Leaf and tiller growth of Lolium perenne and Agrostis spp. and leaf appearance rates of Trifolium repens in set-stocked and rotationally grazed hill pastures

摘要

Abstract Growth components of Lotium perenne and Agrostis spp. tillers and Trifolium repens stolon apices were compared for one year under set stocking and rotational grazing with sheep on hill pastures which had had low and high levels of fertiliser input. Leaf appearance rates of L. perenne and Agrostis spp. were unaffected by grazing management or fertiliser level. Leaf appearance in T. repens was also largely unaffected by treatments except in summer when rotational grazing allowed some relief from defoliation stresses and leaf appearance rates were greater than under set stocking during 3 grazing rotations. T. repens leaf appearance rates were slower in winter and increased later in spring than the grasses. For most of the year, tiller bud development in L. perenne was well below the maximum possible because of mutual shading in dense swards (mean total tiller density 29700 tillers/m2 under set stocking and 20 l00/m2 under rotational grazing). L. perenne lamina lengths, tiller lengths, and leaf exten...