NARI AND OCEAN ISLAND PHOSPHATE.

Otago Witness, Issue 3571, 22 August 1922, Page 12

NARI AND OCEAN ISLAND PHOSPHATE.

COM 12 TO STAY. At the. recent conference of the Council ©f Agriculture the following paper was read by Mr A. F. Ellis. New Zealand Commissioner for the British Phosphate Company, end is of interest to all likely users of Nauru or other phosphatie fertiliser: The bonolits arising from using phostobatio fertilisers on our New Zealand soils Save been so fully demonstrated from time

to time that the fact hardly requires stressing. It will generally be agreed that, under most of our agricultural conditions, tlie farmer cannot afford to put in crops without them, and in many districts topdressing is equally necessary. It is evident that phosphoric acid is the limiting factor as regards our capacity of production, and, fortunately, such fertilisers are cheaper and more lasting in their effects than nitrogenous or potassic. The action of phosphoric acid on plant growth has been dealt with fully from time to time by competent authorities, and hardly calls for further reference. Its great service in bringing on the growth of legumes with their wonderful property of absorbing nitrogen from the atmosphere and storing it up in the roots for the benefit of grasses and other crops is now fully recognised. Probably this is one of the most important factors in the beneficial results obtained from top-dressing our grass lands. The fact that phosphatio fertilisers are supplied in three different degrees of solubility, however, calls for some comment; a good deal of misconception exists in this matter, and one frequently hears of the less suitable fertiliser being selected for certain purposes. To put this matter in a concise form, and avoid confusing technical terms, the following appear to be the general characteristics and conditions under which the various phosphatie fertilisers should be used: — —Water Soluble Phosphate.— The only form this is supplied in is the well-known article, superphosphate, the quickest in action of all phosphates, and particularly adapted for (Topping, by reason of the way the young plant is helped on. Its wonderful effect on root development, and iri hastening the maturity of tho crop, leave it without a rival in these respects. Where soils are more or less acid, particularly v/lien the super is used for top-dressing, it is advisable to use lime also, as this fertiliser is an acid one. —Citrate Soluble Phosphate.— This is usually supplied in the form of basic superphosphate, basic slag, and finely ground raw phosphate. Of these, basic superphosphate may be considered the quickest in action, and us regards percentage of phosphoric acid is somewhat higher than high grade basic slag. Being an alkaline fertiliser it can be used with advantage on acid soils, and many authorities hold that it is tho best article to use for topdressing, particularly where the rainfall is not very high. Basic, slag, if prepared under the Bessemer process of manufacturing steel, is fairly quick, and gives good results, but this process has been superseded in England and some other countries, by the “open hearth” method, which yields a much lower quality sing both as regards percentage of phosphoric acid and citrate solubility. Sonre of this “open hearth” sing is coming into the Dominion, and care should lie taken to make sure that it will compare favourably with other citrate soluble phosphates as regards results. In

