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Agronomic Crops Network

Ohio State University Extension

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Lep Monitoring Network – Black Cutworm and True Armyworm # 6

We are in our sixth week of monitoring for black cutworm (BCW) and true armyworm (AMW) across Ohio. Despite our cold, rainy weather last week, both BCW and AMW numbers remained high in some counties. This is our final week of monitoring BCW and AMW, and at the end of this week, we will switch our traps over to corn earworm (CEW) and Western bean cutworm (WBC) for early June. Read below for more specific county information. 

Black cutworm

Black cutworm numbers have mostly reduced statewide, with only Muskingum and Morgan counties reporting high trap numbers. Over the past week, our team has monitored 47 traps in 18 counties. Our overall statewide average was down this past week to 4.3 (from 7.5 last week). We recommend monitoring fields until plants reach the V6 growth stage, especially in counties that have had averages of 7 moths or more per week. This week, those counties are Muskingum and Morgan (Figure 1).

For more information on how to scout BCW, please visit: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_35_14 BCW.pdf

Black Cutworm Moth Map

Week 6

May 26th – June 1st, 2025

Figure 1. Average black cutworm (BCW) moths captured from May 26th to June 1st. The bold number on the left indicates the average moth count for the week, followed by the standard number which indicates the total traps set up in that county.

True Armyworm

We also monitored 47 traps in 18 counties for AMW moths (Figure 2). We are still seeing AMW, but in fewer counties across Ohio compared to BCW. However, our overall statewide average did increase this week to 4.3 moths (from last week’s average of 3.0). Similar to last week, only 3 counties reported an average of 7 or more moths: Muskingum, Van Wert, and Wood (different counties than last week).

True Armyworm Moth Map

Week 6

May 26th – June 1st, 2025

Figure 2. Average true armyworm (AMW) moths captured from May 26th to June 1st. The bold number indicates the average moth count for the week, followed by the standard deviation, which indicates the total traps set up in that county.​​​​​​​

Crop Observation and Recommendation Network

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.