Fig. 1. Long-term (25 d) phosphorus release from poultry litter (PL)–treated and untreated Coastal Plain soils (pH 6) after 1 wk of incubation as determined by the batch desorption technique using 2 mM 2-(4-morpholino)-ethane sulfonic acid (MES) buffer and 0.098 M NaCl (pH 6) desorptive solution with a 1:30 solid to solution ratio. Soil + lit, soil incubated with control litter; soil + al-lit, soil incubated with alum-amended litter. Significant differences between the mean cumulative P release are denoted by different letters at the end of the desorption curve. (A) Evesboro loamy sand, (B) Rumford loamy sand, and (C) Pocomoke sandy loam.