The distribution of white clover (Trifolium repens L.) and grasses within six sown hill swards.
The distribution of T. repens and grasses was examined in 6 hill swards in mid-Wales sown 10-39 years before with seed mixtures containing T. repens and Lolium perenne. T. repens distribution was generally not related to soil P or K. T. repens was adversely affected by soil acidity and appeared more sensitive to soil Al content than the grasses. T. repens was usually positively associated with L. perenne and negatively with Agrostis tenuis [A. capillaris]. L. perenne was usually positively associated with Poa spp. and negatively with A. tenuis. T. repens appeared to be reduced by shortage of moisture on relatively shallow soils. Molehills which remained raised were largely colonized by species other than T. repens and L. perenne. It was concluded that farmers wishing to encourage T. repens should therefore apply sufficient lime, grow it with L. perenne rather than with A. tenuis, choose sufficiently deep soils and control moles.