Fall Armyworm Populations Have Increased Across Kansas
Rising moth trap counts in September signal potential agricultural concerns for the upcoming spring season.
Updated on Sept. 29, 2026 in Agriculture
Live Poll
Are insect pest threats currently increasing in your community?
Fall armyworms and army cutworms have seen population surges across Kansas this month. Pheromone trap data shows increased activity, particularly in the northwestern region of the state.
Why it matters
Understanding current moth migration patterns is essential for farmers to assess the risk of caterpillar infestations in the coming year. Monitoring these populations helps determine the potential for significant crop damage next spring.
Trap counts of 800 or more moths per area through October could signal major caterpillar activity next spring. Female army cutworm moths are capable of laying 1,000 or more eggs each.
The details
Moths have been migrating into Kansas from their over-summering grounds in the Rocky Mountains. The caterpillars will continue to feed until cooler weather forces them to burrow into the soil for protection.
Timeline
Fall armyworms arrived in Kansas in mid-June 2026.
Pheromone trap counts for armyworms increased in September 2026.
Trap count observations continue through October 2026.
Caterpillars are expected to complete their growth cycle next spring.
Market Landscape
This pest migration pattern follows established protocols outlined in the Alfalfa Insect Pest Management guide. Farmers use these data-driven benchmarks to shift their focus from immediate monitoring to long-term crop protection strategies against regional outbreaks.
Producers should monitor trap counts through October to predict the likelihood of needing control measures for caterpillar activity next spring. Early detection is critical, as controlling smaller caterpillars remains easier than managing larger, more developed populations.
The takeaway
Farmers should continue monitoring pheromone trap levels closely through the end of October to assess spring risks. Taking preemptive action based on trap counts can help mitigate the impact of caterpillar growth cycles on future crop yields.
Further reading
For more on managing pest populations, see the Agriculture section.
More information
Review the full Alfalfa Insect Pest Management guide for comprehensive prevention strategies.
Source note: This article includes information reported by Great Bend Post.
Live Poll
Are insect pest threats currently increasing in your community?
