Insect update for early July 2011
If dry weather continues, there could be a spider mite outbreak. Also, keep checking soybean aphid populations.
My biggest fear at this point, given the lack of rain in the forecast, is a potential spider mite outbreak. I have not seen mites yet, myself, but the weather forecast worries me. Spider mites are one of the more difficult-to-manage soybean pests. Judging the need to treat an infested field can be difficult. Here is our mite scouting brochure to keep handy if dry conditions continue. I would appreciate emailing me with reports of mites if they increase.
Soybean aphids got pummeled by natural enemies and populations dropped quickly in early-planted fields. However, my students found winged aphids in fields planted a little later. An impact of the wide planting window this year may be successive waves of aphid migration, as migrants produced in earlier planted fields move into later-planted fields. Nothing to worry about overall, just keep checking beans to make sure predators are doing their job (an exception as always: potassium deficient areas that are prone to aphid outbreaks).
Western bean cutworms are emerging in dribs and drabs as expected for early July. Japanese beetles also emerged right on time.
Dr. DiFonzo’s work is funded in part by MSU‘s AgBioResearch.