1. Soybean Insect Identification and Management
Agent Training
June 26-27
NCSU and Plymouth, NC

2. Plant Injury
Chewing
Piercing-sucking

3. Insect Mouthparts

4. Plant Injury
Gall making
Insect Vectors

5. Injury vs. Damage
Injury: harm or destruction on the host plant caused by the pest
Damage: measurable loss of the host that affects the yield quantity, quality or aesthetics

6. Old vs. New Injury
Old
New

7. Economic Injury Level EIL = 𝐶 𝑉𝐼𝐷𝐾
EIL: the lowest number of insects that causes economic damage C = Cost of management per unit area V = market value per unit of product I = Injury units per insect per production unit; expressed as a proportion D = Damage per unit injury K = proportionate reduction in potential injury or damage
EIL = 𝐶 𝑉𝐼𝐷𝐾

8. ET = the number of insects that triggers a management action
Economic Threshold
ET = the number of insects that triggers a management action

9. Corn Earworm/Tobacco Budworm
Thresholds now online! Will lead to Field Crop Entomology Webpage Link Click Soybean Insect Pests Click Corn Earworm Click CEW Threshold Calculator for Soybeans

11. Sampling and Monitoring Methods

12. Direct Sampling
Transect
Random Sampling

13. Seedling Pests Thrips Grasshopper/Katydid Bean Leaf Beetle Cutworm
Threecornered alfalfa hopper
Lesser cornstalk borer

14. Thrips Tobacco thrips predominate after planting, then soybean thrips
Some Eastern flower thrips, very few Western flower thrips

15. White Margined Burrower Beetle

16. Grasshoppers
Most common in reduced till
Adults more difficult to kill

17. Katydid

18. Bean Leaf Beetle

19. Cutworm

20. Threecornered Alfalfa Hopper
Check when beans are less than 10 inches tall
Threshold is one per sweep

21. Threecornered Alfalfa Hopper Injury

22. Stem Borers
Lesser cornstalk borer
Dectes stem borer

23. Lesser Cornstalk Borer
Does this damage seedlings?

24. Dectes Stem Borer

25. Vegetative/Flowering Stage Pests (after seedling stage)
Defoliators
Corn earworm/tobacco budworm
Armyworm complex
Soybean looper (generally late-season)
Green cloverworm (generally NOT a pest)
Velvetbean caterpillar (generally late-season)
Bean leaf beetle
Japanese beetle
Blister beetle
Grape colapsis
Spider mites
Whitefly
Are

26. Corn Earworm/Tobacco Budworm

27. Armyworm Complex

28. Armyworm Complex

29. Soybean Looper

30. Green Cloverworm
Generally NOT a pest

31. Velvetbean Caterpillar
Four pairs
of prolegs

32. Japanese Beetle Beetles often congregate Damage lacy
Usually sub-economic

33. Blister Beetle

34. Grape Colaspis

35. Spider mites

36. Whitefly

37. Defoliator Thresholds
Vegetative stages
30% defoliation
Two weeks prior to bloom and during pod-fill
15% defoliation

38. Vegetative/Flowering Stage Pests (after seedling stage)
Piercing sucking pests
Kudzu bug
Brown stink bug
Green stink bug

39. Kudzu Bug

40. Kudzu Bug

41. Stink Bug Complex

42. Stink Bug Complex

43. Green Stink Bug Nymph

44. Brown Stink Bug Nymph

45. Piercing/sucking like Kudzu bug
However, stink bugs prefer and damage pods

46. Common Beneficial Insects
Ladybird beetle
Lacewings
Minute pirate bug
Bigeyed bug
Nabids
Spined soldier bug
Praying mantis

47. Ladybird Beetle
eggs
adult
larva

48. Common NC ladybird beetles
Asian
pink spotted
pink spotted

49. Green Lacewing
adult
larva
eggs

50. Minute Pirate Bug

51. Bigeyed Bug

52. Nabis (damsel bug)

53. Spined Soldier Bug

54. Praying Mantis

55. Reproductive Stage Pests
Defoliators
Soybean looper
Armyworm complex
Bean leaf beetle
Pod-feeders
Corn earworm/tobacco budworm
Stink bug complex
Stem feeder
kudzu bug

56. Questions?