By Scout Nelson
As the 2026 harvest season moves forward in Kansas, farmers are being encouraged to look beyond current yields and focus on weed issues that could affect next year’s crops. According to Kansas State University (K-State) weed specialist Sarah Ganske, harvest is an ideal time to assess the effectiveness of weed control programs and identify areas that may need additional attention.
Ganske, a weed scientist with K-State Research and Extension, advises growers to use time in combines and grain carts to scout for weed “escapes,” or plants that survived this season’s control efforts. Identifying these weeds can help producers anticipate future weed pressure and make better management decisions.
“We often don’t think about weed management in the fall,” Ganske said. “But actually, it’s an important part of the cycle of having good weed management programs across all your acres.”
Harvest scouting can reveal field patterns that may not have been noticeable earlier in the growing season. Observing where weeds persist helps farmers determine which species are causing problems and whether changes to herbicide programs or other management practices are needed.
“We can be on the lookout for areas where we had weed escapes in the current season, because that is going to tell us where we can expect weed problems in the future,” Ganske said.
Identifying surviving weed species can also help detect potential herbicide resistance. The information gathered during harvest may guide decisions on integrated weed management strategies, including the use of fall-planted cover crops such as cereal rye.
Among the most challenging weeds in Kansas fields are Palmer amaranth and waterhemp, both pigweed species. Ganske also highlighted morning glories, velvetleaf, and hophornbeam copperleaf, which has become a growing concern in corn production because of its late-season emergence.
Weed escapes are often found in low-lying areas where crops are less competitive, along heavily trafficked headlands, and near fence rows. Recognizing these patterns can help growers determine whether zone-specific weed management practices would be more effective than treating entire fields uniformly.
Changes in the size or location of weed patches should be monitored closely, as they may signal developing problems. Farmers should pay particular attention to patches that appear unexpectedly or spread beyond their usual boundaries.
In addition to scouting, Ganske stressed the importance of preventing weed seed movement between fields during harvest. Harvesting heavily infested fields last and thoroughly cleaning equipment before moving to another field can significantly reduce the spread of weed seeds.
Farmers can further limit seed movement by avoiding heavily infested patches when possible and regularly cleaning combines, grain carts, tillage tools, and planting equipment. Rain delays can provide a good opportunity for maintenance and deep cleaning.
Through careful fall scouting and proper equipment sanitation, growers can reduce future weed pressure, improve long-term weed management, and protect crop productivity in the seasons ahead.
Photo Credit: kansas-state-university
Categories: Kansas, Crops, Corn, Harvesting