Shoot characteristics of Trifolium repens grown in association with Lolium perenne or Holcus lanatus in pastures grazed by sheep

The morphological characteristics of Trifolium repens, grown in association with either Lolium perenne or Holcus lanatus and grazed by sheep to maintain sward surface heights of 3 cm, 5 cm and 10 cm, were measured. The lamina area, petiole length, internode length and internode weight of T. repens were significantly greater when H. lanatus was the companion grass than when L. perenne was the companion grass. All of these characteristics, together with the number of laminae per stolon, were also greater in the taller swards than in the shorter swards. The number of branches on each shoot did not vary significantly with either companion species or sward height treatment. Except for the effects of the treatments on the number of branches, the results are generally consistent with the known effects of variation in foliar shading on the morphology of T. repens.