Fig. 1. Location of the nine simulated rainfall application sites within the study watershed. Refer to Table 1 for a description of site codes. Symbols indicate concentrations of soil test phosphorus using Morgan's extraction (1 M NaOAc, pH 4.8; Lathwell and Peech, 1965): open circle, 0 to 2 mg kg^–1; horizontal hatch, 2 to 5 mg kg^–1; vertical hatch, 5 to 10 mg kg^–1; cross hatch, 10 to 25 mg kg^–1; filled circle, >1000 mg kg^–1. The blacked out area indicates the boundary of the watershed above the monitoring station (open square).