The Michigan Soybean Committee is urging growers to scout their fields after Dectes stem borer was confirmed in Mid-Michigan soybeans last month.

Mark Seamon, research director for the Michigan Soybean Committee, told Brownfield the pest was detected in August. "This is normally a pest of the southern U.S. or mid part of the country, and this year we found it way" north of its typical range, Seamon said.

The confirmation marks a geographic shift for an insect that growers in Michigan have not historically had to manage. Hollow soybean plants are the telltale sign of infestation, and the committee wants farmers checking fields now rather than after harvest reveals the damage.

Dectes stem borer larvae tunnel inside soybean stems, hollowing them out as they feed. The result is weakened plants that can lodge, complicating harvest and adding to losses at a time when growers are already managing tight margins on input costs and basis.

Seamon's advisory is the second time this season the state's soybean checkoff has flagged unusual pest pressure, and it comes as growers weigh whether the insect will persist in the region or whether this year's detection reflects an isolated northward push.

The Michigan Soybean Committee is not waiting for that answer. Its guidance is straightforward: walk fields, split suspect stems, and confirm what is inside before assuming drought or disease is to blame for hollow stalks.

For growers, the immediate cost of scouting is time. The cost of not scouting could be measured at the combine, where lodged, hollow-stemmed plants translate directly into header losses and slower harvest speeds.

Seamon and the committee are expected to track whether the borer overwinters in Michigan, a question that will shape management recommendations and potential insecticide or cultural-control economics for the 2025 season.