After visiting several ISU Research and Demonstration Farms this week, it was evident the abundance and diversity of caterpillars in soybean is ongoing. These species represented several insect families. We easily found 8 species while looking at and sweeping early-reproductive soybean. Of course, thistle caterpillars were easy to find, but the interesting part is we saw a range of ages – from small to big caterpillars. I think it is a combination of first and second generation here in Iowa. We also saw green cloverworm, soybean looper, and alfalfa caterpillar sprinkled throughout the small plots. Although not a big surprise, we found a yellowstriped armyworm, true armyworm, and black cutworm in very low numbers, too. One rarely-seen species that happened to be out in strong numbers was celery leaftier. It builds a webbed nest similar to thistle caterpillar. Overall, populations were low and well under the defoliation threshold of 20%.
Erin Hodgson Professor
Dr. Erin Hodgson started working in the Department of Entomology, now the Department of Plant Pathology, Entomology, and Microbiology, at Iowa State University in 2009. She is a professor with extension and research responsibilities in corn and soybeans. She has a general background in integrated...
Ashley Dean Agriculture and Natural Resources Extension Specialist II
Ashley is an education extension specialist for field crop entomology at Iowa State University. She coordinates the Iowa Moth Trapping Network, the Regional Corn Rootworm Monitoring Network, and the Iowa Pest Alert Network. She also develops educational resources for field crop pests in Iowa and ...