Repeated Poultry Litter Application Builds Cotton Soil Productivity

Annual broiler chicken litter application for 3 consecutive years affected cotton lint yield in the subsequent 3 years in direct proportion to the rate of application up to 6.7 Mg/ha litter. For example, residual litter increased lint yield in the 4^th year by about 69 kg/ha at one location and by 84 kg/ha at another location for every 1 Mg/ha/year litter applied every year in the previous 3 years. The residual yield advantage of 6.7 Mg/ha litter applied yearly in the first 3 years, therefore, was  207 kg/ha lint (69 x 3) at the first location and 252 kg/ha lint (84x3) at the other location in the fourth year.  The results suggest the rate of chicken litter applied yearly to the same soil for optimum cotton production may be reduced progressively with subsequent application beyond the fourth year.