Armstrong Research and Demonstration Farm
Most past research has shown a yield benefit to planting soybeans in rows more narrow than 30-in. However, narrow rows occasionally can result in more soybean disease problems, such as white mold, which can result in higher yields with wider rows. Yield differences between wide and narrow rows often vary from year-to-year and fieldto-field.
Iowa State University
Fawcett, Jim; Sievers, Josh; Rossiter, Lyle; and Rogers, Jim, "On-Farm Soybean Row Spacing Trials" (2015). Iowa State Research Farm Progress Reports. 2140.