Spraye d PTC 4 4 Bordersno Border 3 yes 3 nos 2 yes 2

1 Avg.Beetles perPlant SeasonalAvg. Beetles perPlant 1 0 Border Main 0 Location of Beetles - border or main Border Main crop Location of Beetles - border or main • Unsprayed borders had the highest beetle numbers, regardless of whether or not they crop contained komatsuna. Main crops of plots surrounded by unsprayed borders had the next highest number of beetles. • The komatsuna border had significantly more beetles than anything else. • The sprayed borders and the main crops inside of sprayed borders had the lowest average • There were no differences between main crops, which indicates that the beetle counts. This indicates that spraying the borders alone may be effective at controlling komatsuna did not actually increase the number of beetles in the main crop. flea beetles in the main crop. • It did not, however, lower the number of beetles in the main crop compared with • The presence or absence of komatsuna in the border had no impact on the effectiveness of the border spray. the main crop of the un-bordered plots.

Full Bloom farm trap crop study, 2013 Full Bloom farm trap crop study, 2013

• Brassica rapa, B. juncea as Results: trap crop (mixtures) in border bok choy More beetles in border (early) rows (near likely migration) kale 2 lacinato 2 More beetles in bok choy (later) • Main crop: kale, collard, red russian 2 Spray boy choy & border 2X as often lacinato, red russian border mix Reduced sprays in remaining crop • Preferred ‘sink’ crop (bok kale choy) lacinato Product strategy: • Scout weekly: damage, red russian Use Pyganic if control needed but beetles/plant border mix rain expected Use mix if pressure is high • Thresholds: 1 to 2/plant, 10- road Use Entrust to get 5-7 day residual 25% damage last year's brassicas • Use Pyganic, Entrust, or mix

Management Strategies for Flea Beetles…

1. Escape them: crop rotation between and during the season 2. Starve them: no host crop for a generation 3. Kill them: tillage after harvest, insecticides 4. Exclude them: row cover 5. Grow healthy plants; use transplants 6. Use trap crops and spray those more often

6 1/23/2017

Soil bags Row cover roller

Why has flea beetle grown to be such a serious Eggplant flea beetle pest on organic farms?

Feeds only on Solanaceous crops – tomato, potato, eggplant --- NOT the same species as crucifer flea beetle Similar life cycle: one generation per year, but two periods of adult feeding (May/June and late July/early Aug)

Which organic insecticides work on flea beetle and Flea beetle numbers on sticky card traps

Colorado potato beetle in eggplant? 0.6 0.6 2009 Expt, UMass Crops Research Farm 0.5 0.5 0.4 0.4

0.3 0.3

Plant

Plant 0.2 0.2

0.1 0.1 0 0 Average Flea Beetle Card Count per no pyganic pyganic Average Flea Beetle Card Count per no entrust entrust

0.6

Eggplant (‘Nadia’) 0.5 3 insecticides: Surround, Entrust, Pyganic 0.4 Alone and in mix of 2 or 3 Entrust, kaolin & 0.3 Weekly sprays pyganic all Plant Sample flea beetles on sticky cards, CPB aduls and larvae, 0.2 defoliation significantly reduced 0.1 numbers 0 Average Flea Beetle Card Count per no kaolin kaolin

7 1/23/2017

Flea beetle defoliation on eggplant We have seen growers use with success:

0.25 --Surround alone 0.25

0.2 --Surround mixed with Entrust 0.2

0.15 0.15

Plant

Plant 0.1 0.1

0.05 0.05

0 0

Average Flea Beetle Herbivory per

Average Flea Beetle Herbivory per no entrust entrust no pyganic pyganic

0.3

0.25 Row cover also works Only kaolin had significantly less feeding damage 0.2 great for early season 0.15 Mixtures seem to have an Plant control! additive effect 0.1 0.05

0

Average Flea Beetle Herbivory per no kaolin kaolin

Caterpillars in Brassicas Diamondback moth Photo by Jude Boucher Imported cabbageworm Cross striped cabbageworm • Multiple generations • Adults small, active at night • Small (full grown = ½ inch) • Segmented and pointed Active and wiggly • Feeding – dispersed across leaves Diamondback moth Cabbage Looper Photo by Jude Boucher

Cotesia rubecula, braconid wasp Imported cabbageworm parasite of imported cabbageworm • Over-winters as pupae • 4-5 generations per year Photo by Jude Boucher • Released 1988 • Cabbage butterflies active in by Roy Van Driesche in MA daytime • 2011 survey: • Eggs are single, green or spread yellowish, under leaves throughout • Caterpillars feed first under Northeast and leaves Central US • Large caterpillars move into the head • Parasitism by Cotesia • Fuzzy, sluggish, gray green, rubecula is shown in thin yellow stripe gray and Cotesia glomerata in black. • Numbers increase later in The percentage of the season unparasitized larvae is shown in white.

