EXHAUSTED SOILS.

Otago Witness, Issue 1585, 8 April 1882, Page 6

EXHAUSTED SOILS.

It is a fact established beyond doubt the^t , any soil, however rich, will, by a pro.cess of con-* •: tinued cropping, become utterly ' exhausted ; ? that is, 1 if the crop is not consumed on v the t ground, or a due compliment of it- returned to the soil in the shape of manure. ' It is 'principally owing to the loss of the mineral properties of the land that this impoverishment takes place, and also, though' in a much smaller ' degree, to the consumption of nitrogen from the' s"oil.< But'it us also a^ell-known fact' thai'* long after it has been found impossible to .Taise • one kind 'of crop a'difforent<Bpe"cies of grain' 6r . root may be profitably grown for a number of seasons on the./famesoil.. ,It is also.know.n that sonic plants, such as the, different clovers aud 1 grasses, 1 the ro.ots of which penetrate to a great, depth, have the property of searching for^heiri food, as it were/ and <■ 'they t bring up ,fromi ! the subsoil the materials wherewith to enrich the surface soil. From .these few simple facts 1 it must be apparent' that' by a judicious succes- ', sion of crops the soil can be made to' retain its fertility for a considerable number of- years, - and 'as soon as the capabilities of a certain kind . of soil have been ascertained it will be a work , , of little difficulty to mark out the rotation best suited to that particular description of soil. This system of renovating, or perhaps we should say supporting, the soil may be, called, the natural, 1 method. But even tlaß .system, however judir cious, would eventually leave the soil- in .anything . jbut )a » rich « condition, while ;. in many*-. < ■ the yields would be reduced to^a-^ , minimum after j/fche' first* few fcrpjisi had been .taken off "th&tfand. .( In'ic6nsequehce .of. thisf "agriculturists" ' hayg -,to ft resort to artificial 'rateanavof .restoration, such as manuring, sub- [ soiling, draining, &c. Among the more im- ! P9rtant.of"sth'e3e,(.m i ethQds.fl,rp J ae_ep-.gk).ughing,i /gubsoiling, and draining.; Lin I , many placeß.m , tliis province these fertilising agents should precede even the application of manures, for in some of the stiff hard-clay subsoils there is often a quantity of material locked up that would supply the most important crops with food for years to come. In this respect another fact should also be borne in mmd — viz., that even though 'a soil may be extremely rich in the chemicals essential 4 for c the* production of. crpps, these materials may not be properly dis-" tributed throughout the^ , soil. Hence ithe necessity for- J| pldughirig*' arid**- harrowing -several times before the soil can be raised ; to its maximum fertility. This kind ibf, soils we may call infertile for they are those^thajtf cannot (produce crops, unless •mechanical operations are 'brdughVto bear "on .them. There are various methods besides , those already mentioned-,- whereby they can be improved, such as limeing, paring and burning, and. ,tr,ertching; <,Wa, ,ca^ot,^-h,pwover, expect that ,any „,0-rie of Jhese, methods FJlljbe 'generally.a dopted by 'our I ' 'Colonial farmers while labour ' is n £o '-'scarce) 'therefore 'weV'will dfrect our,^ attention sttfv?the >moreU<practicable methods;! ih^i ■ f-rv/i v • -v v »r, - ' |jPromine.n,t amopg tbese^meijhMs, as .wp.haye already^mentipnedjjs' phughmg. ,/Np'^'ni'any persons' ima J girie l tl\at' ploughing* is*"a v&ly'e'aßy aid simple J) matfcev; ''and 1 thafr'sV^ng, "as^the ground ;is'i turned A.oyer, ,the ? ends fqr{ which oploughing> tf >vasr instituted,, have bgen,. accomplished.. tiie Mnd^' THefe'-are many way's .of ploughing, aha th&re'ip a' Tight r a| well'a's'a wrbri^ way; We'-haVe Knowtfarufers td'lea've .their ploughing tiltafanon irntho ••season, f.thejr^ubie-fujrpw ploughr>cry,,j'gee, !( l h9J;,P.?bbi^ v.,and ,walk r6und .theirs nejHj.witb their hand^ 'in' their rackets;' ' *' T.he'se men'are fta&'farmers!' o ''" They surely ftaiV6'ho"^nowledgQ' tHafcttheJmechanical 'operation*, of ploughing jis,. performed |or v the purpose. of jiurning^ov.er y the £o.a,,no>t #nly for the purp.ose"pflopsening it,;but'alsb for exposuig it to the 'action' of tKe'WeatEerV" This l,';indeed,l,';indeed, isthe^principal objectifm^plbughihg'j'and ttp reap theiifull benefit;- <.tb'e jtandj should )be turned over as early, as,pp ( Sßible,.in}she year, r so cthat it may be .thoroughly" pulverised" by' the . frost and rain. Frost js , the % priricip'al ' agent in effecting this pulverisation' bfUKef soil, and the greater, the isuuface 1 exposod,to it the better I will this^be aQpomplished.