Influence of weather and nitrogen fertilization on white clover percentage of permanent grassland.

On humus sandy soil little affected by moisture deficiency, and on compact river clay with somewhat lower water-table (40-180 cm) and occurrence of water deficiency during the summer months, herbage sampling during 1960-1966 showed that the percentage of Trifolium repens present in any month was significantly correlated with temperature and total radiation for the previous month. The mean clover percentage for a single season correlated significantly with mean April temperature. At temperatures common in April, growth of clover is considerably more affected by a rise in temperature than is that of the competing grasses Loliuni perenne and Poa trivialis. The clover percentage was unfavourably affected by N application but unaffected by precipitation or potential evaporation. (Abstract retrieved from CAB Abstracts by CABI’s permission)