Lettuce seed-Armyworm and looper

Includes

Armyworms

Armyworm (Pseudaletia unipuncta)
Beet armyworm (Spodoptera exigua)

Loopers

Alfalfa looper (Autographa californica)
Cabbage looper (Trichoplusia ni)

Pest description and crop damage Loopers are green, smooth-skinned, and usually have a narrow stripe along each side. Looper caterpillars can be distinguished from other common caterpillars by their distinctive looping movement, in which they arch the middle portion of their body to bring the hind legs forward to meet the front legs. Larvae feed on leaves, causing ragged-edged holes in the leaf and on the leaf margins. They can cause severe defoliation. Adults are brownish moths with distinctive figures on the front wings.

Management-chemical control

Begin applications at first sign of infestation. Multiple applications with thorough coverage are necessary for effective control.

Armyworms

  • azadirachtin (Neemix 4.5) at 4 to 16 fl oz/a (0.012 to 0.049 lb ai/a). PHI 0 days. REI 4 hr. This botanical pesticide acts slowly. Spray early-well before harvest-and check for effect. Apply every 7 to 10 days as needed. Some formulations are OMRI-listed for organic production.

Loopers

  • azadirachtin (Neemix 4.5) at 7 to 16 fl oz/a (0.021 to 0.049 lb ai/a). REI 4 hr. PHI 0 days. This botanical pesticide acts slowly. Spray early-well before harvest-and check for effect. Apply every 7 to 10 days as needed. Some formulations are OMRI-listed for organic production.