^i.lf^the-.grqundis ploughed up in autmnn, the |frpst,,has' time to .penetrate the largest masses of soil, and as the moisture becomes frozen the mass expands and , crumbles away, so that by the time the warm weather setsin the land isleft in a finer state than - it could be reduced to by any artificial means. t Q&e effect of aubsoiling is- much the sanie; and Upother advantage is also gained by it, inasrpu.qh, as the surface-water is carried away and the. top soil thereby becomes less sour. But we have now sai4, a good, dea,l,on this subject, " v and must hasten bn-t'o 'method ofre■.eporing exhausted soils — viz:, that of manuring. . \ There> are 'few, soils, however/ rich,;that will? (produce several kinds of .crops with the sames . uegree.,of ■ abundance,' and .the only way to t a c-V icpmplish.thj^ issby tb,e application, of manpres/*f One, soil may r grp ( w a very gop'd'crop of wheat and *at jth'e'" same time be lin the pVpperties, 'essential' 1 to .tHe growth "'of' "even M a' ] fair crop .bf ', turnips; > " A' complete '. soil'/-'- sayS a )well-known author,? "is; s one , ; that will I , produce with-almost'equal luxuriance; > every kind of cultivated crop., -; ,In aisoil of this.jkind the constituents are so ,prop,prtioned,'thatj r • neither of them .abounds to so'greatran'eyteht * afe.to-interf.ere ,with the vigorous ,growth pt r any,, .liind ,of , plant, while, at the same tim'ej'gvjer^. material reqWecTb'y'each '4ultiva'ted •plants 1 present in sufficient quantity 'to admit 'of its^ luxuriant* growth. 'Were all=s6ils tof-thisis dharacter, the farmer might raise his corn, andrr r^ar his 1 cattlev with as much ease-a'a soiriel^person? ignorant ,cf agricultural -purfsujJaEj seem to imagwe/,'^ ..;■ t) ; »,/ . r t , ,' , , ,", b J}f , But suchf rapid* strides have within the pasty few years been made in agricultural 'chemistryj , , thatf^armers can, after having ascertained th^ . Composition ,of .the soil, make it grow, almqst,* any /crop by tho application . of manures cohrgaining the'' in'grcdients in which it is deficient^ and which are necessary to the successful duction of- the crop that it is intended to grow.'>£ Of course it'is ®nlyin some (cases that such a mode t of can be > giyen , effect fy f pr many!soila are so deficient in some 'of tlie^ properties of coudplete.' soils that if .would never; pay to supply these by;a'rtificiaP means 1 : But thoiigh ' itf will* not- j)ay'td' : oarry^ ' these plans into effect on a ; large" sdale, m'ucn^ may be done in obtaining good fields from whati were once poor soils, by a continued course of skilful cultivation. ■ Every farmer, has some, ,of the most important materials at hand in tho; shape of farm-yatd manure. This alone, if applied judiciously, with a propor system of tillage and rotation, vill of itself work won-^ ders.- ■ ' '.'?'*■ 3d i As yet, in tho Colonies the farmers, as a~ rule, do not resort to 'tho artificial and expensive manures as a meais of restoring the soil. There can, however, bo very little 'doubt th'atP they will be in a few years be successfully- used; s Indeed, on senne farms, where these manures",? such as bone-bust and guano, are now iised,i tho profits .accruing from the increased yiolds^ ftro fovmd to be such as to pay handsomely for,' fill the oxtra labour and expense incidental to their use. A great drawback to the introduction of those manures is the fact that very few. ■farmers here know exactly what their land is deficient in, while there w also such a varietyof soil in the province that tho treatment found l nectEsary for tho bnd :u ono place would be' quite the reverse of that required for the land

in another portion perhaps only a few miles further north or south. The establishment of an agricultural college would, no doubt, be a great boon in this respect. As most readers of this journal are aware, there is at the present time a movement on foot for the establishment of such an institution. The movement is to a great extent due to the labours of a gentleman who for some time past has been one of the leading contributors to these columns. It is to be hoped that the efforts of this gentleman and the few others who take a warm interest in agricultural matters will be productive of the desired result. Ofcago, as every one knows, offers special facilities for the formation of such a school of agriculture, and it is only a wonder that the matter has not been taken up more enthusiastically before now. It would take a long time to point out all the advantages that would accrue from an institution of this kind, and even if wo had space, \it would be rather out of place to discuss the matter in an article of this description. It may, however, furnish material for a few remarks- at some future time. For the present we will be content to leave the matter in the hands of those who have gone to so much trouble in endeavouring to change it from a possibility to a reality, and we need hardly assure our readers that it could scarcely be in better hands.