Improving Winter Pasture Productivity

Summary

The trial at Keera compared the performance of livestock grazing on an unfertilised natural pasture with those grazing on a similar natural pasture which had been fertilised with 250 kg/ha single super (SS) in year one and 244 kg/ha SS in year two. The weight gains of livestock on the natural pasture (plus clover seed) were more than double those on the fertilised pasture when both mobs were given access to the same supplementary feed source in year two. Fertiliser application had no positive effect on weight gains during the winter months. The application of different rates of fertiliser at Thornleigh to what was originally intended is likely to have masked and certainly confounded any effect of the supplement. It is more likely that the greater weight gains achieved in paddock 1 were due to increased fertiliser application in combination with the provision of the urea supplement, but it is not possible to determine the relative influence of each. Animal performance at Cromarty was poor in both treatments, with animals losing weight from the date of entry into the paddocks. The rate of weight loss was reduced with the provision of the supplementary feeds. The addition of the fertiliser appears to have had little effect on pasture production or animal performance during the trial period. There was a low level of pasture available at the start of the trial and the quality of dry standing material was very poor. It is likely that feed availability in the paddocks was insufficient to meet the dry matter requirements of the stock, even with the introduction of the respective supplementary feed sources.