David Owens, Extension Entomologist, owensd@udel.edu
Soybean
Scout stand establishment in soybean to make sure no unexpected stand reducing pests are active. Defoliator activity is normal and unlikely to cause issues at this time. We visited one field that had a fair number of bean leafroller present. Several years ago, we had strip trials on producer fields in which a pyrethroid was added to a or left out of a herbicide application. In no instance did it result in a yield response. This prophylactic tank mix is one that you can leave out.
Sorghum
Scout seedling sorghum for defoliation and stand loss, particularly in no-till or reduce- till fields. Slugs and grasshoppers have been known to cause problems in the past.
Alfalfa
Continue scouting alfalfa for potato leafhopper. This insect is now active in Sussex County. Leafhopper threshold tables can be found at https://www.udel.edu/content/dam/udelImages/canr/pdfs/extension/sustainable-agriculture/pest-management/Insect_Control_in_Alfalfa_-2023.pdf. Please note that the crop values may not reflect prices you receive, and if that is the case, you will need to use some judgement on adjusting thresholds appropriately. Leafhoppers cause hopperburn, but yield is reduced before hopperburn is evident.