Moth trapping update #2

May 13, 2019 4:21 PM
Blog Post

This week we begin Week 7 of moth trapping in Iowa. Significant captures of black cutworm (BCW) have occurred in several counties during weeks 3-6 of trapping (bold and * in Table 1). Significant captures occur when 8 or more BCW moths are caught in a wing-style pheromone trap over 2 nights. Another type of trap used to monitor BCW activity is a bucket trap. This type of trap tends to capture more moths, but determinations about significant flights are not made in our table because a reliable threshold does not exist yet.

Trapping data for BCW are used to estimate cutting dates for corn when significant flights are reported. Since significant flights have occurred in some areas, estimated cutting dates were posted on ICM News. No thresholds exist for true armyworm (TAW) to predict their activity in fields. We continue to monitor TAW (Table 2) to detect when they are present in a particular area and help guide scouting activities for farmers.

BCW captures
Table 1. Black cutworm moth captures.

TAW captures
Table 2. True armyworm moth captures.


Surrounding states also monitor and report findings of BCW and TAW. If you are near the state borders, it may be beneficial to check these resources periodically. Some state resources are listed below, but others may be available online soon:


Ashley Dean Agriculture and Natural Resources Extension Specialist II

Ashley is an education extension specialist for field crop entomology at Iowa State University. She coordinates the Iowa Moth Trapping Network, the Regional Corn Rootworm Monitoring Network, and the Iowa Pest Alert Network. She also develops educational resources for field crop pests in Iowa and ...

Adam Sisson Extension Specialist

AdamĀ SissonĀ is an extension specialist with the Iowa State University Integrated Pest Management (IPM) program and a Certified Crop Adviser. Sisson focuses on the development of publications and other educational resources for farmers, agribusi...

Erin Hodgson Professor

Dr. Erin Hodgson started working in the Department of Entomology, now the Department of Plant Pathology, Entomology, and Microbiology, at Iowa State University in 2009. She is a professor with extension and research responsibilities in corn and soybeans. She has a general background in integrated...