Full supplementation by free-choice feeding of rolled or ground barley to cattle on irrigated pastures brought them to acceptable slaughter condition within a 120 to 150 day feeding period in recent trials at Davis. Other factors also considered essential to the program included plenty of water nearby; a stocking rate of 5 to 7 head per acre or at least double the normal rate without supplement feeding; rotation of pastures to keep forage palatable and to facilitate irrigation; implanting each animal with 30 mg of diethylstilbesterol; and careful control of internal parasites.