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Green Cloverworm Feeding on Soybeans 07/30/10 2:39:47 PM
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We have found evidence of Green Cloverworm feeding in SouthEast Nebraska this past week. Below is a good reference from UNL regarding identification, scouting and economic thresholds for treatment of this pest.
University of Nebraska–Lincoln
Green Cloverworm Identification:
- Larvae are pale green with one or two white stripes extending down each side of the body.
- They have three pairs of prolegs in the middle of the body.
- Larvae wiggle violently when touched; no other caterpillar damaging soybeans exhibits this behavior.
- Adults are dark brown or black moths with spotted wings.
- Their wingspan is approximately 1 inch.
Life Cycle:
- Overwinter as pupa in leaf litter and crop debris.
- As temperatures warm in the spring, adults emerge and mate.
- Eggs are laid on the underside of leaves and hatch in 4 days
- Larvae develop through 6 instars (stages) and consume most of their food during stages 4-6.
- Mature larvae burrow into the soil or among crop debris to pupate.
- There are usually two generations per year.
Host Range:
- Will feed on alfalfa, bean, clover, cowpea, soybean, strawberry, vetch, as well as many common weeds and other legumes.
Injury & Damage:
- Young larvae feed throughout the soybean plant, but older larvae feed primarily in the upper one-third of the canopy.
- Larvae generally feed in the middle of leaves rather than at the margins.
- Diseases frequently suppress green cloverworm populations, however, this may not occur until after a substantial amount of defoliation has occurred.
Monitoring:
- Sampling should be done with a drop cloth
Management:
- Green cloverworm populations are usually kept in check by a fungal disease.
- Disease development is favored by high humidity and warm temperatures.
- Treat only if defoliation reaches 40% in pre-bloom, 20% during bloom and pod-fill, and 35% from pod-fill to harvest
Contacting Us
UNL Extension
CropWatch Insect Management Team
Phone: (402) 472-8680
Email: tweissling2@unl.edu
© 2010 University of Nebraska–Lincoln | Lincoln, NE 68588 | 402-472-7211 |
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