The Application of Manure.

Otago Witness, Issue 2209, 2 July 1896, Page 7

The Application of Manure.

. TO THE EDITOR. Sir,— ln your. issue of June 25 you publish the following statement by Dr Ojston in reply to Dr Nevill's, quVstiou as (o the advisability of manuring ground for vegetables, &c, :— '• Freeh manure was of no use : it must ripen and putrefy. If manure was well , ripenei aad fermented it wasthoroughly good." , B.fere stating,, my own experience, with numerous experiments in manuring land both with fresh and ripenei manure I will quite a few of the recognised authorities on this most important subject. Cuthbert William Johnston, in his wellknown work "On Fertilizers," says :— " There is no doubt manure cannot be appliod more advantageously than in as fresh a state as possible ; for otherwise the lois b F its most valuable constituents commences as soju a3 ever fermentation begins." Sir Humphrey Davy, a very eminent chemist, some years since, when chemistry first began bo be applied to agriculture, tried numerous experiments, which in his opinion appeared to prove "that'by allowing manure to ferment in heaps a. great portion of the ammonia and carbonic acid which it contained escapsd during this fermentation, and in order to avoid the loss of this valuable matter he recommended that manure should be applied to the ground in «s fresh a state as possible, and allow ftrmentv tion to take place in the soil." Again, in one of the g&nie author's letters on ■ .agricultural chemistry, he. says :— " The fermentation and putrefaction of manures in the free atmosphere are noxious processes ; b&neath' the surface of the ground .they are salutary operations." '"''•., Charles M'lntDsb, in his. "Book of the Qarden," says: — "The best compost heap Tb ths coil. itself, and the best system of manure management is to bury it in the soil before it loses any of its fertil'sing properties. By this means the ground becomes enriched by the ,very' essence of the manure, which would otherwise be allowed to escape in a gaseous state -during fermentation, and be deprived of much of its.best properties while undergoing unnecessary decomposition, leaving ib at last in a state little better, than that of a mass of inert peaty matter." AnoSner well-known., writer on agricultural matters says:— "The gases emitted, by the , putrefaction of a manure heap are so much lost to the vegetable matters of the so;}, and is aa injury never submitted to by the enlightened cultivator bub from* an unavoidable necessity." The late Francis Blakie, in his valuable book on the management of manures* says .— " Manure is usually' thrown out at the stable doors, and then accumulates in a large heap, which very soon ferments and heats to an excess, thereby losing from 50 to 75 per cent, of its value." Dr Madden observes :— " Notwithstanding the vast importance of, manure as a fertiliser, few things within- the whole range of rural economy are so shamefully wasted and misused. Unnecessary exposure to the weather, excessive fermentation, and .. a slovenly or ill-timed application of it to tlie soil are of everyday occurrence 1 . To avoid these the manure should be committed to the soil as soon after it is made as convenient, and the proceßS of fermentation and decomposition allowed to go on there." Experiments stated 'in Morton's " Cyclopaedia of Agriculture" show by chemical analysis that manure, loses more, than is generally imagined by the process of "making", as usually performed/ 100 cwt of fresh farm yard manure is reduced to 80owbif allowed bo lie till the straw is half rotten; 100c wb of fresh farm yard manure is reduced to 6Qowfc if allowed to ferment until

it becomes "fat and cheesy"; lOOewb of. fresh farmyard manure is reduced to 40cwt if co.-npletely decomposed. This, loss nob only affects the watsr and pother ,leis valuable constituents, of farm yar,cf';mtintjfe, but *J«o,* ita" most- fertilising ingredient— ait'rogen n ., : looawL of fresh' farmyard manure' contains about 40, b of nitrogen, and that by fermentation during .the first period 51b of nitrogen is dissipated in the form of. the volatile ammonia r in the second, 101b ; in the third, 231b. Completely decomposed manure has thus lost about one-half of its most va'uible constituent. The practical deduction which appears to be warranted by these experiments .is : Where it is possible apply farmyard manure in a fresh state to the land. Our own experience satisfies us as t) the advantage of manuring at these times and in this way. We have only to look to tlie highest cultivated ground in Brifoin (tho London market gardws) for a corroboration' of the fact. They lay on the. fresh manure as they receive ib, nob with a view so much to benefit the succeeding crop as to keep the ground in a high state of enrichment for all succeeding on 9?, the manure undergoing all tlTo while'the-'nectfsary chsnjes-fro'm a solid to a soluble state, If necessary, I could quote a dczsa more authorities to prove that all manure) should be' put iafco the soil in as fresh a state as possible, but I consider the above sufficient proof of the popular fallacy in using decomposed manure;. .For local proof ooe has only to visit any of ' the numerous Chinese gardens - around Duuedin, where he will find fresh manure being at ouca dug into the ground. If, as Dr O,<«ton asserts, "fro3h manure is of no value," will he inform we tillers of, the roil what produces the abundant crops of vegetables f u und in these gardens ?An employee of mine, who ba* hid 40 years' experience in farm and garden work in .the -north of Scotland, asserts "that ib. is. many years since the antiquated idea of rotting manure previous to application ' to the land- bad. been discarded, .all manure being at once ploughed or .dug fa ia a fresh state." I have already occupied* tso much space to detail my own observations and ex-->j>erinieutß, ,but I can assert without a shadowof doubt that manure in a decomposed state requires double the bullPto equal that of fresh manure in prod ; ioiug a succeeding crop, whether that crop be tree 3, grain, or vegetables.—l am, &0., Danedin, Juno 26. Ruia.