Previous legume crop influences winter barley yield, N fertilizer response, and malting quality in Missouri

The rapid growth in the craft brewing industry is increasing the demand for winter barley production. Little recent research exists on producing winter barley for malting in the lower Midwestern United States, with a lack of understanding how previous legumes crops grown in rotation with winter barley interact with nitrogen (N) fertilization rates to affect grain yield and malting quality. To investigate these topics, a preliminary, 1-year study was conducted in Missouri, USA, to test how growing soybean, a common rotational crop, and sunn hemp, a specialty forage crop, prior to winter barley, as well as two fall N fertilization rates (22.4 and 44.8 kg N ha⁻¹), affected barley grain yield. Barley grain yield was unaffected by the previous legume crop choice or the fall N fertilization rate, suggesting that either crop provided adequate residual N to the succeeding barley crop. Additionally, malting quality was analyzed from representative grain samples to reveal adequate levels suitable for use in the craft brewing industry. This study's results reveal preliminary data supporting winter barley production in the lower Midwestern United States, with an indication that previously grown legume crops impact crop yield greater than fall N fertilizer rate.