Compost Carryover Effects on Utah Dryland Organic Wheat.

Dryland wheat is the primary crop grown in much of the arid and semi-arid western U.S. Yields are constrained by lack of rainfall, so the wheat-fallow system is typically employed. In such a system, no crop is grown in the fallow year, thus enabling an additional year of water to accumulate in the soil to produce a single crop. Organic dryland wheat-fallow systems risk major soil loss due to dependency on tillage for weed control and a lack of economically viable organic inputs to improve yield and return residue to the soil.  The objective of this study was to characterize the effect of compost carryover on dryland wheat yield and quality. Research trials were initiated at the USU Dryland Research Station at Blue Creek in 2011. Treatments consisted of compost applied at 0, 12.5, 25, and 50 Mg/ha, and no compost + conventional fertilizer. Treatments were arranged in a randomized complete block design with four replications. Wheat growth, yield, and quality was determined in 2012 and 2014.