Enhancing Management of Fall‐Applied Poultry Litter with Cover Crop and Subsurface Band Placement in No‐Till Cotton

Abstract

Whether the yield reduction risk in cotton (Gossypium hirsutum L.) fertilized with fall‐applied poultry litter, relative to spring‐applied litter, in regions with warm falls or winters can be minimized by applying the litter in subsurface bands along with a winter cover crop is unknown. A field study was conducted in Mississippi to determine whether litter applied in fall can be as effective as litter applied in spring for no‐till cotton if applied in narrow subsurface bands (SSB) in the presence of a winter wheat (Triticum aestivum L.) cover crop (WCC). The study compared 5.6 Mg ha−1 litter applied in the fall vs. spring, in SSB vs. surface broadcast (BC), with a WCC vs. no cover crop (NCC) in a 2 × 2 × 2 treatment structure. An unfertilized control and a treatment fertilized with conventional inorganic fertilizers were included. The results showed that planting wheat as a WCC, relative to NCC, increased cotton lint yield by as much as 18% in the driest season. Applying litter in fall leads to loss of litter‐derived nutrients if applied by BC, but the losses are reduced if it is applied as SSB. Applying litter as SSB in conjunction with a WCC increased cotton lint yield relative to BC application with NCC by as much as 22%. The combined benefit of cover crop and subsurface banding suggests that poultry litter may be applied in fall in these soils without yield penalty, with potential to reduce the litter rate and minimize environmental contamination.