The influence of weather on the quality of tropical legume pasture during the dry season in Northern Australia. I. Trends in sward structure and moulding of standing hay at three locations

Abstract

In seasonally dry tropical climates, animal production is severely constrained during the dry season by the low nutritive value of dry grass forage. Introduction of a legume such as Caribbean stylo can provide a valuable alternative forage during this period, mainly in the form of leaf litter and accompanying seed. The actual contribution of dry legume is closely dependent on its moisture regimen, which determines the degree of mould growth, an important palatability factor. This paper reports a 2-year study conducted at Katherine, Darwin and Townsville of the environmental control of both the timing and rate of leaf shed and of the subsequent moulding of leaf litter. At Katherine and Darwin, leaf was shed early and rapidly; at Townsville, much lower evaporation rates and small rainfalls delayed and prolonged leaf shed by several weeks. The data provide a model for predicting leaf shed by using standard weather data to aid the assessment of the risk of forage damage by precipitation.