A study of the potential of lucerne as a silage crop in a high-rainfall area

The results are reported of a 2-year plot experiment investigating the potential of lucerne as a silage crop in a comparatively high-rainfall area (annual average of about 900 mm). The performance of the lucerne on the remainder of the field in which the plot experiment was located is also discussed. With below-average rainfall in the sowing year a good establishment was obtained and a single cut to a stubble height of 75 mm in August gave a dry matter yield of 3 t ha^-1. In the first harvest year, summer rainfall was again below average and a total dry matter yield of 13·8 t ha^-1 resulted from three cuts to 75 mm above ground level. However, the total yield was reduced to 10·11 ha^-1 in the second year when the rainfall was considerably above average. Attempts to increase the feeding value of the lucerne herbage by increasing cutting frequency and by increasing cutting height showed little effect over the standard system of three cuts to a stubble height of 75 mm. The effects of applying potassium fertilizer at rates supplying 100,200 or 300 kg K ha^-1 either as a single spring dressing or in equally divided dressings were not significant in either of the two years