Dryland grain sorghum yields in the southern Great Plains increased significantly from 1939 to 1997, with a 139% increase in yields from 1956 to 1997. Improved hybrids contributed to 46% of the yield increase, while changes in soil water at planting due to better management practices accounted for the remaining 93%. Annual grain yields increased by about 50 kg ha −1 during this period, showing the impact of improved farming techniques on crop productivity.