Establishment of ryegrass, cocksfoot, and white clover by oversowing in hill country

摘要

Abstract ‘Grasslands Nui’ perennial ryegrass (Lolium perenne L.), ‘Grasslands Wana’ cocksfoot (Dactylis glomerata L.), and ‘Grasslands Huia’ white clover (Trifolium repens L.) were surface-sown in spring into pre-treated hill country swards. Appearance, survival, and morphological development of seedlings were measured. Final seedling appearance of the grasses was similar (33% of seed sown) although ryegrass seedling appearance was more rapid than cocksfoot for the first 24 days after sowing. White clover seedling appearance was 58%. Survival of seedlings in plots laxly grazed before sowing was generally poorer than in hard-grazed or herbicide-treated plots. Species differed in seedling survival in the order: ryegrass= cocksfoot = white clover. Mean establishment levels 145 days after sowing were 30% for white clover, 23% for cocksfoot, and 25% for ryegrass. Herbicide treatment substantially improved seedling development for all 3 species. Analysis of the fate of grass seed showed losses were greatest imm...