If you have been out in the field checking stand or doing early-season scouting for weeds, diseases, and insects, you might be noticing that insect activity is picking up across the state. We are approximately 200 growing degree days ahead of schedule this spring, which means insect development is happening quickly for insects that overwintered or arrived here with strong storm systems. This does not necessarily warrant any management activities, but be aware that many insects are active right now.
Some of the things we’ve seen or received pictures of (what crop they are found in and whether they overwinter or migrate are in parentheses):
- Bean leaf beetle (soybean; overwinters)
- Thistle caterpillar (soybean; migratory)
- Potato leafhopper (soybean, alfalfa; migratory)
- Aphids (alfalfa; overwinter and migratory)
- White grubs (corn, soybean; overwinters)
- Wireworms (corn, soybean; overwinters)
- Black cutworm (corn; migratory)
- Dingy cutworm (corn; overwinters)
- Bronzed cutworm (forages; overwinters)
- Southern corn rootworm adults (soybean; overwinters)
- Soybean gall midge adults (in emergence cages; overwinters)
- True armyworm (corn; migratory)
- Stalk borer (corn; overwinters)
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- Extension Specialist II
- Professor
- Extension Entomologist Specialist
- ANR Crops Team Leader