By Strahinja Stepanović, Extension Educator, and Justin Richardson, Jovan Radojičić, Ognjen Zivkovic and Milica Bogdanovic, University of Belgrade-Serbia Agronomy Students

Continuous corn is the most common irrigated crop sequence in southwest Nebraska. Although rotating to other crops, such as soybeans, can mitigate some production issues of continuous corn and often boost the next year’s corn yield, larger adoption of soybeans has not readily occurred in this area. According to USDA Farm Service Agency planted acreage data, on average southwest Nebraska farmers plant irrigated soybeans every fifth year.

The culture of farming in southwest Nebraska revolves around corn, which often prevents growers from raising soybeans under more ideal conditions. For example, priority is often given to planting corn first, soybeans fields are often strip-tilled, planted in 30-inch rows, and seeding rates of >160,000 seeds/ac are very common. In addition, late season chemigation with nitrogen (N) is a widespread practice without the full understanding of when and where it’s warranted (Stepanovic et al., 2018a).

The objective of this study was to investigate the impact of planting date, row spacing, seeding rates, and N management on yield and yield components of irrigated soybean in southwest Nebraska.