Strategies to Reduce Inorganic Fertilizer Inputs in Crop Production through Integrated Crop-livestock Systems

Adequate nutrition is essential for crop growth, production, and profit potential for farmers, but chemical fertilizer costs alone can constitute a greater portion of the total variable costs for wheat and canola. The present study evaluated seven cropping treatments (CT) in a 3-year crop rotation under two different soil types. Five of the CTs consisted of a one-time application (year 1) of beef cattle manure, and growing of cover crop cocktails (CCC) for annual pasture, swath grazing, green manure, and green feed. Canola and wheat were respectively grown in years 2 and 3 of the 3-year crop rotation. In year 2, CTs impacted canola seed yield and seed protein (only at site 2). Wheat had similar protein content in year 3 at both sites. At both sites, the application of beef cattle manure in year 1 seemed to encourage higher plant tissue P at the expense of plant tissue Zn. Overall, beef cattle manure and CCCs based CTs improved soil N, P, and K, but beef cattle manure application consistently improved crop yield and significantly reduced the need for additional in-organic fertilizer application to canola and wheat in subsequent years.