Caterpillar bonanza continues

July 12, 2019 7:57 AM
Blog Post

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%.

 

Thistle caterpillar.
Thistle caterpillar. Photo by Erin Hodgson. 

Yellowstriped armyworm.
Yellowstriped armyworm. Photo by Erin Hodgson. 

Celery leaftier.
Celery leaftier. Photo by Erin Hodgson. 

Authors: 

Erin Hodgson Associate Professor

Dr. Erin Hodgson started working in the Department of Entomology at Iowa State University in 2009. She is an associate professor with extension and research responsibilities in corn and soybeans. She has a general background in integrated pest management (IPM) for field crops. Dr. Hodgson's curre...