Title: AVAILABILITY OF POULTRY LITTER COMPOST P TO FESCUE
Submitted to: Proceedings Annual Conference US Composting Council
Publication Type: Proceedings
Publication Acceptance Date: December 25, 2002
Publication Date: December 29, 2002
Interpretive Summary: Guidelines to control the available P added to soils are being discussed in many states. Phosphorus has been associated with algal blooms in surface waters. Nitrogen had been the concern for several years because there is a drinking water standard for nitrate. Now research is focusing on P content of amendments to soils, especially manures and composts in regions where animal production is concentrated. A study was conducted to compare poultry litter compost to triple super phosphate, a common commercial fertilizer. The data showed that poultry litter compost was equal to triple super phosphate. Farmers can substitute poultry litter compost for triple super phosphate simply by having a total P analysis conducted on the compost and applying according to the phosphorus needs of the crop. Farmers can comply with nutrient management plans using a one-for-one poultry litter compost for triple super phosphate substitution.
Application of manures and composts to soils should follow recommended nutrient management plans so that nutrients in excess of plant needs are avoided. Recently, levels of P in agricultural soils have been investigated closely because inputs of P are out of line with outputs. Accumulation of P in soils has been steadily increasing. The P fertilizer value of poultry litter compost (PLC) has not been thoroughly investigated. Studies were conducted to compare triple super phosphate to PLC in a pot study using fescue and Sassafras soil. Phosphorus availability of PLC was equal to TSP. Data suggested that PLC-P may be more available than TSP-P when N becoming limiting, but addition of N after the second harvest did indicate that PLC-P was not greater than but equal to TSP. Numerous factors associated with soil chemistry of compost P availability including biological activity, metal content and pH may have influenced the results.