Grazing trials on the Wallum of south-eastern Queensland. 2. Complex mixtures under common grazing

Abstract

Eight legumes and eight grasses in complex mixtures were grazed in common on a welldrained soil at Beerwah, south-east Queensland, for eight years. The aim was to study persistence and productivity and also to follow live weight changes in the cattle. Of the legumes, Trifolium repens, Desmodiam uncinatum, and Lotononis bainesii persisted and spread into other plots ; Centrosema pubescens, Medicago sativa, Phaseolus laithyroides, Trifolium incarnatum, and Desmodium sandwicense were not persistent. Among the grasses Paspalum notatum, P. dilatatum, Digitaria decumbens, and Chloris gaylana all persisted and spread ; P. plicatulum persisted but spread little, Panicum maximum var. trichoglme was reduced to trace proportions, while Paspalam conzmersonii and Brachiaria mutica finally disappeared. Legume content of the pastures was 25 to 30% and weed content about 20%. Annual and seasonal amounts of dry matter on offer are presented. Cattle gained weight for 38 weeks but made no gains for 14 weeks in winter. Once the pastures were well developed, the annual live weight gain was approximately 300 lb an acre. Nitrogen content of the pasture was satisfactory from spring to autumn.