By: Andy Michel, Mark Sulc, Curtis Young, CCA, Kelley Tillmon
Potato leafhopper (PLH) adults arrived in Ohio during the last week of June and the first week of July. Since then, the eggs have hatched and we are now seeing late-stage nymphs and adults infesting alfalfa fields. A few fields are showing the typical “hopper burn”, which is a triangular yellowing from the center of the leaf to the leaf margin. The more mature the crop of alfalfa is since the last cutting, the more the hopper burn symptoms will be showing. Hopper burn will also become more pronounced in areas of the state that are short on rain or are predicted to become drier because the alfalfa will not be able to outgrow the feeding activity of PLH. Scouting now and making appropriate management decisions based on the scouting can help avoid serious damage to the crop. Continue reading
Adult red-headed flea beetle (P. Beauzay, NDSU)
By Kelley Tilmon, Andy Michel
As the summer progresses we are receiving reports of insect problems often encouraged by hot, dry weather. Last week we reported on spider mites and especially if you are in an area of continued dry weather we recommend scouting your soybeans and corn https://agcrops.osu.edu/newsletter/corn-newsletter/2020-22/watch-spider-mites-dry-areas .
Some areas are also reporting increases in young grasshoppers in soybeans, another insect favored by dry weather. Grasshoppers of often start on field edges so early scouting may allow for edge treatment. Japanese beetles are another common defoliator of soybean that are starting to appear. Both of these pests fall into a general defoliation measurement, and we recommend treatment if defoliation is approaching 20% on the majority of plants in post-flowering beans. Download our guide to estimating defoliation in soybean at https://aginsects.osu.edu/sites/aginsects/files/imce/Leaf%20Defoliators%20PDF_0.pdf Continue reading