Fig. 6. Mean total phosphorus (TP) load in runoff as affected by time of rainfall simulation (one [1MO] and six months [6MO] after P amendment application); P source (control, TSP = 54 kg P ha^–1 as triple superphosphate, LM = low swine manure rate, and HM = high swine manure rate); and application method (surface-applied and incorporated, where the control and TSP were chisel-plowed, and LM and HM were injected). Mean values (n = 16) that have the same letters are not significantly different (P < 0.1) as determined by the Scheffé test.