8 1/23/2017

See the white larva inside caterpillar

Imported • Attacks second instars cabbageworm larvae. The left one is • Kills caterpillars before Cotesia rubecula: parasite parasitizied by an feeding damage introduced in 1990, now well internal parasitoid, • Spins cocoon Cotesia rubecula. established.

Cabbage looper Diamondback moth Photo by Jude Boucher

• Multiple generations • Moths are migratory • Adults small, active at night – do not overwinter in Northeast • Small (full grown = ½ inch) – late-season arrival (July-Sept) • Segmented and pointed Active – Adults plain brown, fly at night and wiggly • Eggs globe-like, single • Feeding – dispersed across leaves • Small larvae feed on underside of leaves

• Large larvae reach 1 ½ - 2 inches Photo by Jude Boucher • Smooth bodied, ‘looping’ habit • Large, ragged feeding holes across the leaf

Scouting for caterpillars in Brassicas Insecticides for caterpillars •Scout weekly •Early feeding damage is easy • Microbials: to spot – Spinosad (Spintor, Entrust) •Look underneath the leaves to find caterpillars when they – Bt kurstaki (Dipel DF, etc.) are small! – Bt aizawi (Xentari ) Check 25 plants across the field

Threshold for leafy greens take action at 15% infestation = 1 catperilllar/plant on 15% of plants

9 1/23/2017

Cross striped cabbageworm Potato leafhopper

Adults migrate north each year. Arrival date in New England: June 6-21 (1991-2005) Eggs laid in plant tissue Range is moving northward Established in Connecticut & MA Nymphs are wingless, fast Eggs laid in cluster moving Caterpillars feed in a group and destroy single plants Controlled by same products as Moth and group larvae photos by Dr L. T. other caterpillars Kok Virginia Tech, Blacksburg, VA

Hopperburn in potato Scouting for potato leafhopper

Small number of adults and nymphs cause damage Nymphs: Plugs vascular system, causes ‘leaf scorch’, then leaf death, Wedge-shaped then plant death. Fast-moving The earlier the infestation, the (sideways more yield loss. movement) Easy to miss. Look for them Adults: shake Catch it early! UNDER the foliage and look leaves for flight Or use sweepnet

Organic management of potato leafhopper Hopperburn on snap beans •Plant tolerant varieties •Kennebec, Green Mountain, Keuka Gold, French Fingerling

•Looks like a disease •Strong growth before PLH arrival •plant early; use green sprouting method •Yield impact is high when leafhoppers •Don’t wait!!: scout often and spray when adults arrive. arrive early (before • Threshold: when adults arrive; 1-2 nymphs per 10 leaves flowering). •Recommended products: Scout by shaking •Pyganic EC 5.0 - - pyrethrin foliage, searching under leaves for •Azera – mix of azadiractin and pyrethrin nymphs •Plan to spray weekly 2- 4 times •Good coverage of canopy

10 1/23/2017

Colorado potato beetle on eggplant and potato Life cycle of Colorado potato beetle (CPB) • Females lay eggs, approx. 300 over 30 days • Larvae hatch from mid June to early July • Pupae develop underground for approx. two weeks • Summer adults emerge in mid to late July • Second generation larvae hatch in late July and August • August: adults leave potatoes for overwintering sites

Beneficial insects have an impact • Adults overwinter near last year's crop, in soil at field Twelve-spotted ladybeetles eat edges. CPB eggs and newly hatched • Adults move into the crop in larvae late May and early June (walk, then fly) Tachinid fly attacks larvae

Carabid beetle feeds on eggs and • Use crop rotation larvae, parasitizes pupae

Twelve spotted ladybeetle eating Colorado potato beetle egges. Photo by Martin Spellman.

