integrating pest management into high tunnel production

1. Integrating Pest Management into High Tunnel Production Kathy Demchak Penn State University

3. Types of Tunnels Single bay or multi-bay

6. Primary Sought Benefits Extend spring & fall growing seasons (esp. single-bay) Protection from rain (single and multi-bay) And wind (single-bay)

7. Environmental Changes Relative to Field No moisture on foliage from rain or irrigation Placement and amount of water is controlled Higher humidity Warmer air temperatures Mild in winter Can be hot in summer Warmer soil temperatures Lack of soil freezing during winter

8. Effects on Plants Longer growing season – earlier and later yields Generally grow much larger than in field Higher yields Can grow some crops that we couldn’t otherwise due to short growing season or cool temps

9. Effects on Pests No moisture on foliage from rain or irrigation Diseases that need periods of leaf wetness decreased – or not, if ventilation and condensation is a problem, depends on design Some insects (“greenhouse pests”) increase Mites, aphids, whiteflies, thrips

10. Effect on Pests Placement and amount of water is controlled Root rots can be minimized Ants do well in dry areas Higher humidity More powdery mildew

11. Effects on Pests Warmer air temperatures Rapid increase in some pests, esp. 2-spotted spider mites Warmer soil temperatures Lack of soil freezing during winter Some new pests Sowbugs, earwigs, ants Larger problem with crown-borers (?)

12. Other Effects Possibly greater success with biological pest control for insect management

13. Background - at PSU Pesticide-free if possible Emphasis on prevention, biological controls, minimizing pesticide use Non-restricted pesticides only when necessary

14. Pests that are a problem every year, many crops Two-spotted spider mites Western flower thrips (and onion) Aphids (various species) Whiteflies

15. Two-Spotted Spider Mite and Eggs (Leaf Underside)

16. Less consistent Sowbugs Grasshoppers Flea beetles (mustards) Cabbage looper Tomato hornworm Colorado potato beetle (eggplant) Earwigs Crown borer (blackberries)

18. Crown Borer on HT Blackberries

19. Most common disease issues Powdery mildew Viruses (increased numbers of vectors such as aphids and thrips)

20. Powdery mildew

21. Viruses

22. Bottom line Pest complexes more similar to those in greenhouse production than in field

23. IPM in High Tunnels Much information exists on IPM in greenhouses Had a “leg-up” on information Many strategies being tried Good match with high tunnel production

25. Strategies Knowledge What’s there, life cycles Cultural methods (avoidance??) Physical/mechanical Biorational Pesticides “Soft” Conventional

26. Before You Plant – Cultural methods Rotations (multiple high tunnels, moveable high tunnels) Crop choice (avoid eggplant?!) Clean plants (reputable supplier, inspect plants – yours or another source) Weed management

27. Weed management (cont.) Important both inside and outside May be easier inside the tunnel Even a few is too many Maintain a buffer zone Constant – don’t let pests build – they’ll look for replacement food, maintain

28. Once the crop’s in Monitoring Sticky traps – insect specific Scouting

29. Scouting Plants for Insects Weekly Where to look? “Hot Spots” Learn to recognize damage from a distance (hopefully not needed) Be quick but thorough Record releases, chemical applications Take notes; keep from year to year

30. Cultural methods Continue weed control Row covers (lightweight ones for exclusion) – easy to keep on in a tunnel Pruning Removal of pest when practical (hornworms, e.g.)

31. Predators/Parasitoids Ideal as preemptive strategy – start early Not so ideal as cure Expensive May not be able to catch up Learn how to care for them Assoc. of Natural BioControl Producers Some establish in high tunnels or naturally move in Can manage the most common pests

32. Pesticides and Beneficials Impact on predator could be huge Depends on pesticide May need to completely avoid If safe enough, may be of value prior to release Location of use “Hot spots” – maintain safe areas Ask predator supplier

33. Beneficials– not just for insects and mites Hyperparasites Those that compete for same food sources

36. Tomato Hormworm & Tachinid Fly Eggs

37. Ladybug eggs vs. Colorado Potato Beetle eggs

38. Rodent Control!

39. Predators that are returning or appearing Green Lacewing Eggs Aphid parasitizers – Predatory wasps Pearl/bronze shell of aphid Aphidoletes Midge (never released) Orange midge and aphid skeletons Encarsia Formosa Black whitefly eggs

40. Beneficial Plants

41. Pesticides Questions on breakdown under different plastics EPA interpretation of labels for tunnel use Check with individual states for restrictions and rulings Err on side of safety “Stay out of the news”

42. Specific pests

43. Two Spotted Spider Mites Scouting Oldest leaves get the most attention Look for round eggs, besides mites Sticky traps don’t work (don’t fly) Watch for stippling (!!) Insecticidal soap only temporarily Release predators quickly We use a Neoseiulus mix (N. fallacis and N. californicus), others work too Others

44. Aphids Scouting for aphids – Undersides of leaves Curled shoot tips, new leaves a problem Yellow sticky cards Ants (protect aphids), honey dew, sooty mold Concern for viral transmission Ladybugs, green lacewings and predatory midges (Aphidoletes aphidimyza), parasitoid wasps (various spp.) Soft insecticides when necessary

45. Western Flower Thrips Scouting for thrips – broad host range In blossoms Dislodge over white sheet of paper Silvering, streaking of leaves Blue sticky traps more attractive Biological controls if low population Predatory mite (Neiseiulus cucumeris) Minute pirate bug (Orius insidiosus) Soft insecticides

46. Whiteflies Scouting – need to know species Leaf undersides Watch for honeydew, sooty mold Yellow sticky cards Watch for ants (protect whiteflies) Also a concern as a vector of viruses Parasitoid wasps (Encarsia formosa or Eretmocerus eremicus, depending on species of whitefly)

47. Diseases Powdery mildew Cucurbits Don’t grow, or resistant cultivars

48. Sources of Information State guides Assoc. of Natural Biocontrol Producers: http://www.anbp.org