Soybean fields in southwest Iowa hit by sudden death syndrome will lose 5% to 10% of yield this season, and thistles are cutting pod counts in Indiana fields — two developments growers can still act on, or at least account for, as a wet September stalls harvest across the Midwest.

In the Soybean Watch field south of Indianapolis, thistles visibly damaged neighboring soybean plants even after in-season control measures. Steve Gauck, regional agronomy manager for Beck's, pulled plants adjacent to the thistle patch and found the evidence directly.

"You can clearly see the effect these thistles had on the neighboring soybean plants," Gauck said. "The nodes on these plants are spaced far apart, and the pod load is noticeably less than other plants in this field."

Gauck said thistles are making a comeback after roughly 20 years of decline in the weed seed bank. He attributes the resurgence partly to the shift to no-till, but more to changing herbicide programs.

"When you're focusing on controlling other weeds, then naturally, the changing herbicide offerings will be focused less on weeds like thistles," he said. "These shifts in herbicides are ultimately changing the weed spectrum."

The control window opens after harvest. Gauck recommends a fall burndown on the hardest-hit fields, and with thistles specifically, a residual herbicide for longer-lasting control. The choice comes down to objective.

"Do you want to just kill what's up above the ground, or do you want to target that taproot?" he said.

Nighttime temperatures must stay above 50 degrees F for optimal control, so the effective window after harvest may be short depending on location.

"The best time to control these weeds is in the fall," Gauck said. "Take advantage of this timing to set next year's crop up for success."

Rains stall a promising harvest

Combines were rolling across the Midwest with early yields sparking excitement before September rains hit the pause button. Low pest and disease pressure in many regions, paired with timely rains, had set up a successful crop. Now growers wait.

Illinois. Matt Montgomery, Beck's agronomy education lead, reported early harvest results as positive enough that many growers wonder what yields might have been without the week of 90-to-100-degree F temperatures that closed out August. That late heat appears linked to odd in-field observations: beans occasionally sprouting within the pod, and green stems persisting in random patterns — possibly because heat capped pod count, then late rain drove photosynthate into stems with limited pods to fill it.

Standability issues have been occasional but not epidemic, and most accompanied satisfactory yields.

Montgomery's in-season red crown rot trials showed consistent varietal differences matching last year's patterns, and the seed treatment results were decisive. Seed treatment is now a critical component of RCR management paired with varietal tolerance, he said. Within the succinate dehydrogenase inhibitor fungicide family, cyclobutrifluram provided exceptional suppression and now sets the standard for RCR management.

Looking toward 2027, Montgomery flagged diversifying soybean cyst nematode management with Peking-type resistance and seed treatments, reevaluating soybean fungicide return on investment, weed management concerns, and micronutrient package exploration. High input costs, he noted, continue to temper the positives.

Iowa. Nate Meyer, Beck's field agronomist in southwest Iowa, estimated most soybeans in his area went in between May 15 and 30, after a smaller-than-average planting window from late April into early May. Rain and hail forced replant pockets, with some areas finishing planting in early June.

Midseason brought little insect, disease or weed pressure, though soybean gall midge appeared on the western side of his territory alongside septoria brown spot and cercospora leaf blight. SDS then arrived widely, with major outbreaks south of the Interstate 80 corridor — including fields where growers had never seen the disease before. Meyer expects 5% to 10% yield losses in some fields.

He could not offer a yield update: September may rank among the top 10 wettest on record in his area. "As soon as the weather breaks, combines will be rolling, and the crop will get harvested," he said.

Minnesota. Dale Viktora, Beck's field agronomist, reported a wet, cool pattern with some areas receiving 7 to 9 inches of rain in a 24-hour period. Most fields, regardless of relative maturity, have now evened out and will be ready simultaneously once weather allows.

Growers who harvested before the rain reported yields better than anticipated, though Viktora wants more results before drawing conclusions. He called the season a story of rainfall "haves" and "have nots" that will directly correlate to yields.

Timely planting, limited foliar disease and abundant sunny days, combined with ample rainfall in parts of the state, produced 75-to-80-bushel soybeans where conditions aligned.

With thistle burndown windows shrinking as nighttime temperatures fall, and saturated fields keeping combines parked from Iowa to Minnesota, the next stretch of dry weather will determine both the pace of harvest and the success of fall weed control heading into 2027.