tIn the Senegal River Valley (SRV), there was substantial yield gap between potential and actual yieldobtained by farmers in irrigated rice production systems. Integrated crop management (ICM), coveringalmost all the agricultural practices from land preparation to harvest, was introduced to farmers forboosting yields since the early 2000s. A repeated farm survey was conducted over the period 2002–2010to monitor farmers’ agricultural practices during the wet season in the Delta and Middle Valley of theSRV. The objectives of this study were to: (i) assess spatial and temporal variation in on-farm yields,and (ii) determine factors affecting variation in the yields through Classification and Regression Tree(CART) analysis. The data set consists of 829 farmer-year observations. While mean yields across nineyears were 5.0 and 5.6 t/ha in the Delta and Middle Valley, respectively, mean attainable yields (upper10 percentile) were 7.2 and 8.6 t/ha, respectively. Yield gap between attainable yield and mean yield was2.2–3 t/ha. There were no temporal trends in yield or yield gap in either zone. CART analysis identified sixand eight yield determining factors. The primary factor was sowing time, and delayed sowing resulted inyield reduction by around 1 t/ha in both zones. The major reasons behind delayed sowing were relatedto availability of credit, machinery, and irrigation water. The two other commonly identified factorswere fertilizer management and bird control. We conclude that creating enabling environment throughinstitutional arrangements for improving access to resources and machineries is essential for enhancingthe adoption of ICM and breaking the yield stagnation. Development of alternative agricultural practicessuch as no tillage system is also needed to help farmers practice timely sowing.