EXCESSIVE PRICES FOR PHOSPHATIC MANURE.

Otago Witness, Issue 3097, 23 July 1913, Page 14

EXCESSIVE PRICES FOR PHOSPHATIC MANURE.

Mr G. M. Thomsen threw a regular bombshell on the floor of the House of Representatives in regard to phosphatic manures when he stated that “the unit cost of 50 per cent, phosphate rock on the cars in Florida would be as against the 2s the farmers were paying now. Similarly, 70 per cent, phosphate at 2s 8d per ton would give a unit price of sd. If the New Zealand Government got to work it could get phosphates sold within itself at lOd per unit, and that would double the production of the country and benefit the whole community. Perhaps the significance of these figures does nob appeal to practical farmers as their importance demands. It is to be feared, however, that if 20s per ton for freight was added to 10s 6d on the cars, and 10s for mixing, sacks, railage, delivery, etc., another complexion might bs put upon the Florida shipments. This would not refer, however, to local phosphate rock, and, being abundantly supplied in this direction, it would appear that it might be placed on the market at a very much lower rate —made up —than it is at present—viz., lOd per unit. For instance, a compound having exactly the same composition as basic slag could be mads ,up at Milburn for the cost of burning the lime and the rock and crushing it ciftei excavation, and be sold to farmers at a profit at about 50s per ton. Whether it would have the same effect on the land or not remains to be seen. Mr A. H. Hall says: “Sometimes these rock phosphates are ground to a very fine powder, which is practically insoluble in water, but which does slowly become available to the plant in soils rich, in organic matter and well provided with moisture.” I here is evidently no reason why such a compound should not prove an acquisition. Many farmers find that the results obtained from manures of good organic origin, such as bones and some of the •manes, are better than those from mineial phosphates. But it is a case of comparative value. It does not matter what the origin of the phosphate may be so long as it is there, and good results are obtained from its use. The importance of a cheap supply of phosphoric acid cannot be too strongly insisted upon. It may be said to be the dominant constituent ot turnip manure, of barley mixtures, of all mixtures for leguminous crops and P as ' hires. Analysts are liable to conclude when examining the plant foods extracted by the different crops that phosphoric acid is Jess important than nitrogen and potash, whereas in actual practice the reverse is the case. The latter circulate better through the soil, and are more readily available for the plant than the former. Hence more phosphate requires to be used and it ought to be cheaper. It is not liable to be washed away, and if sold at a lower price larger applications would be made of it. Any balance not utilised by one crop remains available for the next. It has already been shown in the North Island that pastures and hay lands poor in phosphate of lime cannot support stock in a healthv condition. Much of the natural fertility of this country is being sacrificed bv the inordinate cropping demands which are being made upon it. Ne'dect of the law that the land must be fed is steadily reducing its productive power in the older settled districts. This is concealed over the whole Dominion at present on account of the number of new holdings which are being daily broken in from the bush, and keeping up the volume of export, and because the fringe of the North Island has not yet been touched; but the process is going on, nevertheless, in the south, and the high price of artificial manure fosters the deterioration and even desertion of lam! that should have provided homes for all time for a thrifty population. Mr Thomson also pointed out “that New Zealand imported yearly 100.000 tons of artificial manure valued at £574,000, of which 88,000 tons valued at £317,000 were- phosphate manures, which gave an average price to the farmer of £3 11s 8d per ton.” If 50 per cent, was added to the amount stated it would be nearer the price the farmer has to pay for his manure. No reference was made to the amount manufactured locally by the various companies; but that must be considerable. There are no potatoes, turnips, mangolds, carrots, rape, or other green or fodder crops grown in this Dominion without a considerable proportion of phosphatic manure. A really plump sample of wheat is hardly ever produced c-xcept on soil well supplied with phosphoric acid and iimo. Five hundredweight per acre of slag would provide about sufficient for a large crop, but the price is considered too high. Second class land in oats generally gets some assistance from tho same source, but not so much as it should, because their effect is not conspicuously seen till harvest time. They hasten maturity and favour the reproductive side of the plant’s development. Two hundredweight of superphosphate would increase the yield of oats five bushels per acre, and raise the whole sample to a higher grade. Larger applications than are usually given would be justified. The best results are obtained by slocking the soil with abundance of phosphate. the reason being that when superphosphate, for instance, is sown the soluble phosphoric acid in it is at once distributed and taken up by some base which refuses to part with it till acted upon bv the carbon dioxide of the soil or that exuded from the plant rootlets. The plant fibre must therefore be contiguous to the prosphatc of lime in the soil, and the fertiliser freely distributed everywhere. It would require a considerable quantity per acre to distribute a sufficient store of

phosphate to reach every corner. Our brightest hopes lie in the , intelligent use of artificial fertilisers, and the cheaper wc can get them the bettor. It is never good policy to deprive the crops of proper nourishment, but it is being done at present because the cost per acre is more than the farmer cares to risk or the selling price of produce warrants.