SYSTEMATIC EXPERIMENTS IN MANURING.

Clutha Leader, Volume I, Issue 43, 6 May 1875, Page 3

SYSTEMATIC EXPERIMENTS IN MANURING.

stead, ~J2ngland r^uring ,-,aJpenb*cL.d'fi mprq (guajtqriof eent^rv| .have; been of the greatestiepvice 'to agricul-c teiee,; jrMjrLaw^ Gilbert, an accomplished chemisj>VhaS; reduced; itoisoientific; aceuraGyfbyj means' •of practical = experiments, the somewJfaV wild, ; -theories ■ of; 7 Pcqf. ; ','Mebig^ -we, •Qermant iJ^arqn. : JPov^ojeT ;S| ■. yearsMessrs Lawes and Gil^erf- |jaye >l?eenf . acjßupLuMng^ojjecjrj ttje jpur|%;wie^ce^ thejfa.cts have^en-draKnbejnjg'a farm c situated at Rotnanistead, oi wlupb / ..ha^ been- solely cteyoiied.itQ.o ea^perjmental, qrQps/! raised Jbpth: ; f^it)i9ut o.an0 .and y ..withr /Baaiiure*. , igarn^a.r.d. anji; artifiq^i t Voi'( chemical manures o^Tarious^la^sJbiay^ been used so ''the valuesqf each- r oneii^ i-'A!:corresfß)nden.t of the f ; London 'FieldjLiias reoently visited' we maffe the following ndteg^The land at Eothamstfe'a^ is a deep clay

iipon chalk, mostly drained; naturally feftile^arid reteritiver The:firstsubjectio which our attention was- ;drawn was the restorative effects of a clover crop in increasing the quantity, of , nitrogen in the soil, and this, notwithstanding: the fact that a clover crop coritains about five times as much nitrogen as a .crop of barley. The experiment was conducted on a field of lime acres, which had been under crop since 1867, and in barley since 1869, different artificial manures having been used to each crop. In 1872, half the field was sown down with clover j in the following year neither the half under barley nor in clover was manured at all, and all the produce was removed. At the present time the whole field is 7 again under barley, arid, witn the exception of one acre after clover unmanured;> has been dressed with 2 ewt. of superphosphate and 2 cwt. of nitrate of soda. The results are yery ; remarkable. The barley after clover is fully eight bushels in excess of the rest of the field, and the nnmanured ' acre "is actually as !heavy,:.showirig the! extra fertility in the land arising from the clover crop. It is not known for certaipty whether this result is due to the absorption by the leaves of ammonia from/the air, or the collection by the roots from the- subsoil; or possibly there maybe some property in the crop : causing the uriion of nitrogen and hydrogen in the soil. The subject is bejng' investigated, arid we may look for more precise knowledge ere long. Mr.. Lawes considers that the effect of a clover crop is quite equal to a dressing of 21 cwt,; of nitrate of soda. It has long been known that on certain strong s6iTs]jlarger yields of corn followed a clover crop twice mown than one grazed with sheep; although in the latter .case most of the produce was returned through the sheep; It is also well known that root growth is in proportion to the development of leaves — a crop, constantly eaten down would j consequently have less root than one; allowed to grow up ; and- whether the I leaves or the roots are the active agents] in this extraordinary production of; ""nitrogen, it is equally clear that leaf! development is necessary- to insure thet maximum effect. The analysis of the; soil in this, field showedthe presence; of more nitrogen where thejclover had: grown to the depth of 18 inches from; the surface. . The barley experiments! have been in progress since 1852. The; first point that strikes us •: is the considerable and comparatively uniform: yield of the untnanured . plot. In thej case of barley >, at Rothamstead, thei average reaches 20 bushels, each bushel; weighing 52f lb, the straw yielding; llf cwt. Contrasting this with the plot manured with 14 : tons of farmyard manure, we find an increase of 28 £ bushels, the yield for the latter being 48^ bushels; weighing 54|lb, and the straw is still more increased, viz:, to 28| cwt; Certain artificials which dp not contain an ounce of carbon produce even greater results ; ; hence we have this fact established Jbeyond doabt, that barley can : . obtain all its carbon, from the atmosphere, and that so far'as this material is concerned, the application of farmyard manure is. necessary; If we burnt all oUr straw and supplied the ashes only; the result,, as far as manuring properties are concerned, would be the same. In round numbers, the value of the ashes from, a ton of straw is about 12s 6d, therefore if a farmer can sell his straw at L 3 a ton .and retnrn LI of artificial manure of the right sort, he is benefiting liimseff, and no| in^ juring the land. We are now speaking of the straw onlyj not of the animal matter incbrpdrate& with ! the- straw in foldyard manure.- Mr Lawes considers ( that an . occasional applipation of such manure is probably the cheapest method f of supplying potfash "should the latter 'Be. deficidnt, arid' fiis oWn ptactice> is to t grpy : occafsionallyi, giving them a heavy 'dressing df riianu'rei, land then- taking ariumlier.pf cprn CJcpjp&L .TJie nextpoini wortHy! of notice J|. that -after, adong'courselof farmyard; manur^ a" number of crops must be taken befot^ aHiffciar fertility 1 is Temoyed> whereas iaTtificiat 1 three cjfops 1 suffice;- to Mrig'-down the soil tfonts natural -^reld j pn^.piot dressed witj^- 14' jtogs farniy'ard manure from T852 to^.l&tl fielded Jtasit year-Mvhich was the second witKpujfc manure — 4?^ bushelsi weighing "54^1b.

Ijw Pot/to lijiSBAS-^:— i'A. Jiiew potato; disease Has made cits, appearance in Algeria within the lastttwohyears, 8n&-has totally destriyed; two-tfcirds: at bf tlfe'cropSjj and I;hreasens^fo do even $ ljir|er[: anMnt of j^jifry,; Potatoes attacked by the' pest jareriisferly* : wqpthf Jess" -for any purpose" vvfaatev'dr. - ''{No animal will eat, themy;#ndV ,)on ppenjlng' tHe: tubers, it, is foitndgthkt tijeyaare hprifeybombed in the "centfe, and filled Mt|i.^ blackish- matter ■ tHaVgives fourth a r ve?y- offensive ordo^j.. ;tf is not.;the jßo|i?yJtis infestans tn^t is fcausing c ;jthe damage, but a" very^mmjuie insee€ of Lepidoptera orjder, of; jvliifl^. the'higtppy is little knowfl. Itoiscoiaiy tliaithe larvse ,germin§tdinHhe/xo^ oJ V^rips vegetables. fiibth d|ppsits its eggs uponAEe^ciSngshofi^oif the : p,otatoe the tnoment it appears a^Dve mey ground. 'As soqn as;^he'%gs ari». hatched, the small caterpillar^ as^sl^ider' fis hosse-hair, penetrstecinto tjie sifceni, fend its w&y doVfiDifitof the tflber, , Qie^ttWior of which it eMs away. ( iThe^ graqynich workes tne mischief' ls^unf KnoWB. in Europe, a^d;jfeQeinaTne!'jiaS Been "given toLit ,o| Bryotrojiha 1 sdllanellat - „•= ■ „ .. : ,.: . r „.rcr l i