David Owens, Extension Entomologist, owensd@udel.edu
Corn
Now that corn is tasseling, check field edges, particularly near ditches and small grain fields for the presence of brown stink bug. They concentrate themselves in the leaf axil where the ear is developing. If you see them on the edge, go into the field a bit and keep looking. You might only have an edge population. If you decide to tank-mix a pyrethroid with a fungicide application, bifenthrin is the best on brown stink bug. Otherwise, there are very few insects that would get treated in a timely manner with such an application. Worms will not be affected. Japanese beetles are coming out, but they tend to move in larger numbers once the plants start silking.
Soybean
Green cloverworm and Japanese beetles are active. I have received a couple of calls recently regarding spider mites in soybean. Check field edges, and especially around dry spots where pivots do not reach. Mites may still be largely restricted to the edge and an edge treatment may be all that is necessary. Mite stippling on the upper leaves and abundant mites below (10-20 per leaflet) may warrant a treatment. We have had the best results with Agri-Mek SC and Zeal SC at mid-rates with spreader type adjuvants. Note, these are the only two formulations of the active ingredient labeled for use in soybean.