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Lep Monitoring Network Update #3 – Trap Counts for BCW, AMW and ECB-IA

The Ohio LEP Network is continuing to monitor moth pests across Ohio. For our third week of monitoring, we are reporting the numbers for black cutworm (BCW), true armyworm (AMW), and European corn borer (ECB) IA & NY moths across Ohio. These insects’ larval stages are common pests in Ohio for crops and can cause problems for farmers. If you are looking for more resources on these pests, check out our website: https://aginsects.osu.edu/

Beginning with Black Cutworms

Black cutworms are an early season pest that migrate from southern regions into Ohio as temperatures increase and can cause various issues in crop emergence, and have been our most significant pest this week. Black Cutworms can be identified by a dagger-like marking on their wings (Figure 1). Over the past week, 10 counties have monitored for these moths using over 30 wing traps (Figure 2). Over the past three weeks, we have seen a slight increase in the presence of reported BCW adult moths. From May 15th to May 21st, Hardin, Muskingum, and Wayne counties all experienced high BCW moth numbers (11.6, 10.5, and 8 moths, respectively). The county that had the most moths caught in just one trap was Hardin county, with 19 moths in one trap. Counites with high trap numbers should continue to monitor for BCW larvae after corn is planted, with particular attention to fields with broadleaf weeds such as chickweed and purple nettles, as these are prime sources of food for BCW. For more information about BCW please visit: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_35_14%20BCW.pdf

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Figure 1. Black cutworm moth (BCW) featuring a distinct dagger shaped marking on the forewing (circled in yellow). Photo Credit: Curtis Young. 

Black Cutworm Moth Map

May 15 - 21, 2023

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Figure 2. Average black cutworm moths captured from May 15th to May 21st. The bolded number on the left indicates the average number of moths captured. The second number on the right indicates the number of traps monitored in each county.

Tackling the True Armyworm

We have entered our third week of monitoring for the true armyworm (AMW). These moths are similar to BCW, as they do not overwinter in Ohio, and migrate from southern regions in April and May. These moths are attracted to fields with grasses, winter wheat, barley, and rye cover crops. AMW are a light tan moth with a white dot near the bottom of both wings (Figure 3). From May 15th to May 21st, 11 counties across Ohio monitored for AMW, with 32 total wing traps being set (Figure 4). Van Wert county was the only county to report a larger amount of AMW, with an average of 10.5 moths per trap, and found 21 moths in one trap. All other monitoring counties indicated average moths below 5 moths.

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Figure 3. True armyworm moth displaying the light tan color, and white dot on wings (circled in yellow). Photo Credit: Kylie Harbert.

True Armyworm Moth Map

May 15 - 21, 2023

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Figure 4. Average true armyworm moths captured from May 15th to May 21st. The bolded number on the left indicates the average number of moths captured. The second number on the right indicates the number of traps monitored in each county.

Encounters with the European Corn Borer

The European Corn Borer (ECB) is a common corn pest in Ohio that bores into corn stalks which causes disrupts the flow of nutrients in the corn stalks; which can increase corn stalk disease and stalk breakage, resulting in reduced corn yield. Unlike BCW and AMW, European corn borers overwinter in Ohio in corn stalks, and then emerge as moths in the springtime. These moths then deposit eggs on the underside of corn leaves, where the larvae will then hatch and feed on the corn foliage, before entering the stalk. The ECB moth is a white, with a darker head and body area (Figure 5).  There are various types of ECB, and we monitor for the IA and NY variations. However, this first week of monitoring, only ECB-IA variation was reported.  Our first week of monitoring was May 15th through May 21st, with five counties monitoring for ECB. The only county to report ECB-IA, was Hardin County, with an average of 2 moths per trap (Figure 6). For more detailed information about the ECB please visit: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_15_14.pdf

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Figure 5. European corn borer moth captured on a wing trap. Photo Credit: Suranga Basnagala. 

European Corn Borer Moth Map

May 15 - 21, 2023

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Figure 6. Average European corn borer (IA) moths captured from May 15th to May 21st. The bolded number on the left indicates the average number of moths captured. The second number on the right indicates the number of traps monitored in each county. No ECB-NY were reported over the previous week.

 

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.