Purpose Phosphorus (P) is a limiting nutrient for most US Midwestern aquatic systems and, therefore, increases of P, through point or non-point sources (NPS) of pollution such as agriculture,causeseutrophication. Identifying specific NPS contributions (e.g., upland vs. stream channels) for sediments and P is difficult due to the distributed nature of the pollution. Therefore, studies which link the spatial and temporal aspects of sediment and P transport in these systems can help better characterize the extent of NPS pollution. Materials and methods Our study used fingerprinting techniques to determine sources of sediments in an agricultural watershed (the North Fork of the Pheasant Branch watershed; 12.4 km 2 area) in Wisconsin, USA, during the spring, summer, and fallseasons of2009. Theprimary sources considered were uplands (cultivated fields), stream bank, and streambed. The model used fallout radionuclides, 137 Cs, and 210 Pbxs, along with total P to determine primary sediment sources. A shorter-lived fallout radioisotope, 7 Be, was used to determine the sediment age and percent new sediments in streambed and suspended sediment samples (via the 7 Be/ 210 Pbxs ratio). Results and discussion Upland areas were the primary source of suspended sediments in the stream channels followed by stream banks. The sediment age and percent new sediment for the streambed and suspended sediments showed that the channel contained and transported newer (or more recently tagged with 7 Be) sediments in the spring season (9–131 days sediment age), while relatively old sediments (165–318 days) were moving through the channel system during the fall season. Conclusions Upland areas are the major contributors to instream suspended sediments in this watershed. Sediment resuspension in stream channels could play an important role during the later part of the year. Best management practices should be targeted in the upland areas to reduce the export of sedimentsandsediment-boundPfromagriculturalwatersheds.