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“ perceive that both the pores and canals are no longer “represented white, but black, this color being used to in“dicate water; in this instance, therefore, water has taken “the place of air, or, in other words, the soil is very wet. “If we observe our seed a now, we find it abundantly “supplied with water, but no air. Here again, therefore, “germination cannot take place. If may be well to state “here that this can never occur eacactly in nature, because, “water having the power of dissolving air to a certain “extent, the seed a in Fig. 2 is, in fact, supplied with a “certain amount of this necessary substance; and, owing “to this, germination does take place, although by no “means under such advantageous circumstances as it would “were the soil in a better condition.
“We pass on now to Fig. 3. Here we find a different “state of matters. The canals are open and freely sup“plied with air, while the pores are filled with water; and, “consequently, you perceive “that, while the seed a has “quite enough of air from “the canals, it can never be “without moisture, as every “particle of soil which o “touches it is well supplied “with this necessary in- s/ “gredient. This, then, is o “the proper condition of soil to “for germination, and in Kools “fact for every period of the Fig. 3.- A DRAINED SOIL. “ plant's development; and this condition occurs when the “soil is moist, but not wet-that is to say, when it has the “color and appearance of being well watered, but when it “is still capable of being crumbled to pieces by the hands, “without any of its particles adhering together in the “familiar form of mud.”
As plants grow under the same conditions, as to soil, that are necessary for the germination of seeds, the foregoing explanation of the relation of water to the particles of the soil is perfectly applicable to the whole period of vegetable growth. The soil, to the entire depth occupied by roots, which, with most cultivated plants is, in drained land, from two to four feet, or even more, should be main tained, as nearly as possible, in the condition represented in Fig. 3,-that is, the particles of soil should hold water by attraction, (absorption,) and the spaces between the particles should be filled with air. Soils which require drainage are not in this condition. When they are not saturated with water, they are generally dried into lumps and clods, which are almost as impenetrable by roots as so many stones. The moisture which these clods contain is not available to plants, and their surfaces are liable to be dried by the too free circulation of air among the wide fissures between them. It is also worthy of incidental remark, that the cracking of heavy soils, shrinking by drought, is attended by the tearing asunder of the smaller roots which may have penetrated them.
The Injurious Effects of Standing Water in the Subsoil may be best explained in connection with the description of a soil which needs under-draining. It would be tedious, and superfluous, to attempt to detail the various geological formations and conditions which make the soil unprofitably wet, and render draining necessary. Nor-as this work is intended as a hand-book for practical use, is it deemed advisable to introduce the geological charts and sections, which are so often employed to illustrate the various sources of under-ground water; interesting as they are to students of the theories of agriculture, and important as the study is, their consideration here would consume space, which it is desired to devote only to the reasons for, and the practice of, thorough-draining.
To one writing in advocacy of improvements, of any kind, there is always a temptation to throw a tub to the popular whale, and to suggest some make-shift, by which a certain advantage may be obtained at half-price. It is proposed in this essay to resist that temptation, and to adhere to the rule that “whatever is worth doing, is worth doing well,” in the belief that this rule applies in no other department of industry with more force than in the draining of land, whether for agricultural or for sanitary improvement. Therefore, it will not be recommended that draining be ever confined to the wettest lands only; that, in the pursuance of a penny-wisdom, drains be constructed with stones, or brush, or boards; that the antiquated horse-shoe tiles be used, because they cost less money; or that it will, in any case, be economical to make only such drains as are necessary to remove the water of large springs. The doctrine herein advanced is, that, so far as draining is applied at all, it should be done in the most thorough and complete manner, and that it is better that, in commencing this improvement, a single field be really well drained, than that the whole farm be half drained.
Of course, there are some farms which suffer from too much water, which are not worth draining at present; many more which, at the present price of frontier lands, are only worth relieving of the water which stands on the surface; and not a few on which the quantity of stone to be removed suggests the propriety of making wide ditches, in which to hide them, (using the ditches, incidentally, as drains). A hand-book of draining is not needed by the ‘owners of these farms; their operations are simple, and they require no especial instruction for their performance. This work is addressed especially to those who occupy lands of sufficient value, from their proximity to market, to make it cheaper to cultivate well, than to buy more land for the sake of getting a larger return from poor cultivation. Wherever Indian corn is worth fifty cents a bushel, on the farm, it will pay to thoroughly drain every acre of land which needs draining. If, from want of capital, this cannot be done at once, it is best to first drain a portion of the farm, doing the work thoroughly well, and to apply the return from the improvement to its extension over other portions afterward. In pursuance of the foregoing declaration of principles, it is left to the sagacity of the individual operator, to decide when the full effect desired can be obtained, on particular lands, without applying the regular system of depth and distance, which has been found sufficient for the worst cases. The directions of this book will be confined to the treatment of land which demands thorough work. Such land is that which, at some time during the period of vegetation, contains stagnant water, at least in its subsoil, within the reach of the roots of ordinary crops; in which there is not a free outlet at the bottom for all the water which it receives from the heavens, from adjoining land, or from springs; and which is more or less in the condition of standing in a great, water-tight box, with openings to let water in, but with no means for its escape, except by evaporation at the surface; or, having larger inlets than outlets, and being at times “water-logged,” at least in its lower parts. The subsoil, to a great extent, consists of clay or other compact material, which is not impervious, in the sense in which india-rubber is impervious, (else it could not have become wet,) but which is sufficiently so to prevent the free escape of water. The surface soil is of a lighter or more open character, in consequence of the cultivation which it has received, or of the decayed vegetable matter and the roots which it contains. In such land the subsoil is wet-almost constantly wetand the falling rain, finding only the surface soil in a condition to receive it, soon fills this, and often more than fills it, and stands on the surface. After the rain, come wind and sun, to dry off the standing water, to dry out the free was ter 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 depth, 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 subject, almost, to the direct 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 cultivates a retentive soil will confess, that all of these inconveniences 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 ground, 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 with