NITROGEN AND PLANT GROWTH.

Oamaru Mail, Volume IV, Issue 952, 7 May 1879, Page 3 (Supplement)

NITROGEN AND PLANT GROWTH.

{Chkfujo Times.) Year 3 ngn Liebig announced that plants, though deluded in a Pea of nitrogen, were not able to appropriate any of it directly. He taught that all plants must derive their supply of nitrogen from some simple nitrogen compound, as ammonia, or some s.iii. of nitric acid, as nitrate of potash or soda. This theory of Liebig went unchallenged for a long time, as did his other theories in regard to agricultural chemistry. To supply the demand of plants for nitrogen, the well-known salt, nitrate of soda, was brought from Chili, while nitrate or potash or saltpetre was manufactured from urine and ashes or obtained from caves in the earth. Most of the artificial fertilizers were appraised according to the percentage of nitrogen in the form of ammonia they contained. In order to show farmers that they were getting the worth of their money, the dealers in fertilizers furnished analyses of their goods, giving the amount of ammonia they contained. Surprise has sometimes been expressed that the application of so small an amount of a nitrogen salt should result in the production of so much nitrogen in the plants raised on land manured by the salt. Again, it was found that certain plants, as sunflowers, which contain much nitrogen, would make a fine growth on soil very deficient in this substance. Still the theory of Liebig that plants wero unable to appropriate nitrogen from the atmosphere was generally admitted by scholars in this country and in ifiuropo. Quite rec> n-v p d-stinu'iusli.-d French chemist has performed a series of experiments which seem to show most that plants do absorb nitrogen directly from the air by means both of their leaves and roots, under certain electric conditions of the atmosphere and soil. Plants added to their stock of nitrogen when grown in a soil that contained none, by being surrounded by an atmosphere of pure nitrogen, through which was passed a succession of electric sparks. As yet the chemist has made no practical suggestions in relation to supplying the requisite electrical condition to enable I plants to appropriate nitrogen directly from the atmosphere. The experiments he has made, however, throw considerable light on the action of certain fertilizers. There has always been a mystery connected with the action of gypsum and marl when applied to soils. They produce a greater amount of good than can be accounted for on ohemical or mechanical principles. It is possible that the application of these substances, as well as salt, lime, and ashes, may influence the electric condition of the soil so that nitrogen is taken up by plants through their leaves or roots, or both. Why certain plants rich in nitrogen, as cabbage and cauliflower, require frequent hoeing in order to make a rapid growth has never been well understood. It is possible that the friction produced by the movement of the hoe and the bringing together of different, substances in the soil may excite electric currents very favorable to plant growth. The subject is certainly of great interest, and well worthy of thorough investigation. <» A PLAN FOR PRESERVING CATTLE FROM DISEASE.

On the occasion of the present outbreak of disease among the cattle of Northern Germany, a correspondent of the ILonigsbnrg Land-und Fortswirthshaftliene Zeirung forwards to that journal for publication an extract from an old newspaper of the last century, in which are described at length the details of a process, by the employment of which the immunity of cattle from rinderpest and pleuro-pneu-monia is said to be secured with absolute certainty. When disease was raging among the Pomeranian herds in 1793, the whole of the cattle in a certain district were lost, with the exception of those belonging to a certain farmer, named Steincke. A similar circumstance occurred a few years later during the presence of contagious pleuro-pneumonia, Steincke alone preserving his cattle perfectly healthy, whilst all his neighbors had to deplore the loss of theirs. The matter was thought of sufficient importance to demand a Government inquiry, and a commissioner was sent down to interrogate Steincke on the subject. In reply he stated that he attributed the immunity his cattle had enjoyed, entirely to the precaution he had taken on both occasions of giving them regularly, while tho disease was about, an electuary of the following composition : —Two spoonfuls of tar, two handfuls of salt, one handful of garlic, one spoonful of motherwort, one of coltsfoot, one of horse-radish, one of burnt and ground juniper berries, and one of angelica root. The materials wero well mixed together, and a spoonful of the electuary thus made smeared in each animal's mouth daily by means of a brush. The antiseptic nature of several of these ingredients being recognised, the Government made known the composition of Steincke's mixture as wide as possible, in order that all who thought fit to do so might try its virtues for themselves. Many years afterwards, in ISM, the clergyman of a parish near Dessau wrote to the public journals, recording his experiences of a similar line of treatment during the war of 1813, when plague and other diseases were prevalent far and near. At the first rumor of their approach his father adopted the plan recommended by Steincke, and when in due course the plague made its appearance in his village his own cattle remained in perfect health, whilst those of his neighbors fell victims all around him. ARTIFICIAL MANURE.

