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Loss of soil nutrients in runoff accelerates eutrophication of surface waters. This study evaluated P and N in surface runoff in relation to rainfall intensity and hydrology for two soils along a single hillslope. Experiments were initiated on 1‐ by 2‐m plots at foot‐slope (6%) and mid‐slope (30%) positions within an alfalfa (Medicago sativa L.)–orchardgrass (Dactylis glomerata L.) field. Rain simulations (2.9 and 7.0 cm h⁻¹) were conducted under wet (spring) and dry (late‐summer) conditions. Elevated, antecedent soil moisture at the foot‐slope during the spring resulted in less rain required to generate runoff and greater runoff volumes, compared with runoff from the well‐drained mid‐slope in spring and at both landscape positions in late summer. Phosphorus in runoff was primarily in dissolved reactive form (DRP averaged 71% of total P), with DRP concentrations from the two soils corresponding with soil test P levels …