As we enter early August, we continue to track bollworm populations across the state. Extension personnel across the state have been monitoring insect pests using black lights and pheromone traps for several weeks. Activity data from the Black Light Trap Network shows that populations are, on average, declining relative to peak flights over the past two weeks. However, some locations have increasing counts which suggests that generations are overlapping and/or environmental conditions are contributing to variable development rates.

It will be important to continue monitoring populations because another generation could still impact susceptible cotton, soybeans, and specialty crops in a few weeks.

Find current trap data here.

Practical bollworm management for the remaining season

Bollworms have been a persistent pest of cotton over the last few years, a trend that has been driven by increasing resistance to Bt toxins used in cotton and corn. While 3 toxin cotton (Bollgard 3, TwinLink Plus, and WideStrike 3) provides good protection from caterpillar pests, it is important to continue scouting the crop to ensure unexpected injury does not occur. In a previous article, we cover thresholds needed for bollworm management in 2021 depending on the type of Bt expressed in the variety (article link: Additional Threshold for Bollworm).