Placement of Poultry Litter Bands in No-till Cotton Production.

Implements for applying manures in narrow bands parallel to plant rows have been developed in recent years. Proper manure band placement relative to the plant row for efficient accessibility and conservation of nutrients has not been investigated. The objective of this study was to determine whether horizontal and vertical placement of poultry litter bands affects conservation and availability of manure-derived nutrients in a no-till cotton production system. The study compared 6.2 Mg/ha fresh broiler chicken litter applied in subsurface bands spaced 1.01 m apart versus the same litter rate applied in subsurface or surface bands spaced 0.30 m apart.  An unfertilized control and a standard treatment fertilized with synthetic fertilizers were also included.  No-till cotton was planted parallel to the litter bands. The results showed that concentrating the litter in single subsurface bands per row of cotton (wider spacing) conserves more litter-derived N than when the litter is split into multiple subsurface bands (narrower spacing).  Less N is conserved if the litter is applied by surface banding relative to subsurface banding regardless of the band spacing. Extractable soil mineral elements and pH increased across years in all treatments. Applying litter by any of the three methods increased soil pH relative to applying inorganic fertilizers. Young cotton plants appeared to access litter nutrients better if the bands were closely spaced.  Litter elevated concentrations of selected mineral elements in the soil. The results demonstrate that spacing of manure bands affects nutrient conservation and availability in no-till cotton production systems and that continuous cotton modifies chemical properties of a newly cultivated upland soil.