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stm, to dry off the standing water,—to dry cut the free water in the surface soil, and to drink up the water of the subsoil, which is slowly drawn from below. If no spring, or ooze, keep up the supply, and if no more rain fall, the subsoil may be dried to a considerable lepth, cracking and gaping open, in wide fissures, as the clay loses its water of absorption, and shrinks. After the surface soil has become sufficiently dry, the land may be plowed, seeds will germinate, and plants will grow. If there be not too much rain during the season, nor too little, the crop may be a fair one,—if the land be rich, a very good one. It is not impossible, nor even very uncommon, for such soils to produce largely, but they are always precarious. To the labor and expense of cultivation, which fairly earn a secure return, there is added the anxiety of chance; success is greatly dependent on the weather, and the weather may be bad. Heavy rains, after planting, may cause the seed to rot in the ground, or to germinate imperfectly; heavy rains during early growth may give an unnatural development, or a feeble character to the plants; later in the season, the want of sufficient rain may cause the crop to be parched by drought, for its roots, disliking the clammy subsoil below, will have extended within only a few inches of the surface, and are too subject to the action of the sun's heat; in harvest time, bad weather may delay the gathering until the crop is greatly injured, and fall and spring work must often be put off because of wet.
The above is no fancy sketch. Every farmer who culti vates a retentive soil will confess, that all of these incon veniences conspire, in the same season, to lessen his returns, with very damaging frequency; and nothing is more common than for him to qualify his calculations with the proviso, "if I have a good season." He prepares his groui d, plants his seed, cultivates the crop, "does his best,"— thinks he does his best, that is,—and trusts to Providence to send him good weather. Such farming is attended witk too much uncertainty,—with too much luck,—to be satisfactory; yet, so long as the soil remains in its undrained condition, the element of luck will continue to play a very important part in its cultivation, and bad luck will often play sad havoc with the year's accounts.
Land of this character is usually kept in grass, as long as it will bring paying crops, and is, not unfrequently, only available for pasture; but, both for hay and for pasture, it is still subject to the drawback of the uncertainty of the seasons, and in the best seasons it produces far less than it might if well drained.
The effect of this condition of the soil on the health of animals living on it, and on the health of persons living near it, is extremely unfavorable; the discussion of this branch of the question, however, is postponed to a later chapter.
Thus far, there have been considered only the effects of the undue moisture in the soil. The manner in which these effects are produced will be examined, in connection with the manner iif which draining overcomes them,—reducing to the lowest possible proportion, that uncertainty which always attaches to human enterprises, and which is falsely supposed to belong especially to the cultivation of the soil.
Why is it that the farmer believes, why should any one believe, in these modern days, when the advancement of science has so simplified the industrial processes of the world, and thrown its light into so many aoniers, Miat the word "mystery" is hardly to be applied to any jpcrntion of nature, save to that which depends on the il ways mysterious Principle of Life,—when the effect of any combination of physical circumstances may be foretold, with almost unerring certainty,—why should we believe that the success of farming must, after all, depend mainly on chance? That an intelligent man should submit the success of his own patient efforts to the operation of "luck;" that he should deliberately bet his capital, his toil, and his experience on having a good season, or a bad one,—this is not the least of the remaining mysteries. Some chance there must be in all things,—more in farming than in mechanics, no doubt; but it should be made to take the smallest possible place in our calculations, by a careful avoidance of every condition which may place outi crops at the mercy of that most uncertain of all things— the weather; and especially should this be the case, when the very means for lessening the element of chance in our calculations are the best means for increasing our crops, even in the most favorable weather.
Note.—(Third edition.) The investigations of the last few years have opened a new vista in the field of agricultural science. Many of our most import int theories concerning the process by which the soil prepares manure and its own constituents for the use of plants, seem about to be revolutionized. What is described with so much confidence in the foregoing pages as the method of aeration, oxidation and chemical combination by A'hicn organic manures are developed into plant food and what is said of the conditions under which the changes take place, most easily and completely, is probably entirely wrong, as a matter of theory. There is hardly a doubt that the development of plant food from refuse organic matter of all kinds is very largely, if not almost entirely, the work of minute organisms known under the geueric term "bacteria," whose office it seems to be to break down the last vestige of organic character, and to reduce organic matters to their mineral elements. The bacterium of nitrification is obviously one of the most important aids to the preparation of organic plant food.
Fortunately, the conditions under which these organisms act and produce the effects which have so long been recognized in spite of our ignorance of the precise cause, are exactly the same as to aeration, moisture, and the absence ot saturation as are above insisted Od as necessary for the processes formerly supposed to do their woik.
HOW DRAINS ACT, AND HOW THEY AFFECT THE SOIL
For reasons which will appear, in the course of this work, (he only sort of drain to which reference is here made is that which consists of a conduit of burned clay, (tile,) placed at a considerable depth in the subsoil, and enclosed in a compacted bed of the stiffest earth that can conveniently be found. Stone-drains, brush-drains, sod-drains, mole-plow tracks, and the various other devices for forming a conduit for the conveying away of the soakage-water of the land, are not without the support of such arguments as are based on the expediency of make-shifts, and are, perhaps, in rare cases advisable to be used; but, for the purposes of permanent improvement, they are neither so good nor so economical a* tile-drains. The arguments of this book have reference to the latter, (as the most perfect of all drains thus far invented,) though they will apply, in a modified degree, to all underground conduits, so long as they remain free from ob structions. Concerning stone-drains, attention may properly be called to the fact that, (contrary to the general opinion of farmers,) they are very much more expensive than tile-drains. So great is the cost of cutting the ditches to the much greater size required for stone than for tiles, of handling the stones, of placing them properly in the ditches, and of covering them, after they are laid, with a suitable bar rier to the rattling down of loose earth among them, that, as a mere question of first cost, it is far cheaper to buy tiles than to use stones, although these may lie on the sural
face of the field, and only require to be placed in the trendies. In addition to this, the great liability of stonedrains to become obstructed in a few years, and the certainty that tile-drains will, practically, last forever, aro conclusive arguments in favor of the use of the latter. If the land is stony, it must be cleared; this is a proposition by itself, but if the sole object is to make drains, the best material should be used, and this material is not stone.
A well laid tile-drain has the following essential characteristics : — 1. It has a free outlet for the discharge of all water which may run through it. 2. It has openings, at its joints, sufficient for the admission of all the water which may rise to the level of its floor. 3. Its floor is laid on a well regulated line of descent, so that its current may maintain a flow of uniform, or, at least, always sufficient rapidity, throughout its entire length.
Land which requires draining, is that which, at some time during the year, (either from an accumulation of the rains which fall upon it, from the lateral flow, or soakage, from adjoining land, from springs which open within it, or from a combination of two or all of these sources,) becomes tilled with water, that does not readily find a natural outlet, but remains until removed by evaporation. Every considerable addition to its water wells up, and soaks its very surface; and that which is added after it is already brim full, must flow off over the surface, or lie in puddles upon it. Evaporation is a slow process, and it becomes more and more slow as the level of the water recedes from the surface, and is sheltered, by the overlying earth, from the action of sun and wind. Therefore, at least during thf periods of spring and fall preparation of the land, during •be early growth of plants, and often even in midsummer, the water-table,—the top of the water of saturation,—if within a few inches of the surface, preventing the natural descent of roots, and, by reason of the small space to n