Nitrogen fertilisation of weeping love grass (Eragrostis curvula) at Dohne

Abstract

Three field trials on the nitrogen fertilization of the Ermelo cultivar of Eragrostis curvula conducted over seven years were collated and reviewed. Dry matter yields in tons obtained from these trials, excluding first year results, were used to derive the regression equation y = 3.9x - 0.4 x squared + 1.3 for the yield response to increments of 100 lb of nitrogen per morgen per annum. This response was nearly linear up to 300 lb of nitrogen, and more than 400 lb of nitrogen was required for maximum dry matter production. The crude protein content of the herbage increased progressively with increasing rates of nitrogen. The recovery of fertiliser nitrogen varied from 51 to 70 per cent: the latter being achieved by the application of 300 lb of nitrogen. Ammonium sulphate produced considerably higher dry matter yields than urea or limestone ammonium nitrate when applied in a single dressing in the spring. When the nitrogen was applied in three dressings the yields from urea and LAN were increased and no longer significantly different from those due to ammonium sulphate.

Keywords: nitrate|fertilisers|ammonium|sulphate|urea|treatments|yields|limestones|herbage|crude proteins|nitrogen|fertilisation|grasses|Dohne Research Institute|cultivars|dry matter yields|regression equations