Are you worried about your soybean stands? “If you have 80,000 plants per acre, keep what you have,” says Steve Gauck, a regional agronomist for Beck’s, based near Greensburg, Ind. “Often, even 70,000 is enough if weeds are controlled.”

For this year’s Soybean Watch project, Gauck will observe a soybean field in south-central Indiana. Hopefully, lessons learned will apply to scenarios in your soybean fields. Beck’s sponsors Soybean Watch ’24.

“The first step is getting an accurate stand count,” Gauck says. “The hula hoop method works. Roll the hoop at random several times at each location, and at multiple locations within the field. Arrive at an average.”

Find handy information about the hula hoop approach and linear row length methods at this Iowa State University resource. You can also find a table for turning hula hoop plant counts into estimated plant populations in the Purdue University Corn and Soybean Field Guide.

The table below, compiled using information from Iowa State and Purdue, simplifies calculations. For example, if the interior diameter of the hoop is 30 inches and you average 10 plants per toss, final plant population is around 89,000 plants per acre. “That’s on the thin side, but data indicates it’s sufficient,” Gauck says.

Decision time

“One of the most challenging decisions farmers face is whether to replant,” says Chad Kalaher, Beck’s field agronomist for eastern Illinois. “Factors to consider when thinking about replanting or thickening a stand include original planting date, soil type, expected weed pressure, current soybean population, current soybean growth stage and current date.”

Based on Beck’s Practical Farm Research from multiple-year, multiple-location experiments, leaving timely planted soybean stands of 70,000 plants per acre or greater is the best agronomic and economic decision, Kalaher notes. For sandy soils or fields with high weed pressure, the population replant threshold may be slightly higher.

“Consider assessing stands and making decisions no later than the V1 or first trifoliate growth stage,” he adds.

From the field

Here are observations from Beck’s agronomists across the Corn Belt:

Illinois. “Many farmers with well-drained soils got a decent start planting soybeans in April. Some in more southern counties completed soybean planting prior to rains on April 23. Seeding depth and soil temperature were very good for rapid germination of April 8 through April 20 planting dates.” — Chad Kalaher, east-central and northeast Illinois

Missouri. By April 23, many beans were emerging in southern counties. In other areas with tougher soils, some growers were concerned about how well beans would push through crusting after rains. Some held off planting in late April to see how rains turned out. – Celena Kipping, southwest Missouri

Nebraska. About 5% to 10% of soybeans were planted in early April, primarily in Richardson, Pawnee, Nemaha and Otoe counties in southeastern Nebraska. Soybeans were emerging. Soil conditions were favorable during the early stretch. Rain and storms developed in some areas afterward. – Trey Stephens, eastern Nebraska