Spined soldier bug, Straw mulch reduces CPB Podisus maculiventris numbers and feeding damage on potato --bring in straw --Leave cover crop strips, then mow --No till Photo by M Spellman

Generalist predator Feeds on larvae and eggs Research and photos: Don Weber, USDA-ARS Insect Attacks Colorado Biocontrol Lab potato beetle Beltsville, Maryland [email protected]

Photos by A. Cavanagh

11 1/23/2017

Insecticide for Colorado potato beetle: Colorado potato beetle on eggplant – 2009 Expt Spinosad (Entrust)

• Kills both adults and larvae (all sizes). • Very effective • Resistance is likely to become a problem. • Alternatives? ? – Beauvaria bassiana – Kaolin (Surround) Entrust, Pyganic and Surround all reduced feeding – Pyganic damage – Azera – mix azadiractin+ Only Entrust reduced number of larvae pyrethrin Photo by Jude Boucher

Thrips on onion Summary: Management of CPB Thrips tabaci

Host plants: onion, leek, Avoid colonizing beetles Brassicas, many flowers, Crop rotation weeds, alfalfa, clover, wheat Plant early (green sprouted potatoes) or late (emerge after June 15) Overwinter in residue, host Use trap crop (early planted potato, sprayed) as barrier to entry. plants

Temperatures affect egg-laying, egg hatch and larval growth • Photo by John Sanderson In June, scout at least weekly Lay eggs in epidermis Control larvae before fourth instar, which does 85% of the damage. Nymphs and adults feed in Use spinosad sprays (Entrust, GF-120 Naturalyte, Entrust SC) upper leaves at night Rotation products: Azera (pyganic + azadiractin, higher rates); Scout at base of stems Surround Look for movement, tiny yellow insects

Scouting for thrips: get close up! Thrips injury INJURY: Rasping mouthparts tear epidermis Whitening or scarring = “blast” Twisting of leaves

IMPACT: Plant vigor reduced Smaller bulb size Entry of pathogens

TIMING Most susceptible to yield loss during bulb enlargement stage

12 1/23/2017

Cultural: Thrips management Thrips injury on Brassicas End of season sanitation Start TP from seed Heavy rain/irrigation Scarring of epidermis dries up Plant vigor – fertility, water, weed-free and becomes brown scar Straw mulch? tissue Planting in plastic? Reflective mulch? Reduces vigor and growth Cabbage: reduces Scout! marketability Damage threshold: 30 per plant or 3 per leaf. (too high for organic) May occur on late Brassicas planted near onions – after To use organic sprays effectively, start early onions mature At least two sprays 7-10 days apart: spinosad, kaolin, pyrethrin Spinosad insecticide (Entrust) controls thrips, flea beetle, Spinosad likely most effective and caterpillars Cabbage: resistant cultivars

Striped Cucumber Beetle

• Destroy young seedlings Overwintering sites • Reduce plant growth and yield • Larvae feed on roots • Fruit damage • Vector Erwinia tracheiphila – bacterial wilt Beetles move in from field edges

JUNE: Beetles rapidly spread through fields of young squash… feed on cotyledons Cuke beetle and first true feeding leaves. transmits the bacteria Bacteria block water uptake and cause vines to wilt and die. Plants are most susceptible in early growth stages (< 4 leaves)

13 1/23/2017

Cuke beetle management strategies Transplants are • Crop rotation especially • Row cover – esp . Early summer squash and zucchini – Best protection! important for • Transplants for most cucurbits (DS winter squash, later organic crops cukes) • Healthy plants with vigorous growth: black plastic, raised squash transplants.jpg bed, trickle irrigation, good fertility • Plant early or late (avoid new seedlings in mid June) -- Flexible plant date -- avoid peak pressure & cold soils • Use perimeter trap cropping to protect less attractive -- Avoid soil pests (eg seedcorn maggot, wireworms) cucurbits (winter squash, cukes, summer squash) -- Grow bigger earlier -- withstand pests, earlier harvest -- Get the crop density you want -- Get ahead of weeds

Which organic insecticides work on cuke beetle? Average number of cucumber beetles 2009 Expt, UMass Crops Research Farm 2.5 2.5

2 2

field work and statistics 1.5 1.5

by Andrew Cavanagh 1 1

Umass Extension 0.5 0.5

Average of totalAverage SCB

Average of totalAverage SCB 0 0 no entrust entrust Cucumber (‘Marketmore’) no pyganic pyganic

3 insecticides: Surround, Entrust, Pyganic 3

Kaolin, Entrust & 2.5 Alone and in mix of 2 or 3 Pyganic all 2 Three weekly sprays June 3, 10, 17 significantly reduced 1.5 number of beetles 1 Sample live & dead beetles, defoliation 0.5

