Information on phosphorus (P) transport in agricultural landscapes has been mainly generated through plot-scale simulated rainfall experiments. These systems, though possessing several inherent advantages compared to natural rainfall-runoff collection, have significant gaps such as slope lengths not long enough to account for different hillslope erosion processes, water with ionic strength different from that of rain water, no variation of rainfall intensity/duration, and a lack of consideration of within season effects of crop growth and field equipment operations. In this study, a systems approach is being used on three hydrologically isolated hillslope tracts (3.7 x 36.6 m) and natural runoff is being collected using bulk overland flow samplers. All the fields have been planted in corn (with conservation tillage – fall chisel plow) but have extremes in residue cover created by different harvesting schemes, namely, grain (high residue), silage (low), and silage with fall manure application (intermediate). Runoff samples are being analyzed for total solids, volatile solids, particle size distribution (5 discrete size classes by gravity sedimentation - < 2, 2-10, 10-50, 50-500, and > 500 µm; continuous size distribution using laser diffraction), different forms of P (dissolved vs. particulate-bound), and P mass distribution in different size classes. In addition, unique information on the stability of aggregates transported by rill flow under these contrasting agricultural management systems will be presented. Relevant comparisons of particle size distributions and P mass in different size classes will be performed against off-site sediment and P loss measurements collected within the same farm using plot-scale simulated rainfall experiments (dominated mainly by inter-rill flow).