1296 ENCYCLOPAEDIA OF AGRICULTURE. suitmm.nt. 



formed in a proper manner, without occupying to.i mm I, tun,- ,• and the climate must permit of the plants 

 arriving at perfection 



S069 9. In order that soil may be advantageously subjected to continued cropping, the farmer must 

 keep up its essential qualities by ploughing, harrowing, and any other operations n, . essary to pulverize 



it. 



WTO. — 10. Soil intended for continual cultivation must have its supply of organic matter, and part also 

 of its mineral ingredients, renewed by returning to it, from time to time, in the shape of manure, what 

 hat been removed from it in the form of crops. 



8071 — II. The condition, ns well as the composition, of the manure, must Ik- attended to. because soil 

 must hare its activity preserved by adding to it, at certain periods, substances m a state of fer m entation, 

 '■ Numerous facts tend to proi i of many crops depends upon the existence of fermi ntlng 



matter in the soli, and that however rich it may be in other respects, these crops can only be advantageously 

 cultivated a ter ;i fresh additii n of manure; this is particularly the case with the turnip. Wi bout dung the 

 richest soil will bear but an Indifferent crop ; while with manure, very poor soil, if it he not too wet, will 

 at all times give a good return. Science has not as yet been able to account for this satisfactorily, although 

 many of her votaries are h illing to acknowledge its truth, ami it is obvious that an acquaintance with tne 

 fact musl be of the greatest value in assisting the farmer in his arrangements, for he will of course apply 

 dung when he intends to r.ii^c a crop requiring the existence of fermenting matter, and thus insure 

 its mi- <•, 58, « bile he does no injury to the loll iwing crops, whose growth is, to a certain extent, less de- 

 pendent on the condition of the soil." 



8072 — 12. To correct any natural faults which the soil may possess, it must be subjected to various pro- 

 cesses which hare been proved hy experience to cure the faults in question. " The chief of these are 

 draining, liming, and burning." 



8073. Draining. The importance of draining, and especially of furrow draining, is now very gene- 

 rally understood, and the practice is so widely extended that it is in some danger of causing the adv. image 

 of deep draining to be overlooked. " A soil which is naturally capable of easily getting quit of Burfai ' - 

 water, may be rendered quite marshy by the existence of a spring. Now. to furrow-drain a field of this 

 kind would, in many cases, be absurd, for in all probability the spring would be missed, and after all the 



expen f laying the drains, the soil would remain almost as wet as at the lirst. The proper treatment, 



in such a case, is to search for the rise of the spring in the highest part of the field, and having found it, 

 one good drain will frequently have the effect of drying the whole field. Again, when the wetness arises 

 from both causes conjointly, viz., spring and surface-water, it is obvious, that however free an exit be 

 given to the spring, the soil cannot be made dry without having recourse to furrow-draining to a greater 

 or less extent, according to the stillness or porosity of the soil and subsoil." • 



8074. Liming. " Lime has three distinct great effects, in addition to several minor ones : 1st. it greatly 

 hastens the decomposition of the organic matter in the soil, and in doing so renders it much more valuable 

 to the crops. 2d. It alters the texture of the soil to a certain extent, proportioned to the quantity applied. 

 3d. It adds, of course, calcareous matter to the soil. From these considerations, it follows that lime is 

 applicable to all cases where there is an accumulation of undecomposcd vegetable matter, as in poor old 

 pasture, heath, peat, inoss, moorland, and the like." Lime is not required in soils which are poor for 

 want of organic matter, nor in such as abound in chalk. Limedoes not add directly to the fertility of the 

 soil, but only increases it, by calling into activity organic matter. Lime exhausts the soil bv bringing 

 the organic matter which it contains into action ; and hence many lands will yield for a year or two alter 

 liming heavier crops than they did before, but afterwards their productive powers fall as much below the 

 natural standard, as they had been artificially raised above it by liming. 



8075. Burning. " The immediate effects of this process are fourfold. 1st. It destrovs a large quantity 

 of organic matter. 2d, It alters entirely the texture of the portion to which the heat is directly applied. 

 3d, It reduces to a caustic state the alkalies and alkaline earths contained in the burnt portion. " And 4tb, 

 By means of these alkalies it acts upon the remaining organic matter of the soil exactly as lime does, 

 'l'o arrive at a just conclusion as to the true economical merits of this process, we must bear all these 

 four facts in mind : 1st. As it destroys a large quantity of organic matter, it of course exhausts the soil to 

 the extent of the quantity destroyed ; this is, therefore, in one respect, a disadvantage. 2(1, As it com- 

 pletely alters the texture of the portion burnt, viz., by giving to the clay the feeling and texture of sand, 

 we must consider how far this would be advantageous to the soil. 3d. and 4th, As it produces alkali which 

 acts upon the remaining organic matter .if the soil, and thus further detracts from its suppli •<( organic 

 matter, it becomes of importance to decide whether the soil will bear the deterioration without a real loss 

 of value." 



mi f J — 1 1 The Effects of Vegetation upon Soil. Science explains, more or less satisfactorily, the 

 causes of the following facts. 



8077 — 1. Uncultivated soil, however rich, becomes gradually less and less fertile until it has attained the 

 condition cither of moor or marsh. 



8078—2. Uncultivated soil retains its luxuriance for the greatest length of time, when covered with forest 

 trees unit other large vegetables. 



8079 — 3. Land not disturbed hy the plough produces successive crops of different kinds, or, in other words, 

 a sort oj natural rotation is, to a certain extent, maintained. 



8080 — 4. On cultivated land, when any species of plant disappears, its place is supplied by one of less 

 value as an article of food, and thus the richest pasture comes in time to produce only the coarsest and 

 most worthless species of grass. 



"'^l.-i. Although the natural produce if uncultivated soil thus uniformly decreases in value, the soil 

 itself becomes progressively richer ; so that alien brought under the plough, it will yield much larger re- 

 turns than could be expected from its spontaneous produce. 



81182. — G. Soil continually ploughed, yields its nourishment in much greater abundance, and with greater 

 ease to plants growing upon its surface. 



s s 1 — 7. The facility with which the productive powers of well cultivated land are diminished depends 

 on its organised matter being more easily converted into compounds soluble in air and water. 



B 84— B. The decrease Offertility in carelessly cultivated soil depends, in addition to Hi above circum- 

 stance, upon a diminution in the proportion qj its impalpable matter. 



R085 — 9. Cultivated land, when properly taken cure of becomes gradually richer and richer, notwith- 

 standing the increased quantity oj produce annually removed J com it. 



8086. — in. If the same /da at be cultivated for s. v ral years successively upon the same spot, the soil much 

 rapidly decreases infertility than irhen a vac elu is kepi up. 



8087 11. Some oj the most valuable mineral constituents ol soil decrease in greater rapidity in propor- 

 tion to the greater rare bestowed upon its cultivation, altogether independent of the portions i emovedby the 

 crops. " The inure you pull erise a -oil, the more alkali will be annually remoi ed bv the rain-water." 



8088 —111. Tin: ART or CULTCBK, or the means necessary for keeping up the fertility of the soil, re- 

 quires — 



8089 —1. Manure added in proportion to the weight of the crops removed. 

 >'! 2. .1 judicious rotation of crops. 



B09] —3. Fallowing, at least in some soil'. 

 ! —A. Resting, by laying down in pasture. 



- 93. I. Manure must be added in proportion to the weight of crop removed. " It is believed that 

 careful examination will prove that there exists between the crop and the active organic matter in the 

 soil, a proportion so constant and definite, that to keep up the fertility of the soil, we must keep up this 



