A comparison of Vicia species for summer grazing and subsequent oat crop production in Western Australia

Abstract

Vicia species were grown alone, or with oats, in a continuous cropping system for summer grazing. Ten cultivars were selected from the species V. atropurpurea, V. dasycarpa, V. sativa and V. articulata. There was a maturity range of five weeks. They were sown in 1968 and allowed to regenerate for three more years. Production of dry matter and grain yield were recorded for the first three years. The liveweight trends of sheep grazing the dry herbage were measured for the first two summers. In the final two years the competitive ability of the vetches when oversown with oats, and the yields of the oat crops were measured. V. atropurpurea generally yielded most dry matter and V. articulata the least. V, sativa gave the highest seed yields. In 1968, 18-month-old sheep lost weight on all cultivars. In 1969, six-month-old sheep gained weight and these liveweight gains were positively correlated with the yield of vetch dry matter. The yield of oats was significantly correlated in both 1970 and 1971 with the 1969 vetch yield. Most of the vetches regenerated well, both on their own and when oversown with oats. The later maturing V. atropurpurea and V. dasycarpa persisted better than V, sativa and V. articulata cultivars. V. dasycarpa cultivars contained significantly higher concentrations of nitrogen than those of other species. The nitrogen concentration was higher in vetches grown alone than when grown with oats. The results suggest that V. dasycarpa and V. atropurpurea are the most suitable species in a continuous cropping system for summer grazing.