Loopers have become an uncommon pest of cotton due to the use of Bt cotton varieties. Both the cabbage looper and soybean looper may occur. Both are light green and have two pairs of prolegs, which distinguishes them from other caterpillars found in cotton. Looper infestations almost always occur after plants have begun to flower. The caterpillars (larvae) feed on leaves, causing irregularly shaped holes. Looper populations are often held below damaging levels by natural biological control agents.
Scout by estimating the percent of defoliation observed throughout the field. Use a sweep net or drop cloth to confirm the presence of loopers.
|Insecticide (Trade Names)|
|Lb Active Ingredient|
Soybean / Cabbage
|chlorantraniliprole (Prevathon 0.43 SC)||0.067 - 0.09||20 - 29 oz||8 / 9|
|chlorantraniliprole, λ-cyhalothrin (Besiege)||See label||10 - 12.5 oz||8 / 9|
|emamectin benzoate (Denim 0.16)||0.01 - 0.015||8 - 12 oz||9 / 9|
|indoxacarb (Steward 1.25)||0.09 - 0.11||9.2 - 11.3 oz||9 / 9|
|methoxyfenozide (Intrepid 2)||0.06 - 0.16||4 - 10 oz||9 / 9|
|spinetoram (Radiant SC 1)||0.033 - 0.0625||4.25 - 8 oz||8? / 9?|
|spinetoram, methoxyfenozide (Intrepid Edge)||See label||4 - 8 oz||9 / 9|
|spinosad (Blackhawk 36% WDG)||0.056 - 0.072||2.4 - 3.2 oz||9 / 9|
- Plant early maturing varieties and avoid unnecessary insecticide applications that may disrupt populations of natural enemies.
- Bt cotton varieties typically provide good control, and supplemental insecticide applications are rarely needed.
- Insecticide applications can be terminated when cotton has accumulated 600-700 DD60s past NAWF5 (NAWF5 = average of 5 or fewer nodes above a first position white flower).