Today rounds out our 16th week of monitoring for Ohio pests at the Lep Network. This past week, we have seen a sharp decline in WBC numbers and are continuing to see a low average for CEW. Since we are nearing the end of scouting season for WBC, expect this decline to continue and for averages to remain low. Monitoring for WBC will only continue for one more week, while CEW scouting will carry on through August. No counties this past week reported averages higher than 7 meaning that scouting for both pests is less crucial compared to former weeks.
Beginning of Fall Armyworm
This past week, fields in Wooster have been seeing damage that can be tied back to fall armyworm larvae (Figure 1). Less larvae were present this week, so it is assumed that they are pupating/adulting now and another round of larvae may be expected towards the end of August. The Lep network participants are in the process of setting traps and monitoring for FAW adults over the next few weeks.
FAW is an intermittent pest of a variety of plants including: corn, sorghum, small grains, pasture grasses, and forage crops. The fall armyworm is a tropical pest that overwinters in southern parts of the US and makes it way north when clement weather is present. The warm weather this summer has provided a suitable environment for this pest. As discussed in a former OSU article, damage from these pests is expected to become more frequent due to warming climate and the nature of this insect. We plan to follow up with more information on a potential FAW as it progresses. For more information on the fall armyworm, visit one of our previous articles: https://ohioline.osu.edu/factsheet/ent-0093
Figure 1. Fall armyworm larva on corn plant (left); damage to sweet corn field in Wooster. Photo credit: Amy Raudenbush, The Ohio State Department of Entomology, Wooster Campus.
Western Bean Cutworm numbers steady out across the state
This past week was our 7th week monitoring for WBC in Ohio. The statewide average for WBC decreased again from 1.0 during the week ending on July 29th to only 0.25 for the week ending August 4th. Counties with the highest averages are Paulding (5.5), Hancock (2.7) and Lorain (2.0) (Figure 2). As mentioned above, we have leveled out as far as county averages are concerned for the WBC and scouting is not as crucial due to the low state count. If you are still interested in learning how to scout for the WBC, see our previous Lep Monitoring Network Update (#15).
Western bean cutworm moth map
Week 7
July 29th to August 4th, 2024
Figure 2. Average western bean cutworm (WBC) moths captured from July 29th to August 4th. The bold number on the left indicates the average moth count for the week, followed by the standard number on the right which indicates the total number of active traps set up in that county.
Corn Earworm
This is our 9th week monitoring for CEW pests in Ohio. The statewide average for CEW this past week has decreased ever so slightly from 0.18 during the week ending on July 29th to 0.17 for the week ending August 4th. The only counties with any reports are Morgan (3.0), Lucas (1.0) and Auglaize (0.3) (Figure 3). We plan to monitor CEW for ~3 more weeks and expect to see much of the same as far as reports go. To learn more about the corn earworm, check out one of our previous newsletters: https://agcrops.osu.edu/newsletter/corn-newsletter/2019-27/corn-earworm-field-corn-watch-molds
Corn earworm moth map
Week 9
July 29th to August 4th, 2024
Figure 3. Average corn earworm (CEW) moths captured from July 29th to August 4th. The bold number on the left indicates the average moth count for the week, followed by the standard number on the right which indicates the total number of active traps set up in that county.