Introduction
The Ohio Lep Network is continuing to monitor moth pests across Ohio. As we have begun our seventh week of monitoring, we are happy to begin reports for corn earworm (CEW) monitoring as well as continuing to monitor for European corn borer (ECB) IA and NY populations. As mentioned in our most recent Lep Network newsletter, monitoring for black cutworm (BCW) and true armyworm (AMW) for this season has come to a close. For more resources on these pests and many others, check out our website: https://aginsects.osu.edu
Closing Out Black Cutworm
While we are no longer reporting on black cutworm (BCW), it should be noted that data collected from Van Wert and Hardin Counties last week showed an increase in the average number of BCW moths trapped when compared to previous weeks. Van Wert had an average of 4.8 moths, and Hardin’s average was 3.3.
Chasing Down Corn Earworm
This is our first week monitoring the corn earworm (CEW). Five counties across Ohio monitored for CEW populations using eight total bucket traps. In total, three moths were reported (Figure 1).
Corn earworm is a common corn pest found across Ohio that feeds on corn, tomato, and certain legume fields opening its host to a number of threats, including feeding damage, molds, and an increased threat from birds. The adult moths (Figure 2) are drawn to corn fields that are in the early green silk stage to lay their eggs. Once the eggs hatch, they begin feeding on the ears of corn and threatening the crop (Figure 3). For more information about the Corn Earworm, check out a previous newsletter: https://agcrops.osu.edu/newsletter/corn-newsletter/2019-27/corn-earworm-field-corn-watch-molds
Corn Earworm Moth Map
June 12 – June 18, 2023
Figure 1. Average corn earworm moths (CEW) captured from June 12th to June 18th. The bold 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.
Figure 2. Corn earworm moth coloration. Photo Credit: Mark Dreiling, Bugwood.org
Figure 3. Corn earworm feeding on ear of corn. Photo Credit: Robert J. Bauernfeind, Kansas State University, Bugwood.org
Exploring the European Corn Borer
This is our fifth week monitoring the European corn borer with no variants (IA/NY) being reported from June 12th – June 18th. In total, six counties across Ohio are monitoring for both ECB IA and NY using 16 total wing traps (Figure 4).
The European Corn Borer (ECB) is a common corn pest in Ohio that readily prohibits the proper flow of nutrients within an affected corn stalk. The ECB pest will bore into a stalk of corn (Figure 5), cutting off the nutrient flow and exposing the host plant to a number of problems including stalk breakage, ear drop, and reduction in corn yield. Identifying these pests is the first step to preventing a serious loss in corn crops, see Figure 6 as a reference below. ECB is more commonly a later season moth, so we plan to see an increase in the numbers of both variations in the coming weeks. For more information about ECB please visit: https://aginsects.osu.edu/sites/aginsects/files/imce/ENT_15_14.pdf
European Corn Borer Moth Map
June 12 – June 18, 2023
Figure 4. Average European corn borer moths (ECB) captured from June 12th to June 18th, both IA & NY variants. The bold 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.
Figure 5. European Corn Borer hole in stalk of corn. Photo Credit: Mariusz Sobieski, Bugwood.org
Figure 6. European Corn Borer color variations on a leaf. Photo Credit: Adam Sisson, Iowa State University, Bugwood.org