USE OF NITROGEN

Timaru Herald, Volume CXXXIV, Issue 18832, 21 March 1931, Page 10 (Supplement)

USE OF NITROGEN

PROLONGING THE SEASON. The fact that for the past three seasons grazing experiments had been carried out throughout New Zealand, mainly to determine the economic aspect of the use of nitrogenous manures as a means of increasing carrying capacity as measured by butter-fat production, was referred to by Dr. H. E. Annett, chief advisory officer in New Zealand to Imperial Chemical Industries, Limited, in his address to the Institute of Chemistry at Nelson recently. In Europe, he said, it had been shown that the use of nitrogenous manures enabled grass to be produced much earlier in the spring. Continuing, he remarked that in 1929 over 500 tons of sulphate of ammonia was used in New Zealand, and during 1930 nearly 9000 tons had been used. Most of this had been used on grassland. Undoubtedly it had, in most cases, enabled farmers to product more feed early in the spring, and thus it had been possible for them to bring their cows in earlier. “The Department of Agriculture’s experiments were designed to try and get some measure of the value of nitrogen,” said Dr. Annett. “However, the problem is not a simple one. In the case of the wheat experiments we had a straight-out problem. In order to measure the value of nitrogen for pasture ideally we should have whole farms Iv or >.ted with and without nitrogen. Apart, however from the expense of such experiments one would have differences due to management, and so on. It was decided, therefore, to take a field on numerous farms and to divide it into two. The whole was to be treated with superphosphate and one half was to receive periodical dressings of nitrogen throughout the year. The farmer had to graze the paddocks with his cows as they were ready, and had to keep a record of the number of grazing days obtained on each plot. From this, at the end of the season the amount of butter-fat produced on each field was calculated. “There are obvious drawbacks to such experiments. For example, feed produced early in the spring by nitrogen was valued at the same figure as feed produced a little later. Obviously, the earlier feed is much more valuable, as it enables the farmer to bring his cows in earlier, and so increase the length of his season.”