Increases in the growth of forage and in pounds of lamb produced per acre were achieved by the use of fertilizers and introduced range plants in a study made at the Hopland Field Station during the winter and spring of 1956. In the low feed production period—January and February—the improved pastures yielded about three and one half times as much forage as untreated native range. Ewes with lambs were maintained in better condition and lambs gained slightly faster during the early winter months on the improved range compared to native pastures. However, by the end of May, the average lamb weight was the same in both groups. Also, the pasture treatment resulted in an increase of 141 sheep days per acre for the five-month period ending May 28.