The garden webworm, a common webworm, is slender and green with three dark spots arranged in a triangle on the sides of each body segment. Each spot supports at least one hair. Larvae skeletonize the foliage in the protected, webbed area. If disturbed, larvae move backward rapidly. Peak damage occurs July through August with multiple generations possible. The edges of some soybean fields in northeast Kansas became infested during 2001 with high numbers of webworms moving out of harvested alfalfa fields. Many fields in SE and central Kansas required treatment in 2009, and again in 2010.
This content may not be suitable for states other than Kansas.
|
Insecticide |
Rate |
|
Alpha-cypermethrin (Fastac EC) |
2.8 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) |
1.0 to 1.5 lb. a.i./acre |
|
Chlorpyrifos plus gamma-cyhalothrin (Cobalt) |
11.0 to 26.0 fl. oz. of product/acre |
|
Chlorpyrifos plus zeta-cypermethrin (Stallion) |
5.0 to 11.75 fl. oz./acre |
|
Cyfluthrin (Tombstone) |
0.025 to 0.044 lb. a.i./acre (1.6 to 2.8 fl. oz.) |
|
Deltamethrin (Delta Gold) |
0.018 to 0.022 lb. a.i./acre (1.5 to 1.9 fl. oz.) |
|
Gamma-cyhalothrin (Proaxis, Declare) |
0.0125 to 0.015 lb. a.i./acre (3.2 to 3.84 fl. oz.) (See label for Declare) |
|
Lambda-cyhalothrin (numerous products) |
0.025 to 0.030 lb. a.i./acre |
|
Lambda-cyhalothrin chlorantraniliprole (Besiege) |
8.0 to 10.0 fl. oz./acre |
|
Lambda-cyhalothrin plus thiamethoxam (Endigo ZC) |
4.0 to 4.5 fl. oz./acre |
|
Permethrin (multiple products) |
0.1 to 0.2 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 |