Author
Tewolde, Haile | |
Way, Thomas - Tom | |
Pote, Daniel | |
Adeli, Ardeshir | |
Brooks, John | |
SHANKLE, M - Mississippi State University |
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 1/9/2013 Publication Date: 4/1/2013 Citation: Tewolde, H., Way, T.R., Pote, D.H., Adeli, A., Brooks, J.P., Shankle, M.W. 2013. Method of soil sampling following subsurface banding of solid manures. Agronomy Journal. 105:519-526. Interpretive Summary: Soil sampling guidelines do not exist for fields fertilized with solid manures applied in bands. The objective of this work was to describe the distribution of mineral nutrients and total C and propose a new method of taking soil samples that reflect the fertility level of a field following manure application in narrow bands below the soil surface. Systematic soil core samples were taken from no-till cotton (Gossypium hirsutum L.) plots fertilized with poultry litter in subsurface bands spaced ˜1 m apart and analyzed for total C, total N, and extractable P, K, Mg, Cu, Mn, Fe, and Zn. The results show that total C and most of the mineral nutrients are not evenly or randomly distributed in the space between and across the bands because of the manure placement in narrow bands, nutrient movement away from the band, and plant uptake. The concentration of the elements P, K, Mg, Zn, Cu, and B in soil samples taken over the band was elevated by up to 50 fold compared to positions away from the band. This distribution shows that random soil sampling from fields fertilized with manures in bands is not appropriate and that some systematic sampling schemes must be utilized. We describe a new sampling method that takes into account the band width and the spacing between consecutive bands. The method is based on a proportional mixing of soil cores taken at predetermined distances from the manure band including one core directly over the band. Technical Abstract: Soil sampling guidelines do not exist for fields fertilized with solid manures applied in bands. The objective of this work was to describe the distribution of mineral nutrients and total C and propose a method of taking soil samples that reflects the fertility level of a field following manure application in narrow bands below the soil surface. Systematic soil core samples were taken from no-till cotton (Gossypium hirsutum L.) plots fertilized with poultry litter in subsurface bands spaced ˜1 m apart and analyzed for total C, total N, and extractable P, K, Mg, Cu, Mn, Fe, and Zn. The results show that total C and most of the mineral nutrients are not evenly or randomly distributed in the space between and across the bands because of the manure placement in narrow bands, nutrient movement away from the band, and plant uptake. Concentrations of the elements P, K, Mg, Zn, Cu, and B in soil samples taken over the band were elevated by up to 50 fold compared to positions away from the band. This distribution shows that random soil sampling from fields fertilized with manures in bands is not appropriate and that some systematic sampling schemes must be utilized to more accurately represent the soil nutrient status. We describe a new sampling method that takes into account the band width and the spacing between consecutive bands. The method is based on a proportional mixing of soil cores taken at predetermined distances from the manure band including one core directly over the band. |