Soybean stem borer
scouted Aug. 29, 2025
- Scientific Name
- Dectes texanus
- Background
- Soybeans in Pamlico County were being scouted at the R5 growth stage, and it was observed that the leaves were looking leathery without the regular bronzing. Initially, the grower thought it was a nutrient deficiency and sent in a tissue sample, and every level came back at sufficient levels or higher. Then it started to spread across the field. The grower would like to rule out salt damage from Erin, so a sample was submitted to the PDIC for diagnosis.
- Conclusion
- The issue was identified as Dectes stem borer, also known as soybean stem borer. Soybean stem borers have one generation a year and are active from May through early October. It usually causes indirect yield loss due to lodging or an interaction with other negative environmental conditions, such as drought. These insects are usually more abundant in field edges near weeds or fields adjacent to last year's soybeans. There is no economic threshold for it, but good cultural practices and timely harvest can limit its impacts.
- Resources
