Fertilizer value of poultry litter applied by subsurface band vs. surface broadcast in corn production

Authors: Tewolde, Haile; Way, Thomas - Tom; BUEHRING, NORMIE - Mississippi State University; Jenkins, Johnie

Submitted to: Journal of Plant Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/24/2022
Publication Date: 9/4/2022
Citation: Tewolde, H., Way, T.R., Buehring, N., Jenkins, J.N. 2022. Fertilizer value of poultry litter applied by subsurface band vs. surface broadcast in corn production. Journal of Plant Nutrition. 46(9):2044-2059. https://doi.org/10.1080/01904167.2022.2118133.
DOI: https://doi.org/10.1080/01904167.2022.2118133

Interpretive Summary: Poultry litter has become a valuable row crop fertilizer in the past, but it is applied by an inefficient and largely wasteful surface broadcast method. In recent years, implements that apply manures in narrow bands below the soil surface on the side of the crop row have been developed by USDA-ARS engineers. While studies have shown that subsurface band applications reduce or eliminate the many drawbacks of the conventional surface broadcast method, whether the crop nutrient need can be met with less poultry litter application has not been tested. This study used economic analysis methods to determine if the poultry litter rate applied to corn for maximum profit can be reduced if applied by the relatively new method of subsurface banding, compared with the conventional surface broadcast method. The results showed that the poultry litter rate that maximized profit was 17% less if applied by subsurface banding than by surface broadcast, which shows the new subsurface band application is an efficient way of delivering the litter for corn production. This efficiency stems from the greater conservation of the nutrients, nitrogen in particular, derived from the litter if applied by subsurface banding than by surface broadcast. The results also showed corn grain enrichment with mineral elements including zinc and iron highly depends on the level of nitrogen fertilization and level of the nitrogen element in the grain. Overall, we expect these results to raise interest in the method and encourage the development and production of commercial implements for applying manures in subsurface bands.

Technical Abstract: The efficiency of applying poultry litter (PL) by subsurface banding (LSS) vs. the conventional surface broadcast (LBC) implies yield goals may be achieved with less PL. The objective of this study was to empirically determine if the profit maximizing PL rate (PLp) can be reduced if applied by LSS relative to LBC using economic analysis in corn production. Corn was grown with six PL rates ranging from 4.4 to 27.0 Mg ha-1 applied by LSS or LBC and with seven synthetic N (sN) rates ranging from 0 to 292 kg ha-1. Rates of PL or sN that maximized yield (PLy, sNy) or profit (PLp, sNp) were determined from yield curves and compared. The results showed PLy was greater than PLp by as much as 25% regardless of the application method. Both PLy and PLp were greater if applied by LBC than by LSS while the respective yields did not differ greatly. As much as 17% more grain was produced by 1 Mg ha-1 PLp if applied by LSS than by LBC. PL N availability was <37% if applied by LBC vs. >40% if applied by LSS. These results show that applying PL by LSS conserves N, leads to greater grain yield per 1 Mg PL, and thus the same corn yield may be obtained with less PL if applied by LSS than by LBC. The results also showed corn grain enrichment with mineral elements including Zn, Fe, Mn, P, K, and Mg highly depends on the level of N fertilization and grain N concentration.