NITROGENOUS MANURES IN NEW ZEALAND.

Otago Witness, Issue 3315, 26 September 1917, Page 11

NITROGENOUS MANURES IN NEW ZEALAND.

MANUFACTURE OF NITRATES FROM THE AIR. By Ax ExrERT. A good deal of misconception seems to prevail in respect to the great possibilities in the installation of a power-plant and factory for the manufacture of nitrogenous manures from the atmospheric nitrogen. Several articles have appeared in the press within the last couple of months wherein it was stated that a strong syndicate had been formed in Dunedin to rnanu-" facture such synthetic nitrogeneous manures by utilising water power obtainable in one of the sounds of the west coast. It seems that the project is dependent a good deal on the New Zealand farmer, who is to be invited to ; subscribe the necessary capital. Mr J. C. Anderson, who delivered an addreso about a month ago at the Clutha Branch of the New Zealand Farmers' Union, stated that the company would be a publio one, worked on a co-operative basis, and that it would take over £200,000 to supply the necessary plant, etc; The misconception seems to exist in failing to appreciate the very small consumption of nitrogenous manures throughout New Zealand. The consumption of manures In New Zealand should form a useful guide to farmers and would-be investors in this scheme. For the year 1915 the following manures were imported into New Zealand:—?-' Tons. Superphosph&tesi 54,300 Rook phosphates and guano .. 39,519 Basic slag 11,056 Total 104,875 Most of the_ rock phosphates imported were utilised in manufacturing superphosphate, and it is therefore probably safe to assume that the above total could bo increased by, say, 12.000 tons, making the Sand total of 116,875 tons as being the nsumption of purely phosphatic fertilisers. To this must b 9 added manure materials (by-products of the meat-freezing industry, etc.), and of these New Zealand imported during the year stated the following: Tons. Boned'ust and bona char. 10,436 Blood and bone .. .. 766 11,202 Meat works manures of New Zealand '. origin, say: 12,000 . 23,202 These manures arc chiefly valued as phosphatic manures, although their contents of nitrogen are appreciable, and perhaps average about 4- per cent, nitrogen. Of the purely nitrogenous fertilisers, which are practically all imported into New Zealand, the total amount would be about 2000 tons. Nitrate of soda and sulphate of ammonia are the chief fertilisers of this kind, and a good proportion of them are used only indirectly in tho fertilising trade. Potash manures, which are at present unprocurable owing to the war, were not used to anything like tho extent of phosphatic manures, the total imports of all kinds being n for the vear 1914 about 4500 tons. It will thus be seen that although the consumption of fertilisers in New Zealand has already assumed considerable proportions the importance of phosphatio manures completely overshadows the consumption of potassic and nitrogenous manures. There is tio doubt that as time progresses the use of nitrogen and potash will, increase, especially when the correct methods of application are moro widely understood by the agriculturist. Another pointof misconception is that these atmospheric nitrogen manures do not consist of the same chemioal form as tho more favoured and older established nitrogenous manures like sulphate of ammonia and nitrate of soda. Although large quantities of cyanamido are now made in Germany, Norway. Sweden, etc, the popularity of nitrate of soda, has never been displaced. Persons who have to handle cyanamide frequently raise objections owing to its caustic action and odour. Nitrate of lime, the other form of atmospheric nitrogen fertiliser, attracts moisture to a much greater extent than either sulphate of ammonia or nitrate of soda, and cannot be conveniently kept on most farms in consequence.

A great deal of prominence has been given sinco the outbreak of war to the production of those atmosphorio nitrogen manures; but it is a significant fact that Germans still cry out against the blockade because (amongst other reasons) it prevents them from getting suppl'es of nitrate of soda from Chile.

The cost of the necessary plant to manufacture these fertilisers would bo out of all proportion to the value of the commodity which would find a market ill New Zealand, and even if the material could be sold at £1 lQs per ton, as stated by Mr Anderson, most '-farmers would probably stil! prefer the nso of meat works manures, sulphate of ammonia, or nitrate of soda.

The utilisation of the- vast power that could bo obtained from the numerous lakes, fivers, and waterfalls of Now Zealand could be muoh better used for electrifying- railways, electric lighting, and for innumerable other power purposes in manufactures. The Board of Agriculture as well as the head? of the Agricultural and Public Works Departments have no doubt-considered this Bcneme, and the formation of a private company, financed by contributions from the farmers, would appear to be altogether premature and unjustified by the existing demand for nitrogenous manures. Although nitrogen is largely tho controlling factor in crop production in Great

Britain and Europe, it is at present phosphoric acid which is tho principal factor of fertility that concerns the New Zealand farmer. Evory farmer knows how essentia* somo phosphatic manures are for producing a crop of turnips, mangolds, etc., in many parts of the country. In tho course of time, particularly when transport, method of application, and gcnoral trade arrangements are improved, and farmers begin to realiso tho value of nitrogenous manures, the consumption ot these materials will surely increase.