any oase, even high grade basic slag contains leas than half the percentage of phosphoric acid that finely ground Nauru phosphate does. In the latter, a smaller percentage of the phosphoric acid is citrate soluble, and this has led to much misconception as regards its utility. The analytical process of estimating citrate soluble phosphate was first introduced as being the nearest approach to w-hat actually takes place in the soil when a phosphatie fertiliser 13 applied, and it was therefore considered an authoritative test a.s to the manurial value of the fertiliser. But of late years it is becoming discredited in this respect, and it has been demonstrated repeatedly by field tests that phosphates not highly citrate soluble, but high in phosphoric acid content, have given as good, ana frequently better results than a fertiliser containing more citrate soluble phosphate but a lower total phosphoric acid. The reasons for this are not difficult to arrive at. Many of our New Zealand soils are more or less acid, and this acidity is the main factor which renders the phosphate available for the plant, thus doing in slow degrees what the sulphuric acid does rapidly in the process of manufacturing superphosphate. The phosphate, while taking up the acids of tile at the same time counteracts the acidity to a considerable extent, in the same way that lime does, and thus further assists towards establishing fertility. Recent experience in the Auckland province has demonstrated the effect- of soil acidity on raw phosphate very forcibly. It has been found that when mixed with finely ground limestone, the phosphate has not given such good results. The reason is that the lime neutralised the soil acidity forthwith, thus counteracting the conditions wliich would have rendered the phosphate more readily available to the plant. The best test therefore for citrate solubility is the actual use of the fertiliser in tho ground, for the chemist, cannot produce in the laboratory the same conditions that prevail in the soil. This term is misleading, for though tricaloic phosphate is insoluble so far as pure water is concerned, when applied- to the soil it encounters different conditions. The soil waters contain carbon dioxide and organic acids, which slowly but surely on the phosphate. The principal jphoephatio fertilisers in this class are finely ground Nauru, basic slag and boned'ust, though the value of the last-named is enhanced by it,3 percentage of nitrogen. Phosphatic fertilisers containing a high percentage of insoluble or trioalcdo phosphate can be used! to beet advantage for top-dressing on acid soils, particularly in districts where there is a good rainfall; tho latter factor is a very important one. Without the rainfall the phosphate may lie for some time practically inert in the soil, but of oousre the process of rendering it available starts as soon as rain sets in. Soils which are rich in humus or decomposed organic matter, respond readily to this class of fertiliser. As these so-called insoluble phosphates are slowly soluble, the benefit from using them extends over three to four seasons, so that for permanent improvement to grass lands they may be considered quite suitable. It is very necessary that the materia! should be ground to a very fine state of division, at least 80 per cent, passing through the standard sieve of 100 holes to the linear inch. These fertilisers should be applied preferably in the late autumn or winter, in which case the plant has a longer period to draw its requirments of phosphoric acid before the spring conditions set in. If applied in the spring whon immediate action is necessary, this can be obtained by adding a proportion of superphosphate, say one part of super to two of finely ground Nauru. This mixture is very useful in many ways, and may be used for cropping purposes, as well as top-dressing. The water soluble phosphate gives a quick start to the young plant, and as it matures, tile lees soluble phosphate can be dealt with. Capable of Fulfilling All Requirements. It will be seen from the foregoing that Nauru and Ocean Island phosphate is capable of supplying all requirements as regards phosphatie fertilisers. If a quickacting phosphate is required, superphosphate is most suitable. If an alkaline fertiliser, suitable for top-dressing any' soils and safe for cropping even on acid soils, is needed, basic superphosphate is most suitable. If permanent benefit to grass lands is wanted, and provided there is a good rainfall, finely ground Nauru with its 84 per cent, of tiicaleie phosphate, may be expected to give good results, particularly if the soil is more or less acid 1 and has a good percentage of humus. Finely ground Nauru will supply phosphoric acid cheaper than any other form of phosphoric fertiliser without exception, and though there is some adverse comment from sellers of other fertilisers as to its solubility, there is little doubt but that all the phosphoris acid will be available for the plant within four years’ time. In the manufacture of superphosphate and basic superphosphate the high quality of Nauru and Ocean Island phosphate leaves it without a rival, and at the present time practically all of those fertilisers used in the Dominion are manufactured from the deposits on the two islands. Owing to its high grade superphosphate containing 45 per cent, water soluble phosphate is placed on this market. In England the usual grade of super is 30 per cent., and the saving in freight and handling charges to the Dominion farmer by using an article containing half os much again phosphoric add is obvious. In districts where railway and other transport charges are high and roads bad, it is of particular importance to use tile highest, grade fertilisers. With regard to the finely ground Nauru, it has a competitor in basic slag, for which there is a considerable demand. notwithstanding the fact that experiments conducted in certain localities under the supervision of the Department of Agriculture, have demonstrated that results obtained from finely ground Nauru even in the fist year are ahead of those obtained from basic slag. The fact that Nauru contains more than twice as much phosphoric acid compared with even high grade basic slag leads one to confidently expect that, in the second, third, and fourth years after application, Nauru will still be ahead. That, of course, remains to ho soon, and the’results which the department will supply in due course will be eagerly looked for. —• Question of Price of Vital Importance. The question of price is naturally of vital importance. In England basic sing being a by-product is sold to the farmers at less than half the price obtained there for finely ground Nauru. Naturally its use is strongly advocated, and undoubtedly

it is a cheap form of supplying phosphoric acid in that oountry. But in New Zealand the position is reversed, as basic slag costs more than finely ground Nauru, even though it contains less than half the percentage of phosphorio acid. The prices of the two articles as being retailed on the Auckland market compare as follows: Basic Slag.—l 3 per cent R2 05—equal to nearly 40 per cent, trioalcic phos. at £6 10s per ton; cost per unit of triealcie phosphate, 3s 3d. Naum Phosphate.—B4 per cent, at £5 17s 6d per ton —cost per unit of tricalcic phosphate, Is sd. The difference in favour of Nauru is therefore Is lOd per unit, or on « perceniage of 84 per cent, tricalcic phosphate £7 14s per rein. It may be taken os a general rule that where basic slag gives good results, finely ground Nauru will also be successful, as similar soil and rainfall conditions are suitable for both. It appears, therefore, that if through inadequate rainfall or lack of humus in the soil, satisfactory results are not obtained from (he finely ground Nauru in certain localities, it would point to the advisability of using the more soluble phosphate ior top-dressing, basic superphosphate. Some other competitors with finely ground Nauru in the New Zealand market are Beveral island phosphates, ranging about 30 per cent, to 65 per cent, tricalcic phosphate. Though these are of low quality, several thousand tons are imported annually'. The article supplied from, one of the islands is so low in tricalcic phosphate that one ton of Nauru is equivalent to about three tons of the other. The Dominion's Quota. — Under the terms of the Nauru agreement the United Kingdom and Australia are each entitled to 42 per cent, of the output, the New Zealand quota being 16 per cent. During the first 18 months under Government ownership, 554,656 tons of phosphate were shipped from the islands and distributed as follows:

