MANURING FOR GRASS.

Auckland Star, Volume XLIV, Issue 156, 2 July 1913, Page 8

MANURING FOR GRASS.

WHAT TO USE AJHS HOW TO USE IT (By HERBACEOUS.) Can pastures be made permanent This is a question which is of great importance to farmers in many parts of New Zealand, and is one that can be answered in the affirmative, in many cases. It i= not of such importance in districts where cropping is carried on extensively, as there farmers break up every four or five years, so that their object is not so much to secure permanence of grass as it is to get the greatest amount of feed during the. time the paddocks are used for grazing. The object of this article is chiefly to deal with manuring permanent pasture rather than with short period laye. In either case, however, liberal manuring will pay.

In some of our lighter soils, before the practice of top dressing came into vogue, the trouble was to secure pasture that would last longer thai) three or four years. At that time the farme.had to break up fifty, sixty, or more acres, according to the size of his farm, and grow turnips so as to prepare his land for fresh seeding with grass. In most cases a third, or perhaps less, of the area would have been sufficient to provide roots for winter feed, but perforce he had to break up in order to get fresh pasture to replace his worn-out grass. Now, however, thanks to top dressing, he is not put to the expense of breaking up more than he wants for winter feed; he is also spared the cost of seed, a very serious item apart from the extra labour involved. Once a man gete a really good sole of permanent grass it pays him to keep it. I personally know of two paddocks, good alluvial soil, one of which has been in grass for about fifty-four years, and the other immediately adjoining thirty-five or thirtysix years. Both arc in splendid heart. Needless to pay. the land is of exceptional good quality, for it is only of recent years that top dressing began to find favour. But, though the land is undoubtedly good to have carried the sole till top dressing came in. it has been much improved by top dressing, the difference in the herbage after a manuring with slag being very marked in each field. But even on land which at one time was considered inferior, good grass can be seen which was sown as far back as twenty years, and which has been kept in first-class condition by liberal top dressing. Experiments carried out in Britain, the Continent, and here in Xew Zealand, on fairly stiff soils at any rate, have shown that one heavy initial dressing has been more effective and more lasting than two or more dressings at intervals—the several dressings aggregating as much as the heavy initial one. It must be borne in mind, however, thst these experiments have been made, as stated, on soils more or less stiff. lam not aware whether such trials have, been made on light or sandy soils, but it is one which is well worth making. If, say, scwt of manure at one application will give better results for a period of five years than 23cwt in each of two dressing at intervals of two years, it would be more economical to use the heavier quantity and so save the labour of a second sowing. Furthermore, the extra quantity of feed which would be given for the first two or three years from the heavy dose would make the latter method still more profitable, so that the experiment on light soils i 3 one which should be made.

In Professor Somerville's experiments,' made to supply information to the British Board of Agriculture, the heavy initial dose proved the more profitable over a period of nine years, during wiiicii time no second application was made to the plots receiving the heavy initial dose. It is true that his quantity was half a ton of slag to the acre, more than people here would care to put on, but the principle is the same. MAXUKES TO USE. This is not a matter of opinion or individual predilection, but one which has been demonstrated by actual csperiment. In most cases slag has unmistakably proved superior to every other phosphatic manure as a top dressing; there arc some instances where super and bone have done better, or either by itself, but euch cases are rare; but that they have occurred is reason for experimenting with these manures.

It may be mentioned that there are some districts iv which these trials have been made and the superiority of super has been proved beyond doubt. At Moumahaki and for a certain radius round it slag has proved inferior to super, but outside thie radius the former is far and away the better of the two. It is possible that on soils rich in lime super would prove the more effective, as in such a case an acid reaction might prove beneficial; that, however, is also a matter for experiment, for it is a fact that in some cases in the South Island a mixture of 6lag and lime, six cwt of lime and two of s-lag to the acre, gave wonderful results when used as a top dressing, the clovers and rye grass especially predominating. It is a curious fact that in some districts where lime has had no appreciable effect, when applied either as burnt lime or ground carbonate, slag, notwithstanding the fact that it contains, in addition to lime in combination, 15 per cent of free lime in the caustic form, gives much better results than super. In one district lime has no effect because there is already in the soil a superabundance, yet slag has proved for various crops the best form of phosphatic manure. Ail this calls for careful experiment on the part of the agriculturist. The best of our analytical chemists will not dogmatise in these matters. We are deeply indebted to the chemist for our success in every branch of industry without exception; and when these highly-trained men will not make a definite assertion or statement without making exhaustive experiments, how much more, therefore, Mould the layman make these trials for himself before accepting the dictum of others unless they come to conclusions from actual experiment ? Even then the condition? of soil on one man's place may be entirely different to those on the farm where the trials were carried out. It therefore behoves every man to put the question to the soil himself; if he does he will get an unfailing answer. While super is undeniably an extremely useful manure, there is, in my opinion, too much indiscriminate use made of it, for I know there is a close connection euper and sorrel. Though I have so far only mentioned super and elag as phosphatic manuref, there are others which should be ueed in making experiments—boneduet and guano; and in experimenting the various manures should be used separately and in coubinaxion. The time is coming -sben potash will iw«tote more extensreeiyneed than it is at present. Faianese scarcely realise nn|y-^nM»-jt. T ' f li w ' f * Tl T^ Tv r*

