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How to identify it
- Caterpillars are light green with a narrow white line along each side, which fades as they reach full size; newly hatched ones are pale yellow.[1][3][2]
- Full-grown caterpillars are a little over 1 inch to about 1 1/2 inches long.[1][2]
- They loop as they walk, but they have three pairs of prolegs in the middle of the abdomen (four pairs counting the pair at the tail), and they wriggle violently, jump and flop when disturbed.[1][3][4]
- Adults are mottled gray-brown moths about an inch long with a snout projecting in front of the head, triangular in outline at rest.[4]
Look-alikes
| Look-alike | How to tell them apart |
|---|---|
| Cabbage looper | Often confused with the green cloverworm, but loopers have three pairs of prolegs instead of four.[3] |
Where it lives
Occurs from Mexico across the Atlantic Coast states and west to the Great Plains, as well as in eastern Canada; it overwinters in North Carolina.[2][4]
Biology and life cycle
Females lay eggs on both the upper and lower sides of leaves; the caterpillars go through 6 or 7 stages, and most pupate in the soil, though some pupate on the plant.[4]
Missouri reports three generations a year and Purdue two or more; caterpillars are found from summer, or late June in Indiana soybean fields, through fall.[1][3]
Damage and signs
- Young caterpillars skeletonize the underside of leaves and leave the upper surface intact; older ones eat everything but the major veins, giving plants a ragged, hail-damaged look, usually in the upper part of the plant.[3][2]
- Hosts are legumes, mainly soybean and alfalfa, plus beans, cowpeas, peas and clover.[1]
- It rarely reaches damaging levels because parasites and diseases usually keep it in check, and a few caterpillars can even help by attracting natural enemies that also attack worse pests.[3][4][2]
Health risk
It feeds only on plants; none of the sources reports any harm to people or pets.[1][4]
Control
Biological control
Parasitic wasps and a fungal disease often control it naturally; parasitized caterpillars become mummies, so look for them before deciding on any treatment.[3][2]
Pesticides
Treatment is rarely needed; for current thresholds and products, consult your local extension office and follow the label of any product used.[2][4]
Common questions
- What is the green caterpillar that flops around when I touch it?
- A slender green caterpillar with a white side stripe that wriggles and flops violently when disturbed is likely a green cloverworm.[4][3][1]
- Do I need to spray green cloverworms?
- Usually not; natural enemies tend to keep them below damaging levels, and plants such as soybeans can make up for lost leaves.[3][2]
Sources
- University of Missouri Extension, “Caterpillars in Your Yard and Garden (IPM1019), page 20: green cloverworm.” extension.missouri.edu/publications/ipm1019/20 (accessed 2026-10-17)
- Crop Protection Network (multi-state university extension collaboration), “Green Cloverworm in Soybean (published April 10, 2026; C. Pilcher and R. Wright).” cropprotectionnetwork.org/encyclopedia/green-cloverworm-in-soybean (accessed 2026-10-17)
- Purdue University Extension Entomology, “Green Cloverworms (Soybean) (Field Crops IPM).” ag.purdue.edu/department/entm/extension/field-crops-ipm/soybean/green-cloverworms.html (accessed 2026-10-17)
- NC State Extension, “Green Cloverworm (Soybean Insect Factsheets, D. Reisig).” diagnosis.ces.ncsu.edu/soybean/disorder/detail/green-cloverworm (accessed 2026-10-17)
- iNaturalist, “Hypena scabra taxon page (order and family).” www.inaturalist.org/taxa/118513 (accessed 2026-10-06)