Book VI. MANAGEMENT OF LIME AS A MANURE. 805 



the stale of their cattle towards the dung pit, which, by this contrivance, it keeps constantly supplying." 

 {Comm. B. Agr. vol. ii.) 



4964. In tlie application of farm-yard dung to land under tillage, particular attention 

 is paid to the cleanness of the soil ; and to use it at a time vi^hen, from the pulverisation 

 of the ground, it may be most intimately mixed with it. The most common time 

 of manuring with farm-yard dung is, therefore, either towards the conclusion of the 

 fallowing operations, or immediately before the sowing of fallow crops. If no dung 

 can be procured but what is made from the produce of the farm, it will seldom be 

 possible to allow more than ten or twelve tons to every acre, when the land is managed 

 under a regular course of white and green crops ; and it is thought more advantageous 

 to repeat this dose at short intervals, than to give a larger quantity at once, and at a more 

 distant period in proportion. {General Report of Scotland, vol. ii. p. 517.) Farm-yard 

 dung, it is well known, is greatly reduced in value by being exposed to the atmosphere 

 in small heaps, previously to being spread, and still more after being spread. Its rich 

 juices are exhaled by the sun, or washed away by the rains, and the residuum is com- 

 paratively worthless. This is in an especial manner the case with long fresh dung, the 

 far greater part of which consists of wet straw in an entire state. All careful farmers, 

 accordingly, spread and cover in their dung with the plough, as soon as possible after it 

 is brought on the land. 



4965. The use of fresh dung is decidedly opposite to tlie practice of the best farmers of turnip soils ; its 

 inutility, or rather injurious effects, from its opening the soil too much, is a matter of experience with 

 every one who cultivates drilled turnips on a large scale. As the whole farm-yard dung, on such land, is 

 applied to the turnip crop, it must necessarily happen that it should be laid on in different stages of putre- 

 faction ; and what is made very late in spring, often after a very slight fermentation, or none at all. The 

 experience of the effect of recent dung is accordingly very general, and the result, in almost every case, 

 is, that the growth of the young plants is slow ; that they remain long in a feeble and doubtful state ; and 

 that they seldom, in ordinary seasons, become a full crop, even though twice the quantity that is given of 

 short muck has been allowed. On the other hand, when the manure is considerably decomposed, the 

 effects are immediate, the plants rise vigorously, and soon put forth their rough leaf, after which the 

 beetle or fly does not seize on them ; and in a few weeks, the leaves become so large, that the plants pro- 

 bably draw the greatest part of their nourishment from the atmosphere. Though it were true, therefore, 

 that more nutritive matter is given out by a certain quantity of dung, applied in a recent state, and 

 allowed to decompose gradually in the soil, than if applied after undergoing fermentation and putrefac- 

 tion, the objection arising from the slowness of its operation would, in many instances, be an insuperable 

 one with farmers. But there seems reason to doubt if fresh strawy manure would ferment much in the 

 soil, after being spread out in so small a quantity as has been already mentioned ; and also if, in the 

 warm dry weather of summer, the shallow covering of earth given by the plough would not permit the 

 gaseous matters to escape to a much greater amount than if fermentation had been completed in a well- 

 built covered dunghill. 



4965. Another great objection to the use of fresh farm-yard dung is, that the seeds and roots of those 

 plants with which it commonly abounds spring up luxuriantly on the land; and this evil nothing but a 

 considerable degree of fermentation can obviate. The mass of materials consists of the straw of various 

 crops, some of the grains of which, after all the care that can be taken, will adhere to the straw ; of the 

 dung of different animals voided, as is often the case with horses fed on oats, with the grain in an entire 

 state ; and of the roots, stems, and seeds of the weeds that had grown among the straw, clover, and hay, 

 and such as had been brought to the houses and fold- yards with the turnips and other roots given to live 

 stock. 



4967. The degree of decomposition to which farm-yard dung should arrive, before it can be deemed a pro. 

 fitable manure, must depend on the texture of the soil, the nature of the plants, and the time of its 

 application. In general, clayey soils, as more tenacious of moisture, and more benefited by being ren- 

 dered incohesive and porous, may receive manure less decomposed than well pulverised turnip soils 

 require. Some plants, too, seem to thrive better with fresh dung than others, potatoes in particular ; but 

 all the small-seeded plants, such as turnips, clover, carrots, &c. which are extremely tender in the early 

 stage of their growth, require to be pushed forward into luxuriant vegetation with the least possible 

 delay, by means of short dung. 



4968. The season when manure is applied, is also a material circumstance. In spring 

 and summer, whether used for corn or green crops, the object is to produce an imme- 

 diate effect, and it should therefore be more completely decomposed than may be neces- 

 sary when laid on in autumn for a crop whose condition will be almost stationary for 

 many months. (Sup. Ency. Brit. art. j^gr. ) 



4969. The quantity of putrescent manure requisite for each acre of land during each 

 year is estimated, by Professor Coventry, at five tons per acre annually. That quantity 

 being supplied, not annually, but in quantities of twenty tons per acre every four years, 

 or twenty-five tons per acre every five years. {QMaV' Jour. Agr. vol. ii. p. 335.) 



SuBSECT. 2. Lime, and its Management as a Manure. 



4970. Li7ne is by far the most important of the fossil manures; and, indeed, it may be 

 asserted, that no soil will ever be fit for much which does not contain a proportion of 

 this earth, either naturally or by artificial application. Next to farm-yard dung, lime is 

 in most general use as a manure, though it is one of a quite different character ; and when 

 judiciously applied, and the land laid to pasture, or cultivated for white and green crops 

 alternately, with an adequate allowance of putrescent manure, its effects are much 

 more lasting, and, in many instances, still more beneficial, than those of farm-yard dung. 

 Fossil manures. Sir H. Davy observes, must produce their effect, either by becoming 

 a constituent part of the plant, or by acting upon its more essential food, so as to render 

 it more fitted for the purposes of vegetable life. It is, perhaps, in the former of these 



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