Liming effects of beef cattle feedlot manure or compost

Soil pH can be increased by manure or compost application because feed rati ons usually contain calcium carbonate. This study was conducted from 1992 t o 1996 to evaluate effects of phosphorus (P) and nitrogen (N)-based manure and compost application management strategies on soil pH level. Composted a nd uncomposted beef cattle (Bos taurus) feedlot manure was applied to suppl y N or P needs of corn (Zea mays L.) for either a one- or two-year period. Phosphorus-based manure or compost treatments also received additional fert ilizer N (ammonium nitrate) to provide fora total of 151-kg available N ha( -1) yr(-1). Fertilized and unfertilized checks also were included. Manure a nd composted manure contained about 9 g CaCO3 kg(-1) resulting in applicati on rates of up to 1730 kg CaCO3 ha(-1) in 4 years. The surface soil (0-150 mm) pH was significantly decreased with ammonium nitrate application compar ed to soil in the unfertilized check or to soil receiving manure or compost . Soil pH was significantly increased with the N-based management strategy compared with the soil original level. In contrast, 4 yr of P-based manure and compost application strategy maintained soil pH at the original level. Nitrogen-based applications resulted in higher soil pH than P-based. Beef c attle feedlot manure and compost can be good sources of CaCO3 for soils req uiring lime addition.