The Distribution of White Clover (Trifolium repens L.) and Grasses within Six Sown Hill Swards

potassium. (3) White clover was adversely affected by soil acidity and appeared more sensitive to soil aluminium than the grasses. (4) White clover was usually positively associated with Lolium perenne and negatively with Agrostis tennis Sibth. Lolium perenne was usually positively associated with Poa spp. and negatively with Agrostis tennis. (5) White clover appeared to be reduced by shortage of moisture on relatively shallow soils. (6) Molehills which remained raised were largely colonized by species other than white clover and Lolium perenne. (7) Farmers wishing to encourage white clover should therefore apply sufficient lime, grow the clover with Lolium perenne rather than with Agrostis tennis, choose sufficiently deep soils, and control moles.