(From Land and Water.)

The exhaustive experiments which have lately taken place on the experimental farm at Aboyne, under the professional charge of Mr. Jamieson, the eminent chemist of the Aberdeen University, furnish another proof that the emphatic opinions expressed in recent publications as to the superiority of dissolved phosphates, comprising dissolved guano phosphates, over raw phosphates are grossly exaggerated. The results obtained with the raw phosphates were hardly inferior to those of tlie dissolved, and the difference was certainly not such as to justify the increased price for the dissolved article as compared with the cost of the genuine raw material. It must, moreover, be remarked that a manufactured manure, as for instance the so-called dissolved Peruvian guano, must necessarily contain a large proportion of sulphuric acid, frequently to the extent of from 25 to 30 per cent., which thus reduces to the same extent the proportion of guano or valuable fertilising material contained in such artificial manure. In other words, a ton of so-called dissolved Peruvian guano will not contain more than 15cwt. Peruvian guano (supposing no other guano to be used), it being currently stated that with three tons of raw Peruvian guano four tons of dissolved guano can be produced. A3 the price per ton of dissolved guano, stated to contain 8 per cent, of ammonia and 22 per cent, phosphate, is £l2 10s, this price is paid in reality for loewfc. only of guano, the remaining scwt. in the ton being constituted by other ingredients of chemicals required for the purpose of manufacture. Thus the real price per ton comes out at £l6 13s 4d, whilst raw Peruvian Government guano, containing the same or even a fractionally higher percentage of ammonia, and also 22 per cent, phosphates, may be at present purchased at a trifle more than half that price, say at £9 15s 6d, buyers obtaining an :absolnte guarantee a3 to the genuineness of the guano, and ;moreover having at their command every means of ascertian-

ins: that they receive tlie guano as from the Peruvian deposit. Considering tin; ,iiiuvoi!ii'iir!u:ii;d experiments in Scow :, w,; not-d not deal any longer wit! sin- oiisclf its argument that the dissolved s<» much more valuable f.ian <:•»; genuine raw material they are .v"in, and must con line ourselves to 31l; ;i favor < f tlie dissolved article

: .;in lis liiy and powdery composition is oeri.ainh' a valuable quality. We leave it to farmers to judge whether they are prepared to iky for this solitary advantage :uone £(.! 17s 10d per ton more than they would piy for the genuine raw article. Another point worth mentioning in connection with the Abovne experiments is Mr. ii-sonV. statement that nitrogen ■done h "1 no t-liVut, but when added to superphosphate.-* it gave an increase per Scotch acre of from one to four tons on a crop of turnips, although it was afterwards found that ;he increase was almost entirely due to water. Tin s-', results, which no doubt further experiments will more forcibly bring into light, cannot fail to caution fanners against the now too indiscriminate use of nitrate of soda, the proper application of which ought not to go beyond top dressing for certain cropa when the plant is fairly developed.

... —O- -- THE FUTURE OP AUSTRALIAN FARMING.

