Sampling method
Woollybears are hairy (woolly), yellowish or brown caterpillars up to 2 inches in length. Populations are often overestimated because the larvae and damage are striking. The smaller larvae often are observed feeding in groups on the underside of the leaves, which quickly become skeletonized and die. The larger, showy larvae tend to feed exposed on the upper leaf surfaces. In 2013, scattered populations developed to levels justifying control.
Chemical control
|
Insecticide |
Rate |
|
Alpha-cypermethrin (Fastac EC) |
1.3 to 3.8 fl. oz./acre |
|
Beta-cyfluthrin (Baythroid XL) |
0.0125 to 0.022 lbs. a.i./acre (1.6 to 2.8 fl. oz.) |
|
Bifenthrin plus imidacloprid (Tempest) |
0.08 to 0.095 lb. a.i./acre (5.1 to 6.1 fl. oz./acre) |
|
Carbaryl (Sevin) |
1.5 to 2 lb. a.i./acre |
|
Chlorantraniliprole (Prevathon) |
14.0 to 20.0 fl oz/acre |
|
Chlorpyrifos (numerous products) |
Check label, but generally 1 to 2 pints/acre |
|
Chlorpyrifos plus gamma-cyhalothrin (Cobalt) |
11.0 to 26.0 fl. oz./acre |
|
Cyfluthrin (Tombstone) |
0.025 to 0.044 lb. a.i./acre (1.6 to 2.8 fl. oz./acre) |
|
Deltamethrin (Delta Gold) |
0.018 to 0.022 lb. a.i./acre (1.5 to 1.9 fl. oz.) |
|
Esfenvalerate (Asana XL 0.66) |
0.015 to 0.03 lb. a.i./acre (2.9 to 5.8 fl. oz.) |
|
Gamma-cyhalothrin (Proaxis, Declare) |
0.0075 to 0.0125 lb. a.i./acre (1.92 to 3.20 fl. oz.) (See label for Declare) |
|
Imidacloprid plus cyfluthrin (Leverage) |
2.8 fl. oz./acre |
|
Lambda-cyhalothrin (numerous products) |
0.015 to 0.025 lb. a.i./acre |
|
Lambda-cyhalothrin chlorantraniliprole (Besiege) |
5.0 to 8.0 fl. oz./acre |
|
Lambda-cyhalothrin plus thiamethoxam (Endigo ZC) |
3.5 to 4.0 fl. oz./acre |
|
Methoxyfenozide (Intrepid 2F) |
0.06 to 0.12 lb. a.i./acre (4 to 8 fl. oz) |
|
Permethrin (multiple products) |
0.05 to 0.10 lb. a.i./acre |
|
Spinosad (Blackhawk) |
0.038-0.050 lb. a.i./acre (1.7 to 2.2 oz/acre) |
|
Thiodicarb (Larvin EC) |
0.25 to 0.4 lb. a.i./acre |
|
Zeta-cypermethrin (Mustang MAXX, etc.) |
0.0175 to 0.025 lb. a.i./acre (2.8 to 4.0 fl. oz.) |
|
Zeta-cypermethrin plus bifenthrin (Hero) |
4.0 to 10.3 fl. oz. of product/acre |
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Content authors
Disclaimers
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