Dectes stem borer survey

Similar to last year, we will conduct a survey for dectes stem borer stem tunneling in Illinois over the next several weeks, and are looking for volunteers to help us monitor fields. If you are interested in scouting some of your fields for dectes stem borer, send me an email (nseiter@illinois.edu) and I will provide you our sampling protocol/data sheet. Basically, it involves splitting 25 soybean stems per field between R6 and R8 and counting the number of tunnels and larvae. (This usually takes me right around 30 minutes per field, but individual results may vary). If you’re already assessing your fields for dectes stem borer tunneling, sharing the information with us will help to track its distribution throughout the state, including how and if it is changing over time. If you’ve never looked for dectes stem borer before, consider this an opportunity to familiarize yourself with this insect and help us get some useful information.

In 2021, the most heavily infested fields we observed were in Washington, Jefferson, and Franklin Counties. While we will again focus most of our survey efforts on southern Illinois (where this insect has been observed more frequently in the past), we also hope to get samples from elsewhere in the state – particularly those areas where no-till and conservation tillage are common. Volunteer sampling will complement our own sampling efforts, which are funded by the Illinois Soybean Association. Note also, if you are interested in dectes stem borer and would be willing to let us sample some of your fields, send me an email – I can’t promise I’ll get to every field you send, but we will sample as many as we can before harvest.

Nick Seiter, Field Crop Entomologist | nseiter@illinois.edu | (812) 593-4317