Average of totalAverage SCB

0 no kaolin kaolin

• Apply before plants are Defoliation of true leaves colonized by beetles

1.2 • Rate for backpack sprayer: 1 0.9 1 1/2 lb per gallon (1.5 cups) 0.8 0.7 0.8 • Mixing: slurry in bucket; add to 0.6 0.5 0.6 sprayer tank 0.4 0.4 0.3 • Clean nozzles after 0.2 0.2 0.1

Average of defoliation

Average of defoliation 0 0 no entrust entrust no pyganic pyganic

Entrust: no effect 1.4 1.2 Pyganic and Kaolin: 1 0.8

significantly less 0.6

defoliation 0.4

0.2

Average of defoliation Kaolin most effective 0 no kaolin kaolin

14 1/23/2017

Dipping transplants Blue Hubbard or Buttercup trap crop around butternut winter squash Double row near woods No break in the border

Jeremy Barker-Plotkin, Simple Gifts Farm

Average Beetle Pressure 2006 Cucurbita maxima are best for the trap crop 8 A

7

6

5

4 Average of dead Buttercup Squash Blue Hubbard Average of live 3

2

Average per Plant Beetle Count Beetle Plant per Average 1 B B B

0 border main border main

Cinderella Pumpkin Prizewinner Giant Pumpkin PTC Control

Will PTC work in organic crops? Organic insecticide tool box Common name Type of pest targeted Labeled/useful (Trade name) crops • Works best on a large block (not too long and thin) Kaolin Beetles, leafhopper cucurbits, dry beans – Plant main crop to winter squash & pumpkin mix (Surround WP) eggplant – Plant main crop to succession cukes, summer squash inside Spinosad Beetles, caterpillars, thrips many border area (Entrust) • Need an (MORE) effective way to kill beetles in the border Neem Beetles, caterpillars, Vegetables (Azadirect, Ecozin, whiteflies, thrips, aphids – Use spinosad or pyrethrin Neemix etc.) – Hubbard or buttercup attracts beetles even when NOT sprayed Bacillus thuringiensis. caterpillars Leafy, Brassica, – Note: Suction is not effective kurstaki or aizawi fruiting, corn • Use kaolin on main crop as repellent – push / pull. Pyrethrin Leafhoppers, beetles, vegetables • Use crop rotation (PyGanic EC5.0) caterpillars, aphids

Insecticidal soap Mites, aphids, whiteflies vegetables

15 1/23/2017

Organic insecticides- more & newer tools

Common name Type of pest targeted Labeled/useful (Trade name) crops

Clove, Thyme & Soil pests: root maggots, Brassicas (root and Cinnamon Oil seedcorn maggots, stem types), Carrots, (Ecotrol G) wireworms, cutworms Onions, Potato, Corn, spinach, Rosemary Oil Aphids, mites, plant bugs, Vegetables, herbs (Ecotrol EC) thrips spinosad bait (Seduce) Cutworms, earwigs Most vegetables, fruits (other? )

Beauveria bassiana Thrips, caterpillars, aphids, Lettuce, greens, (Mycotrol O, Botanigard) CPB Brassicas, aliums, fruiting crops, potato

Tarnished Plant Bug Nymphs and Adult Overwinter as adults Active early in spring Several generations per year Feed with piercing sucking mouthparts Feed on succulent, young tissue Lay eggs in stem tissue Easy to overlook

Source: University of Georgia, ipmimages.org

TPB Damage Weed hosts • Lambsquarters • Crops that are damaged: • Aster – >40 vegetable crops – Field crops– , alfalfa • Curly dock – Fruits, berries • Fleabane – Flowers • Pigweed • Types of damage: • Ragweed – oviposition or feeding scars • Shepherds purse – leaf death or distortion – tip dieback – fruit distortion – reduced seed production

16 1/23/2017

Damage in early spring arugula (TPB and flea beetle injury) Lettuce: Tarnished plant bug

Romaine lettuce is the type most commonly damaged

TPB Management • Reduce weed habitat around and in the field – Remove overwintering habitat – Remove before buds / flowers form • Use preferred crops (alfalfa, clover) to hold TPB • DO NOT mow it , while target crop is in susceptible stage. • Monitor with white sticky traps, sweep nets, or shaking foliage • Spray when adults first appear, before damage is done – What works? Possibly Pyganic – New product Seduce lists plant bug on label

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