EXHAUSTION OF SOILS AND INTERMEDIATE CROPS.

Waikato Times, Volume XXI, Issue 1779, 29 November 1883, Page 3

EXHAUSTION OF SOILS AND INTERMEDIATE CROPS.

,Sib J. B. Lawks' experiments and researches at Rothamstead go to prove the serious loss of nitrogen and its soluble combinations, more especially in arable lands, through the washing down of these valuable fertiliseis beyond the reach of plant roots, aud ultimately into the , natural or artificial drainage channels. The source and conservation of nitrogen in soils have long been themes for discussion among scientists, and specially inter estmg to the agriculturist, because of the esteem in which manures with appreciable quantities of ammonia or other nifciogemnu? compounds are held, and necessarily the Larger expenditure involved in their purchase. Obviously there could be little advantage in the outlay in\ oh ed in investments in amniomacal or oilier easy soluble manures, for the conditions apply alike, it only a fleeting benefit can be lcaliscd. It must theiefore be a paramount objectof.thefannertonun.iiiH.se the apparently unavoidable loss by cat chilly observing correct methods in the application of fertilisers, and by adopting a course of cropping calculated to ensuie adequate pecuniary returns while maintaining the fertility of the soil Adverting to the great losses of nitiogen by heavy raws scouring out fallow lands, Mr Warrington, a pupil of Sir J. B. Lawes, in a lecture to an assembly of fanners at Chencester lately pi omulgated the startling doctrine that "as woods growing in stubbles would assimilate this nitrogen they should be allowed to remain," and endeavoured to substantiate the conclusion that autumn cultivation and, iufercntially, the practice of fallowing, aie mistaken practices. The idea, too, is tenable ; the weeds growing during winter would incorporate and store up nitiogen which land denuded of vegetation would lose, but the disadvantages of allowing tliem toiemain immeasuiably counterbalance the saving in nitrogen and other soluble plant food. Many of the weeds would perfect and shed their seeds, and all would strengthen and develop m io>>t growth, thus the land -would in a shoit time become hopelessly foul. Eveiy piactical farmer knows with what facility autumn tilled lauds can be cultivated m spring in compaiison with those that have remained in stubble o\ or winter. On the former a lino tilth can be obtained which is impossible in the lattei, unless at the expense of eonsitlciable extra labour. Moi cover, the weather is precarious in spring, and most unfavourable for clearing weeds, which at that particular .season it is almost impossible to kill out, so that in piacticc it would be found by those foolish enough to make the experiment that the e\tia cost of labour would pro"ide nioic than an equivalent of fertiliseis to those lost tlnongh being canted awn} by the rains. The pioper keynote has been stiuckbyan English exchange in commenting on the lectuie lefened to. " The most rational deduction from Sir J. B. Lawes' reseat ches consequently point in the reveiso dhoetion. Seeing that there is this dangci of the mtiates I being cairied oil by heavy autumn niins, the surface dealings of stubbles should belnuricd on eailici, with the ultenoi object of ciopping with tiifolium, rye-, wintei bailey, winter oats, or vetches— something to alloid a far better winter green covering than weeds, and quite as effective in sending down the loots of plants in search of the endangeied tieasuie, and incorporating it for active service, and when it is considered that these are matiiied sufficiently eail) in the year for a crop of swedes or common turnips to follow, an impoitant gain seems capable of being .seemed tlicieby. Properly conducted, such a s\. stein could not possibly fail in enhancing voiy materially the productiveness offaims." This is precisely thoeoutse weha\c so repeatedly recommended for adoption in New Zealand, where it could be carried out much moi e successfully, and with greater facility, than m < 4ie.it Britain Farmers of the last generation used to apply the term "stolen oiops"' to i ape, imisUid, stubble turnip, wintei oats and barley, vetches, and other produce ot the same class when made to dovetail in between wheat and roots, and while the farmer was enriched the land did not suffer. Here our winteis, are short, the growing season more prolonged, and a wider .selection ot plants to choose from theiebv atlouled, whose habit of growth would suit the particulaily puipose intended. According to the new theory fallowing is not an " unmixed good," but we cannot j_o the length of depierating the piactice as an evil one. It atl'ouls an oppoitnnity of cleaning foul lands, the soil is exposed to beneficial atmospheric influences, fresh action is stimulated, new combinations formed, and a supply of plant food piovided and stored up for succeeding crops, and although there is undoubtedly a wa^te of mtioyeiious constituents practical evpeiienre has proved that there aie moie than equivalent gains. But >\ c hold that all the advantage of fallowing may be secured and the land tuine 1 to pi oh" table account at the same time. Both in theoiy and practice the better comsc will be found in cultivating some crop ot l.ipid growth— in drill if the land be foul, otheiwise broadcast, and the value of which for stock food will repay the cost. With modern appliances even the moat obdurate land may be woiketl to immediate profit. We have been recently informed by a Southland settler of the method he has adopted this spring with " first furrow" land newly turned up. As the tussock was veiy rough when ploughed, two strokes of the disc harrow are ' necessary, the second crossing the first ; then Cockwerill's cultivator follows, and this leaves a fine tilth, and an excellent seed-bed for turnips or rape and mustard, broadcast. In this way the disintegration of the soil will be greatly promoted, the growing crop will arrest and assimilate constituents which we learn are extremely liable, especially where rains are frequent, to be wasted or absolutely lost. We may not with impunity ignore the teaching of science in this matter, for the Rothamstead experiments have clearly domon.strated the loss to the arable lands denuded of vegetation. The obvious and wiser course will therefore be occupy every available perch of land hitherto, on almost all farms, allowed to lie idle, with useful crop. Everything in the shape of stock food so grown can now be utilised profitably, and at all seasous ; and we are glad to learn that; efforts have been already made in this direction this season. So early as the second week in September we had information of sowings varieties of cabbages, and of cabbages and turj^tps alternating, with the view of pro/vMjng sheep food during the summer. i Extra food for sheep and cattle does not r mean keeping the stock as ordinarily understood, bur, the fattening or keeping them in high condition. In regard to autumn sowings of intermediate crops, the English journal already quoted, under date Ist October, says: "There are thousands of instances where surface cleaning itself has been effectually brought to a termination, and the land is now being re-sown with rye, winter barley, and vetches, to form winter green crops for consumption in the ensuing spring or early summer." Those who are sceptical as to the success of winter green crops will learn from this that it is a course commonly practised in Great Britain for many years by intelligent farmers, and they will further be assured of what may be safely undertaken here, up to a season corresponding with the English October. Originating in a commou practice of growing mustard, rape,, sainfain, cereals, &c., for the purpose of ploughing the crops in as fertilisers, as a better experience of their value was acquired the farmers in the Mother Country turned them to more profitable account as stock food. , With similar^,, grow^,j?rops New Zealand farmers will have a provision for their stock which will make them independent 6i a. backward or. untoward spring, and which will enable them to realise the

