Abstract
SUMMARY Forage production of common vetch in semi-arid Mediterranean regions can be increased by varietal improvement. Dry matter content and crude protein yield were affected by environment more than crude protein content and harvesting date. Forage produced in environments where plants grew quicker was of lower dry matter content, higher crude protein content but of similar weight as forage produced in late environments. Variations in annual rainfall explained 35 to 76% of the total variation in dry matter yield.