ARABLE LAND, is that part of the land which is chiefly cultivated by means of the plough.
Land in general is divided into arable land, grass land, wood land, common pasture, and waste.
The German agriculturist Thaer has given a classification of arable soils of known quali ties, worthy of notice. It is as follows :— Below this are very poor rye lands.
In all these soils the depth is supposed the same, and the quality uniform to the depth of at least six inches ; the subsoil sound, and neither too wet nor too dry. The last column, of comparative value, is the result of several years' careful valuation of the returns, after ti,bour and seed had been deducted.
Under the article SOIL the comparative qualities of different kinds of agricultural land are noticed. We may in this place briefly illustrate the nature and qualities of arable land by tracing the history of a corn crop.
The better the soil, the less cultivation it requires to produce tolerable crops ; hence, where the land is very rich, we find in general a slovenly culture; where the ground is less productive, more labour and skill arc applied to compensate for the want of naturalfertility. The simplest cultivation is that of the spade, the hoe, and the rake—and on a small scale it is the best; but spade husbandry cannot be carried to a great extent without employing more hands than can be spared from other occupations. The plough, drawn by oxen or horses, is the chief instrument of tillage, and has been so in all ages and nations of which we have any records. Its general form, and the mode of using, are explained under PLOUGH. The main object of ploughing is to turn over the whole surface of the ground, as a prepara tion for bringing it to a finely pulverized state, and to admit the atmosphere to act upon parts before excluded from it. When grass-land or stubble is ploughed, care must be taken to bury the grass and weeds completely, and the slice cut off by the plough must be turned over entirely, which is best done by making the width of the furrow greater than the depth. When the grass and weeds are rotten, and the ;round is ploughed to pulverize it, a narrow leap furrow is best ; the earth ploughed up is Laid against the side of the preceding ridge, which forms a small furrow between the tops )f the ridges, well adapted for the seed to Lodge in and to be readily covered with the barrows. The Norfolk farmers are very careful
sot to break the pan, as they call it, in their Light lands : this pan is formed by the pressure )f the sole of the plough and the tread of the mrses, and opposes a useful bank to the too rapid filtration of the water ; it lies from five :o eight inches below the surface. If it is broken, the manure is washed down into the .ight subsoil, and the crop suffers, especially when sheep have been folded, their dung being very soluble. In such soils an artificial pan nay be formed by the laid presser, or press frill. [PREss DRILL.] The mode in which the soil is prepared nost perfectly for the reception of the seed is rest shown by following the usual operations nt Mows. After the harvest, the plough is ;et to work, and the stubble ploughed in. The vinter's frost and snow mellow it, while the nubble and weeds rot below. In spring, as ioon• as the weather permits, it is ploughed tgain, the first ridges being turned ever as they were before : this completes the decom position of the roots and weeds. It is then stirred with harrows, or other instruments, which tear up the roots that remained; and some of these, not being easily destroyed, are carefully gathered and burnt, or put in a heap to ferment and rot, a portion of quick lime being added. Another ploughing and stirring follows, at some interval, till the whole ground is mellow, pulverized, and free from weeds ; manure is put on, if required, and immediately spread and ploughed in ; the land is then prepared for the seed.
Various instruments have been invented to stir the earth and mix it, subsidiary to the ploughing, and also to loosen and sepa rate roots and weeds. These are described under Ilanaow ; they all consist of series of spikes or teeth, which are, made to break up the clods of earth. When the soil turned up by the plough is in large hard lumps, a roller, sometimes with spikes in it, is drawn over the land to break the clods, or mallets are used to break them by hand ; but this is seldom necessary except where very stiff soils have been ploughed when too wet, and the ridges have dried and been ploughed again in dry weather.