Doing it Biologically !!!

1. Doing it Biologically !!! Opportunities to use Natural Enemies on Landscape Ornamentals Michael Brownbridge Entomology Research Laboratory University of Vermont

2. Biocontrol success in greenhouses… • controlled environment • closed environment • once released, natural enemies remain on the crop

3. Why are there fewer options for landscape ornamentals ? • environmental conditions more variable, may be sub-optimal • pests can migrate in from surrounding environment • natural enemies will head for the food source – may not be on your plants! Few beneficials with proven efficacy

4. Sanitation IPM Biological Cultural Chemical

5. Pest management is a dynamic process: • Pest outbreaks vary from year to year • Influenced by location, weather • Plant variety • Market • Clientele

6. Why biologicals? Why IPM? • 1. Pesticide stewardship important: • to delay resistance • limited number of new insecticide registrations; FQPA = net loss 2. Health and safety of staff, general public 3. Environmental concerns 4. Difficult to work nr. schools, residential areas

7. Scouting – knowing what’s going on on your plants! • Early detection • More control options • Better control • More cost-effective

9. Bacillus thuringiensis - Bt • Bt kurstaki e.g. Dipel caterpillars • Bt aizawai e.g. Xentari caterpillars • Bt san diego, tenebrionis beetles • elm leaf beetle, imported willow leaf beetle; • not viburnum leaf beetle

10. Viburnum leaf beetle eggs Prune infested twigs Oct-mid April

11. Optimizing Bt efficacy: • Select correct strain • Good spray coverage • Apply early vs. young larvae • More susceptible Less damage, less product, more cost-effective

12. Insect-parasitic nematodes

13. Nematodes for slug control Produced by: Becker-Underwood Sold through: AgBio Inc.

14. HETEROMASK™ Heterorhabditis bacteriophora

15. Steinernema carpocapsae • Effective at 70 – 85° F • Dogwood borer, banded ash clearwing borer, lilac borer, oak borer, peach tree borer (larvae) • Steinernema kushidai • Japanese beetle, oriental beetle (larvae) • Difficult to mass produce • Steinernema feltiae • Fungus gnat larvae in propagation houses • Will work at temps down to 50 ° F

16. Atheta coriaria rove beetle Predator of shore fly and fungus gnat larvae, pupating thrips. Excellent control of shore flies obtained when released at 100 beetles per week per 5000 sq. ft of greenhouse; releases made in early morning or late evening.

17. Nematode use practices: • Active vs. larvae; most effective in containers/pots • Apply to moist soils by drenching • Apply when host larvae present • Soil temperature is important • Compatible with many fungicides and insecticides • www.agnr.umd.edu/users/ipmnet/nemanurs.htm

18. Beauveria bassiana Metarhizium anisopliae ‘Rhizosphere-competent’

19. Ladybeetles • Active release? • Naturally-occurring

20. Green lacewing larvae Chrysoperla carnea feeding on azalea lace bug nymphs lacewing eggs

21. Spider mites • Rapid reproductive rate • Short generation time • Damaging populations build quickly • Pesticide resistance • Broad-spectrum pesticides, resurgence

22. Spider Mite Predators • Phytoseiulus persimilis • good vs. two-spot in greenhouses • does not work well outdoors in cooler regions • Neoseiulus fallacis • wider host range • works outdoors (strawberries, apples) • may overwinter outdoors • use early in infestation cycle • release onto infested plants • www.ent.orst.edu/prattp/plant.html

23. Biocontrol of euonymus scale • Cybocephalus nipponicus • Originally from Korea • Released in NJ on infested euonymus • Established in infestation sites

24. Conservation Biological Control • Conserve naturally-occurring beneficials • Create an environment that is attractive to beneficials • Avoid use of broad-spectrum insecticides Enormous benefits, minimal cost

25. Habitat manipulation to increase biodiversity Flowers attract predators and parasitoids; other insects serve as alternate prey/hosts

26. Use of alternative ground covers • University of Maryland, Paula Shrewsbury www.shrewsburylab.umd.edu • wood mulch on/in place of fabric mat • provides a more favorable habitat for generalist predators • refugia, alterative prey ground beetle larva predatory mites

27. In avocado orchards, mulching increased the incidence and activity of natural enemies and other beneficial arthropods.

28. Using pesticides • Create habitats to maintain natural enemies (refugia) • Flowering plants, ivies, vines • Select and use ‘soft’ or ‘reduced-risk’ pesticides • Short residual activity, narrow host spectrum, IPM • compatible. EPA classification, limited use • restrictions

29. Bio-derived Products Minimum-risk pesticides, exempted from registration requirements – even in NY!!! • E-Rase – Jojoba oil; whitefly control • GC-Mite – cotton seed and clove oils, garlic extract; mites, thrips • Hexycide – rosemary and mineral oil; whiteflies? • Organocide – sesame oil; aphids, mites, powdery mildew Very little efficacy data available on any of the products. May be phytotoxic – test on a limited number of plants before treating a whole crop!

30. Spray Oils and Insecticidal Soaps • Ultra-Fine Spray Oil (Whitmire) • Dormant oils • Synergy Super Fine spray oil emulsion (Griffin) • - micro-emulsion process = remains in suspension for 3 h • PureSpray Foliar 15 (Purespray Green?); Petro Canada • - used in Canada on tree crops, fruits, ornamentals • - pursuing registration in the US • Olympic Insecticidal Soap, M-Pede Broad-spectrum, but short residual; often applied at times of year when little natural enemy activity. Beware of phytotoxicity, esp. on spruces and conifers, after bud-break or in early dormancy.

31. Neonicotinoid Insecticides Similarities: • Expensive • Long residual control • Excellent plant safety, low mammalian toxicity • Systemic or translaminar movement • Active vs. piercing/sucking insects • Variable activity against other pests • Similar modes of action, risk of cross-resistance

32. Neonicotinoid Insecticides Pioneer products: Marathon, Discus, Xenith, Merit New products: • TriStar (Cleary’s) – Acetamiprid spray application only • Safari (Valent) – Dinotefuran very water-soluble, readily translocated • Clutch/Arena (Arvesta) – Clothianidin • Flagship (Syngenta) – Thiamethoxam Various formulations for spray or drench application

33. Other reduced-risk insecticides • Flagship, Endeavor • very effective vs. aphids (sprays), mealy bugs (drench) • Conserve • caterpillars, leaf-feeding beetles, short residual

34. Reduced-risk miticides • TetraSan • translaminar activity vs. spider mites, ovicidal, slow-acting • Floramite • good for early-season infestations, compatible w. predators, selective • Hexygon • restricted use label in NY • Ornamite Limited n. applications per growing season; resistance management

35. Products to avoid: • organophosphates Dursban, Diazinon, Dimethoate • carbamates Sevin, Furadan • pyrethroids Talstar, Tame, Ambush (Pounce) Broad-spectrum, long residual, highly toxic. Many withdrawn for nursery and residential use; restricted use. Pest resurgence, secondary pest outbreaks. www.ent.orst.edu/prattp/pesticides.html for compatibility with N. fallacis

36. Can you do it biologically? • Take active steps to release and preserve natural enemies • Create an environment that conserves and encourages activity • Use reduced-risk pesticides only when necessary in a planned IPM strategy • Will depend on plant species, pest and infestation level, time of year, location and clientele

37. Thanks to: New England Grows Paula Shrewsbury, Univ. Maryland Carol Glenister, IPM Labs, Locke, NY Dan Gilrein, Cornell Univ. Cooperative Extension This presentation is available for download on our website: www.uvm.edu/~entlab Click on ‘Recent Publications’