INCREASED YIELD

Ashburton Guardian, Volume 52, Issue 206, 13 June 1932, Page 7

INCREASED YIELD

. —„ / RESULT OF MANURING WHEAT. BTKGER profits obtained. According to the second annual report of the Wheat Research Institute very definite conclusions have been reached as the result of work carried out by the Department of Agriculture in connection with the manuring of wheat during the last seven years. "The experiments," says the report, "have been made with great exactitude by Mr A. W. .Hudson, and each experiment recorded is the average result of 12 to 20 plots, i As a result of 65 such composite experiments, up till the harvest of 1930, it was found that sowing superphosphate with the seed gave an average increase of yield of 4.5' bushels per acre, and the average profit from the use of super is about 16s 6d per acre. Super has been shown to be definitely superior to basic super, Ephos phosphate, and Nauru phosphate in Canterbury. "The harvest of 1931 saw 26 additional experiments harvested. In 20 cases out of the 26 increased yields were recorded, the average increase over the whole 26 trials being 3.2 bushels per acre. It took 1.3 bushels per acre to pay for the manure, and therefore at current prices the profit from using super was 8s Id per acre. This is lower than in any previous year, and it is thought that the very dry pre-harvest season caused the decrease in yield. Even with this lower yield, however, the advice still holds good' sow 1 cwt super with the seed. Further Experiments. "Up till 1930 the use of nitrate of soda had been paying on, the average. Fifty-seven trials showed an average increase (over that from super) of 4.T bushels per acre when nitrate of soda is top-dressed in the spring on wheat sown with superphosphate. Thus the profit from the combined use of super and nitrate of soda has been about £1 4s per acre. Sulphate of ammonia is recommended instead of nitrate of soda, as it is cheaper at the present time, and the net return per acre should go up by 3s or 4s. The harvest of 1931 saw 26 series of plots added to the previous 57. In the new series the result, again probably due to the dry pre-harvest weather, .was less favourable than in previous years, the increase in yield being only 2.6 bushels per acre, whereas 3.8 bushels are needed to pay for the manure; thus the average loss in 1931 from using nitrate of soda was 5s per acre. Last year, however, the advice was given to topdress in spring with sulphate of ammonia instead of nitrate of soda, on the ground that sulphate of ammonia, while cheaper, was probably equally effective. Eight series of plots were laid down to test this point, and apparently the conclusion on the equality of the two manures is at present justified Thus if sulphate of ammonia had been used instead of nitrate of soda on all the plots, and the increased yield had been the same, the loss from the nitrogenous manure would have been reduced from 5s to Is 6d per acre. Advice About Top-dressing. "Seeing that in previous years the increased yield from sulphate of ammonia was calculated at 27s per acre, and this year at a loss of Is 6d,per acre, there is no reason to alter the advice previously given: 'Top-dress with 1 cwt sulphate of ammonia in , August or early September if 1 cwt of super has been applied with the seed. Potash manuring again reduced yields. In all these trials the estimated profits are based on a price of 5s per bushel of milling-wheat. "Combining all the trials made by the Department into an average it is found that, the profits from sowing 1 cwt super with the seed and top-dress-ing with 1 cwt sulphate of ammonia ,w the spring resulted in a profit of 19s per acre over the cost of the manures. Thus, while the trials harvested in 1931 'are not as favourable as in preceding years, the following advice, published by the Department and endorsed by the 'institute last year, is almost certain to lead to financial gain to the wheat-grower: 'Sow 1 cwt super with the seed and top-dress with 1 cwt sulphate of ammonia in August or early September, or, if application is delayed, with 1 cwt nitrate of soda as late as the middle of October. For springsown wheat a mixture of super plus 1 cwt sulphate of ammonia should be sown with the seed.' "..