The very low proportion used in the Dominion is to some extent accounted for by the fact that the various fertiliser manufacturers at that time had outstanding contracts with other suppliers for their requirements of rock phosphate. For 1922 New Zealand is doing much better, and about 45,000 tons will be used here as against 21,626 tons for last year. But we are still far behind our 16 per cent, quota, which on an output of 400,000 tons per annum from the two islands would amount to 64,000 tons, and this quantity would be readily absorbed here if it were not for the fact that the Dominion has unfortunately become a dumping ground for much lower grade phosphate from outside sources; the sale of those reduces the demand for tho high grade article from Nauru and Ocean Islands, thereby reducing the output from those two islands and retarding further reductions in our selling prices. If the Dominion farmers were to use only the various fertilisers prepared from Nauru and Ocean Island phosphate, whether in the form of superphosphate, basic superphosphate, finely ground raw phosphate, or a mixture of the first and last-named, they would not: only be using the highest grade fertilisers obtainable, but they would be helping materially in bringing about further reductions in selling prices. This applies not only to the working costs at Nauru and Ocean Island and other overhead expenses, but also to the fertiliser works in the Dominion which are mostly new and quite up-to-date. They are working on Nauru and Ocean Island phosphate now, and only require a big turnover to reduce their working costs to a minimum. Another Important Aspect. There is another important aspect of the case which should not be lost sight of. Under the terms of the Nauru agreement, while the Dominion is entitled to 16 per cent, of the output, the proportions allotted to each country are to be re-adjusted at the end of each five years, in accordance with the quantity used during that period. Should we fail to" use our 16 per cent, quota during the first five years, and we have already fallen behind a great deal in the first two years of the currency of the Nauru agreement, the Dominion would only be entitled to a correspondingly reduced quantity for the subsequent period of five years. There are three years left in which w-e can make up our deficit, but failing this, New Zealand would not be entitled to 16 per cent, of the output as is the case at. present. The world’s consumption of superphosphate doubled in the 10 years preceding the war, and it may be expected that the same increased demand will take place here. If through using large quantities of low grade phosphate from outside sources this country loses its right to an adequate proportion of the Nauru-Ocean Island output, it will be realised when too late that a very serious mistake has been made. There is sufficient of this wonderfully rich phosphate on the two islands to last several generations, and owing to their proximity to the Dominion, if it'is more generally used, it will be possible to place the material on this market at low prices. But that will avail nothing if the Dominion farmers, through apathy or shortsightedness, allow the right, to an adequate proportion of the output to be lost. The remedy is obvious, and may be placed in a nutshell —use the Dominion’s phosphate, prepared at works within the Dominion, and no other—that is the safe policy leading up to a rename supply of highest quality fertilisers obtainable at, lowest prices. While this arrangement regarding the rc-adjustment of the proportions allotted to the three countries would work adversely in the event of the full quota not being used in the Dominion, on the other hand it would work (o our advantage if. as might reasonably bo expected, the Dominion takes more (ban 16 per cent, when it is available, which at present is the case In all probability the Dominion consumption of high grade phosphate wi.l he 100.000 tons per annum m a few years, for we may confidently expect a continuation of the closer settlement policy, resulting in the taking up of many d our idle sovom, class lands, which only require cheap phosphate and railway facilities to transform thorn into prosperous dairy farms. Under tho terms of the Nauru agreement it. would be. possible to yet, 100.000 tons per annum mid even more, without paying any further sums towards (ho capital invested in the business, but il can only be arrived at if (Vie Dominion farmers whole-heartedly eonline their fertiliser purchases to Nauru phos-

