In glasshouse experiments the increased nitrogen mineralization resulted in a large response of grass to lime. Light dressings of lime increased yield of clovers. This was not due to correcting manganese toxicity. Heavy dressings of lime depressed yield of clovers. This was not due to induced manganese deficiency but was, at least partly, due to induced phosphorus deficiency. Waterlogging the soil increased phosphorus availability and hence partly overcame the depressive effects of high lime. In field experiments ground limestone at 1 ton an acre was applied to a range of pastures and soil types on the coastal plain of south-western Australia. Pasture responses were poorly related to the original pH of the soil but were proportional to the increase in pH.