Opening Up the Manure Application Window in a Sustainable Approach

The application of liquid swine finishing manure to farm fields represents a significant expense for livestock producers despite the nitrogen, phosphorus and potash contained in the manure. In the Western Lake Erie Basin of Ohio, an area more than 3 million acres in size, surveys have shown approximate half the livestock manure generated annually is applied in the fall after crops are harvested. (Zhang et al., 2015) This allows much of the manure nitrogen to be lost to leaching before the following crop season. The ammonium nitrogen in fall applied swine finishing manure can be captured by growing crops. A fall cover crop study (Sundermeier 2010) indicated a growing radish crop reduced soil nitrate nitrogen levels from 21.3 ppm to 6.5 ppm. This prevented the nitrogen from being lost from the field, but the only a portion of the organic matter created would mineralize the following crop season to provide nitrogen for a growing crop. The incorporation of swine finishing manure directly into a growing corn crop with a manure tanker has proven to provide corn yields similar to commercial fertilizer (Arnold et al., 2017). Soil compaction was a concern with the heavy manure tanker. Using a drag hose to incorporate the manure into emerged corn should overcome the soil compaction concern and allow the corn crop to utilize the available nitrogen in the swine finishing manure. The money saved by not needing to purchase commercial nitrogen to sidedress the corn crop could more than pay for the manure application. This study was designed to determine if the ammonium nitrogen in liquid swine finishing manure could produce corn yields similar to commercial 28 percent urea ammonium nitrate (UAN) when the manure was applied to emerged corn using a soft drag hose. In each of the four years of this randomized complete block design study (2014-2017) manure was incorporated at a rate of 6,500 gallons per acre to provide approximately 210 pounds per acre of nitrogen. The 28% UAN treatment was applied at approximately 70 gallons per acre to provide 210 pounds of nitrogen per acre. All treatments also received 10 gallons of 28% UAN as a row starter fertilizer at planting time to provide approximately 30 pounds of nitrogen. Over the four years of this study, the incorporated swine finishing manure treatments out-yielded the incorporated 28% UAN treatments by an average of 14.8 bushels per acre. This varied from no yield increase the 1st year (2014) to a 33 bushel-per-acre yield increase in the unusually wet growing season of 2015.AUTHOR AFFILIATION: Samuel Custer, OSU Extension educator, agriculture and natural resources, Darke County, custer.2@osu.edu (Corresponding Author); Glen Arnold, OSU Extension field specialist, nutrient managementThe application of liquid swine finishing manure to farm fields represents a significant expense for livestock producers despite the nitrogen, phosphorus and potash contained in the manure. In the Western Lake Erie Basin of Ohio, an area more than three million acres in size, surveys have shown that approximately half of the livestock manure generated annually is applied in the fall after crops are harvested. (Zhang et al., 2015) This allows much of the manure nitrogen to be lost to leaching before the following crop season. The incorporation of swine finishing manure directly into a growing corn crop with a manure tanker has proven to provide corn yields similar to commercial fertilizer (Arnold et al., 2017). Soil compaction was a concern with the heavy manure tanker. Using a drag hose to incorporate the manure into emerged corn should overcome the soil compaction concern and allow the corn crop to utilize the available nitrogen in the swine finishing manure