phate, whether in the form of superphosphate, basic superphosphate, finely ground raw phosphate, or a mixture of the first and last. The Government went into the Nauru arrangement at (he expiess wish of the agricultural interests of the Dominion. It assures (he supply of the highest grade phosphate for this and future generations, but it is necessary for farmers to abide loyally by that arrangement, otherwise other countries and nor New Zealand will be the ones to reap the benefit. Tangible Benefit Looked for from the The Dominion having invested nearly £600,000 in the Nauru and Ocean Island phosphate deposits, it is natural that Borne tangible benefit is looked for from the investment. In this connection it waa stated recently in the press that Australian farmers have already effected savings to the extent, of about £2 000.000 by using Nauru and Ocean Islam! phosphate since the business was purchased by the three Governments. This highly satisfactory result has been effected because in Australia the merits of a hieh grade article are fully recognised, and there is practically no demand for any other phosphate. For the first 12 months under- Government control, Australia took no loss than 265,000 tone from Nauru and Ocean Island. In the Dominion tho principal benefit to the farmers has arisen from the tangible reductions already made in the prices of phosphatie fertilisers since July 1, 1920, when the business was taken over by tie three Governments. At the time super was retailed at £8 10s. and finely ground raw phosphate at £9 12s 6d in the Auckland market ; the retail prices now are £6 and £5 17s 6d respectively. The commissioners responsible for the working of (he deposits expect to make further reductions in the price at. which they sell to the countries concerned, but this depends on the output obtainable from tho two islands. To work them economically they must export 400,000 tons per annum, and up to the present this has not been possible, owing to the fact that this quantity of high grade phosphate cannot be sold, in the present siate of the fertiliser market. - Progress of Operations at Nauru and Ocean Island Since Change of Ownership.— The industry at, Nauru and Ocean Island has now been under Government control, through the Hoard of Commissioners, for just over two years, and it may be of interest to touch briefly on the progress of operations there since the change of ownership. The best test of efficiency is naturally the amount of phosphate exported per annum, though lire weather and other local conditions have a certain bearing on tlie subject. During last year a total of 394,000 tons were shipped from the two islands; the best previous year when the Pacific Phosphate (. ompatiy owned the business was 1913. when nearly 339,000 tens were shipped. This record has therefore been broken by about. 55,000 tons. A record day’s work at shipping was put up at Nauru when 2189 tons were shipped to the DeVungra. This quantity was all lightered off in surf boat’s carrying about three tons, which have to be towed off to the vessels by oil launches. These instances of efficiency at the islands afford evidence that the work can be done, so far as the islands are concerned. As a matter of fact we load the steamers much faster than they are discharged in New Zealand, which is good evidence as to the need of improved methods of handling the material here. Since coining under Government ownership, up to June 30 last, the total shipments from the two islands, the amount* taken by the three countries interested, and i heir respociive percentages are a* follows: —

This Year Smaller Shipments Expected. This year it is apparent that shipments will tie considerably lower than last year, ns the Commissioners are experiencing more difficulty in selling the output, owing to tlie slutnn in the fertilised trade in the United Kingdom, tho Continent, and Japan. For this reason we have repeatedly been without steamers at the islands, and on two occasions our storage bins were so full that the phosphate raising and drying operations were brought to a standstill. Ii is hardly necessary to point out how adversely this acts on our working costs, and particularly when the business has io pay interest on the large capital invested by the three Government s. With a view- towards further reducing our working costs in various ways, and strengthening the position at the islands, tho Commissioners are now- calling for tenders for the erection of a modern shipping plant at Nauru on the cantilever arid rubber belt conveyor principle. This would dispense with (no present laborious and costly system of lightering, and would permit of ' shipping at the rate of 500 tons per hour, tints loading a 6000 ton steamer in a ilav. Tlie erection of this plant will take probably two or three years. Alien it is going, and the production of phosphate is up to 'saw 500.(XX) tons per annum, the effect on selling prices to the countries concerned will he very silt isfactory. Whue this cantilever is the main development under consideration, other material improvements arc being made, (he prinlipal one so far being the purchase of a new steamer for the trade. She is named the Nauru Chief and is now on her way out from England, via Panama, and is due at the islands towards the end of next month. She will ho particularly suitable for doing tho difficult work in connection with tho deep sea moorings at the islands, and for recruiting labour. Some good passenger accommodation has been installed for the benefit of the considerable minutely of pas-cen-wi-s who travel between the islaiidf and Australia, and also cold storage chambers for the carriage of frozen meat. etc., to the islands. The vessel will carry about 3750 tons’ of phosph e. and will thus he profitable as a freight earning proposition, while her other eoiivenienees will render her of great value to tlie business. 11l conclusion. 1 may say that the Nauru and Ocean Islands Phosphate industry under Government control is progressing Satisfactorily, but as the New Zealand representative on the Board of Commissioners. 1 consider it is my duty to point out that the Dominion is not receiving

bo full a benefit from the investment as might otherwise be the case, and its future interests are being prejudiced because the New Zealand farmers are not fully acquainted with the position. The remedy, as has been already stated, is in the farmers’ hands, and it is earnestly recommended that the matter should receive the attention of this representative gathering with a view to improving the position.

Tons. Australia . .. 867,496 United Kingdom . .. 32,300 New Zealand . .. 29,760 Other Countries . .. 185,110

1 S c fll 1 tIII Australia .. 437,200 CO. 2 42 New Zealand 66,600 7.7 16 United Kingdom 32,300 4.4 42 Other Countries 200,810 27.7 — 725,910 100.0 100.0