gen, but large quantities of phosphates aad pot»h as well. Sitrogen ie renewed by the dovene and other legumes, but not so with the other two. Where young stock are raised lime also is taken up in certain quantities: this, however, can be sufficiently replaced through the medium of slag. Potash can be applied in various forms, such as kainii, muriate, and sulphate of pot?sh, one cwt -of either of tne latter two containing a* much pure potash ac 4cwt of the former. It clovers are failing, the cause, probably, in most jcases, is insufficient soluble potaeh, and possibly a-Ifio a deficiency of lime; in such circumstances a mirture of slag and potaeh will be in most ess the most effective manure to use. AMOUNT PEK ACRE. This will vary with the class of land i and quality of the soil. On he*ry country of inferior quality 5 or 6cwt, or even up to half a ton of slag would be very effective. The very heavy dose hae been tried with profitable results on very poor stiff clay, while on some very ttiff country, not quite as poor, 6cwt itas given as good results as could be desired. On land in good heart 3 to 4cwt would be a liberal dressing. On light coil I should be inclined to put on -I or 3cwt at intervale of from two to three years, unless experiment proved that heavy dressings at longer intervals were more profitable. If super is used by itself, 2J to 3cwt should be sufficient, as so much of it is water soluble that a leseer quantity will suffice; but it must be applied more frequently I than oither elag, boneduet or guano. Lees bonedust than slag would be required. If bonedust contains about 22 per cent of phosphoric acid, and slag about IS, 2cwt of the former will contain within 1.12 units as much as 2icwt of the latter; but there ie this to be taken into consideration — slag ie much more quickly soluble than the hone. Guano ■has about half as much more phosphoric acid ac slajr. and about a-irhird more than bone, so that, theoretically, still lees of it should be used to get the came result; but practice noes not seem to confirm theory in this respect.

As regards potash, lcwt of kainit, or 2Slb of sulphate of potash, per acre, in conjunction with either of the other manure*, will bo found to give good results. I have known a case where hay ■had been cut continuously for ten yeare and carted off the paddock where 561b of sulphate of potash, in addition, to oewt of slag, restored the -worn-out clover. In such a case 561b would be quite little enough. TIME TO TOPDRESS. Autumn is probably the beet time, ac by putting it on in March there is every prospect of jrPtting a good growth during the winter; that is, of courae, in places where the frost is not severe. But even in such country autumn application is to be recommended, as the winter rains will have washed in and dissolved the 6lag, which will then be available when the plants begin to grow iji early spring. It it not always convenient, however, to sow in the autumn: in sucli a case winter or early spring sowing is advisable. As a matter of fact, we know now, as the result of experiment, that elag can be applied at any period of the year with advantage if there is rain soon after sowing.

A •final word of advice to farmers. Don't wait till your gra«e has nearly died out before top-dressing. Some men think when their grass is looking well, and the land ie in good heart, that topdressing is not retired. That is just the time to give it a little to keep it in such condition. 2cwi at that time will do more good than twice the quantity when the paddock begins to get bare. The wise man will not let bis land go back; rather will be strive to not tjnlv maintain but increase its fertility, for he realises that it will cost, far more to restore lost fertility than it would to maintain or even increase it. There is some land that ie so rich that it does not respond to manuring. I know of at least one such case, and, as the owner only fattens grown stock, he can go on fattening indefinitely without depleting ite richness. The only depletion is of nitrogen, which is taken up in the increased flesh, blood and tiesuee put on by the animate, but as this ie constantly being replaced by the clovers the lose therefore is nil