Impact of Alum‐Treated Poultry Litter Applications on Fescue Production and Soil Phosphorus Fractions

Abstract

The purpose of this 4‐yr study was to evaluate tall fescue (Festuca arundinacea L.) production and changes in soil P fractions resulting from alum‐treated poultry litter (ATPL) applications. Plots were established in the spring of 2000 at Orange, VA, on a Davidson loam (fine, kaolinitic, thermic Rhodic Kandiudult). Treatments included the application of ATPL, non‐treated poultry litter (NPL) and triple superphosphate (TSP) at rates based on current litter management strategies in Virginia. During the 4 yr of this study, applications of ATPL resulted in forage yield and P uptake similar to that found in treatments receiving NPL. Also, no significant differences in Mehlich‐1 extractable soil P between litter treatments were observed after 4 yr of application. A soil P fractionation procedure revealed significantly decreased H2O extractable inorganic P (Pi) concentrations in soils receiving N‐based rates of ATPL compared with equivalent applications of NPL. Conversely, the organic P (Po) fraction extracted with 0.1 M NaOH was significantly elevated in treatments that had received ATPL compared with those receiving NPL or TSP regardless of P application rate. The results indicate that applications of ATPL does not adversely affect P uptake by fescue or forage production. This study also shows that ATPL can have an impact on the forms of P found in soils following continued applications; however, these differences may not always be detected through routine soil analyses such as the Mehlich‐1 extraction.