(From the Australasian.) It must long have been evident to thoughtful and practical husbandmen that a change iti the agricultural system of Australia will sooner or later bo forced upon those engaged in the business of production. The general statistics of yield which are annually published are misleading unless they are closely analysed. The statement that a certain average yield of wheat has been obtained may be strictly true, but it not only doea nob reveal the whole truth, it is positively a sugrjestio falsi; to get at the real state of the case the whole of the returns need be examined, and these, as is well understood, are inaccessible to the public. We get, however, in the returns of our own harvest correspondents, and also in those of our Adelaide contemporaries, some very sound notions in relation to the effects of the practices now in vogue, and which pass for farming in these colonies. No real farmer can peruse a series of harvest reports -without discovering that if the average yield of any one cereal is maintained, it is not done by the land referred to in any previous series, but by the addition yearly made of new land, and the omission from cultivation of that which has longest been under crop. Hera in Victoria farming—and it was worthy to be called so—commenced on the southern seaboard. For many years a very fair imitation of the British husbandry system was carried on, and in the palmy days of the Port Phillip Farmers 1 Society many examples of the system were shown by members of that body. When the policy was adopted of giving away the public estate to all and sundry who would reside upon and exhaust its fertility according to terma prescribed by Act of Parliament, the old farmers, being no longer able to procure experienced hands, had, perforce to allow their lands to go back into pasturage, good or bad, as chance would have it. For a time grazing wholly took the place of grain-growing on these old farms, and the loss of the hands was not much felt. At length, however, it became necessary to renew the pastures themselves ; the grasses almost wholly died out, and the practice of breaking up and laying down grasses afresh every fourth or fifth year is now generally recognised by experienced farmers as an essential part of the new system. There is reason to believe that in the cooler districts the cultivated grasses would stand for many years, and, as in the climate of England, improve as pasturage with age ; it is certain that they will not do so under the want of systematic stocking which is prevalent here. Frequent shifts and understocking are indispensable to the maintenance of a good sole of grass. They are the key to success in grazing, even in ordinary seasons, and much more so when drought is present. Admitting, however, a practical necessity for laying down grasses afresh every few years, it is evident that the system cannot be generally adopted throughout the newer agricultural areas, or even in those selected at an earlier date, excepting by men who have capital at command. Successful management of grass land implies much subdivision (which iscostly), deep cultivation, and aB a necessary preliminary a liberal investment of capital. How, then, are those who are penniless, and who have also no knowledge of tho management of land —as is the case with the majority of new occupiers—to fulfil these conditions? And how in the absence of such fulfilment can the rapid exhaustion of the soil be stayed % The future of farming in Australia is by no means promising. In this Colony more particulary as much has been done as was possible to prevent the adoption and development of a rational system ; the law has prescribed tho coursa of cropping, and regulations have taken away from the selecting occupier the power to raise the capital which is indispensible to his success. There are, of course, men wiio will succeed in spite of all difficulties ; men who have not only superior abilities, but who possess advantages in respect of soil, climate, or proximity to a market, of an exceptional character. These may be left to themselves, but the majority of selectors are just now in a most critical position ; a few have thrown up their holdings, and have sought employment with men of mora means, whilst many would sell out and thus escape from their difficulties wera they permitted to do so, aud could they save a little from the wreck. The attempt now being made by the Minister of Lanaa to prevent tlie alienation of land acquired by selection is, from an agricultural point of view, a serious mistake. The absorption of two or three farms into one offers, in all the drier parts of the colony, the only possible means of enabling occupiers to work their land profitably. Between the Port Fairy soil and climate of those of. say, the Terricks and most parts of the Wimmera there is nothing in common ; they cannot be compared in any way, and yet the law has fixed 320 acres as the limit which may be selected and held by one man in any portion of the colony. But for the interference of the Minister, a great deal of the mischief and misery entailed by the limitation of area would be soon remedied, and the land be employed in such manner as would be most profitable to the individual, and incidentally to the State. It is time that the eyo3 of Australian Governments were opened to the evil of free selection upon the terms associated therewith in these southern colonies. It should be now clear to them that agriculture proper can have no part in the system, and that if tlie reduction of the wheat-producing areas to sterility is to be checked or prevented, it iB not a moment too soon tu commence a reversal of the policy which is leading to such results. PRINCIPLES OF CATTLE FEEDING. The most important condition of success exists in the animals themselves —it is the activity and training of the cjlls of which they are composed; and so, just as we have breeds of racehorses that have been trained for generations to ran, we have also breeds of cattle that have been trained for generations to store up the constituents of their food in the form of ... flesh and fat. And just as bertain as. ! -a jj racehorse may be injured by improper food, carej or training, ju3tVso-'surely will a steer, whether scrab or has been starved or stunted at any porioa

of its life, faO to fatten as pn>6teoly *» it veolcl if tin ctlls of it* body had been waqkrfy exercised by an abundant supply of food from the first day of its life. Again, an animal which hi* always received aa abundant supply of io>a, will mit and than *>ne that rw» ; it wilt probably not digest a larger percentage of tfc® nutritive constituents, as baa b«eo chimed, bolt the fact that it can ;«aft more and digest the same percentage ,0 an important «ne. There are, then, tw» reason* why the precocious breeds of •cattle are more profitable than others •viz., by eating and diireating the same amount nf food the cells «>f the body will store rip l a greater iptantity «s flesh »«»" %t ' and by an increased supply «>f f»"d e f"*. v are able to and driest more, thus laCitetjr adding to the farmer advantage. I>. K. Salmon;, in Country Gentleman.