high prices which invariably prevail at this season of the year. The crops are literally the most economical that can possibly be grown, while we have undoubted authority to the effect that, independently of the manure made, the after-condition of the land is better than if it had laid in stubble during the winter, or if cultivated, in autumn and left uncropped, and the contingent loss of nitrogenous and other soluble constituents of plant food. The economical production of food for stock has now become a vastly moie impoitnnt question with New Zealand farmers. In other countries) with long winters or the reverse, prolonged droughts in summers many devices must be had recourse to, all ot which involve considerable expense, in order to tide .stock ()\cr the trying &cabons>. Here we expoiienco no biiuh dia\\ backs, and may, if we will, have a continuous supply ot gieen stnfT which cm be inexpensively fed off ■' on the foot." Ensilage may continue to e\cite controversy among larmcis in less favoured countries, but with oui facilities for the giowth of stock food and the pi ices obtainable for meat, much as they have lisen, the subject at present must possess but a veiy occondaiy interest for us. In conclusion it may be desirable to point one that the Rothamstead teachings suggest the obscivance of a mlc to bo observed in the application of most of the artificial manures now so largely used. Clearly they should be incoi rotated with the soil as near as possible to the suiface 01 in proximity to the space winch will be pcimeatud by the rootlets of the crop, otherwise the lams will cairy down beyond the i each of the a\ owing plant some of the uiobt \ alual ilc constituents..— Witness.