The responses of tall fescue and white clover to lime and phosphorus on highly leached soils of the Natal Mistbelt

Abstract

The influence of lime and phosphorus on the performances of pure white clover and white clover/tall fescue swards on two highly leached Mistbelt soils was examined in factorial design. First season data, discussed in this paper, indicated highly significant dry matter responses to both lime and phosphorus. The pattern of response to phosphorus varied over the three harvests obtained in the season and a single optimum phosphorus level was not manifested for either clover or fescue. Decreases in extractable (0.05 N hydrogen sulphate) phosphorus levels with increasing lime rates were noted on both soils. Clover yield responses to lime were coincident with the reduction of soil acid saturations to below 18 percent. Fescue yield increased linearly with liming rate to the highest lime level applied (20,4 tonnes/ha); this response is thought to be partly attributable to the influence of lime on nitrogen mineralisation from soil organic matter.

Keywords: leached soils|Natal Mistbelt|seasonalities|dry matter responses|responses|soils|chemicals|acid|mineralisations|soil organic matter|weathered soils|KwaZulu Natal Province|tall fescue|white clover|lime|phosphorus