The purpose of this four year study was to evaluate the production consequences of using alum-treated poultry litter (ATPL) as a nutrient source for tall fescue and evaluate changes resulting changes in soil P status. Plots were established in the spring of 2000 at the Orange, VA on a Davidson loam (fine, kaolinitic, thermic Rhodic Kandiudult). Treatments included the application of ATPL, normal poultry litter (NPL) or triple superphosphate (TSP). These P sources were applied at rates based on the nitrogen requirement of the crop, P crop removal, or soil test P recommendations. During the four years of this study applications of ATPL resulted in P uptake similar to that found in treatments receiving NPL. No significant differences in Mehlich 1 soil P were found between the two litter sources. However, ammonium oxalate extractable P was significantly elevated in treatments receiving ATPL verses that found in treatments receiving NPL when means were pooled across application rates. A soil P fractionation procedure reveal significantly decreased H2O extractable inorganic P concentrations in soils receiving N-based rates of ATPL compared to equivalent applications of NPL. Also, the fraction of soil P extracted with 0.1 M NaOH, and then precipitated or otherwise made non-reactive with molybdate blue after acidification was significantly elevated in treatments which had received ATPL compared to those receiving NPL or TSP irregardless of P application rate. These results show that ATPL does not adversely affect fescue P uptake. Also, ATPL can have an impact of the form of P found in soils receiving long term applications. However these differences may not be detected through routine soil analysis.
See more of Phosphorus Chemistry in Soils: I. P Availability
See more of S11 Soils & Environmental Quality
See more of The ASA-CSSA-SSSA International Annual Meetings (November 6-10, 2005)