The Impacts of High Carbon Biochar on the Soil Quality and Grain Yield of a Three-Year Dryland Rotation.

Semi-arid climates in regions such as the Nebraska panhandle generally have low soil carbon content. Applications of soil amendments have been shown to improve soil quality. High carbon biochar produced by the Western Sugar Cooperative contains a carbon content as high as 30% as well as several micronutrients. It is hypothesized the application of the high carbon char may rapidly improve soil quality on degraded sites. In order to evaluate the impact of the application on crop yields and soil composition, a trial was initiated on two sites at the UNL High Plains Ag. Lab near Sidney, Nebraska in 2016 using a randomized complete block experimental design with four replications. Biochar was applied at rates of 0, 11, 22, 45, 67, and 90 Mg ha^-1on a three year rotation including corn, yellow field peas, and winter wheat with a turf top dresser on a highly eroded site as well as a higher quality site. The char was incorporated into the top 6 inches of the soil. Soil sampling was conducted prior to char application, and further sampling will proceed in the spring of each subsequent year before planting to monitor soil quality. Yield data has been collected for each crop at harvest. Wheat grain yield on the quality site was recorded as 4.45, 4.01, 3.65, 4.22, 4.26, 3.91 kg ha^-1 for the respective treatments, and the grain yield on the degraded site was 0.85, 1.71, 1.06, 1.43, 1.55, 1.75 kg ha^-1. No significant yield response has been recorded at this time. However, yield response is expected to increase in subsequent years of testing.