Land which has lain for a considerable time in grass, is, in every situation, brought with difficulty into a pro per arable state ; because the roots of the natural grasses retain such a hold of the soil, that artificial plants cannot either thrive or prove productive, till the former are completely eradicated or destroyed. This difficulty prevails in different degrees, according to the nature of the soil cultivated ; for, upon soils of a light or mellow nature, grass roots may be destroyed with greater facili ty, and corn crops gained for a series of years at much less expense than is practicable upon soils that are com posed of clay, or incumbent upon a retentive bottom. But, though corn crops may, in the lirst instance, be easier cultivated upon sonic soils titan upon others ; yet no soil whatever can be successfully restored to grass in a suitable manner, without being previously completely summer followed, or sufficiently cleaned by a fallow crop, according to its nature, and other circumstances. It is from neglecting these radical operations, that the con version of grass land to tillage so often proves injurious both to proprietors and occupiers. The gencial rich ness of such lands, holds out a strong temptation to per sist in ploughing till the soil is completely possessed by root weeds. In this state it is not one year of summer fallow which will clean it effectually, and, of course, even when that radical operation is administered, it too often proves defective. What is worse, in many cases the disposition of the soil to produce the natural grasses, sometimes influences the possessors to continue the an cient practice of allowing it to seed itself; and, in others, to Bubb it with a thick covering of what is called hay seeds, which are seldom calculated to stock the ground with plants for returning a suitable produce. The good husbandman will not, however, follow any of these plans. He will fallow or clean the ground broke up front old grass as early as possible, and the proper time is gene rally in the second year immediately after a crop of corn has been taken. By taking one corn crop, which serves to rot the surface grasses, and fallowing- in the second year, when these grasses are in a weak and debilitated state, he can with ease put the ground in a husbandman like condition; and, by fallowing a second time after four or six crops of grain have been taken, the ground will be brought into the most appropriate condition for being seeded with grasses, and of producing double the quantity of food for cattle or sheep as could be procured from it previous to its renovation by tillage.
In order that our sentiments on these important mat ters may be perfectly comprehended, we arc under the necessity of entering at some length upon the several processes requisite from breaking up the ground in the first instance, till it is again restored to grass, and also of speaking upon these processes as applicable to diffe rent soils ; for what is good management upon one variety of soil, may deserve a different character when applied to another. It is in such matters that theorists chiefly act erroneously ; for, like the physician in the play, these gentlemen too often bleed the westward, and jalap the eastward, indiscriminately, without investiga ting the situation of the patient, or ascertaining whether these remedies ought to be administered.
We shall first treat of clay soils, because this variety prevails to a greater extent in Britain than any other ; and with them may be included all these soils incumbent upon a retentive bottom, and which of course may be considered as too wet for allowing turnip husbandry to be exercised with advantage.
Every variety of clay is difficult to cultivate, though, in favourable seasons, under the management of an expert cultivator, some of them are more productive than the richest free soil. The grain produced upon
clay land is generally of good quality, and wheat may be raised to a greater extent than is practicable upon light lands. The management, however, of clays is always expensive, and, in particular wars, ( rr,;n. are exposed to much hazard and danger. Hence, less Jew can be paid hem, them in proportion to the gl'0`,S of produce, titan !rum bens of a less expensive and ha zardous nature.
No kind of soil requires to be oftener renovated by the plough than clay, especially if it he 01 a thin nature. The hest grass is always obtained in the first year oiler being sown down, while the roots are creeping- upon the surface, and not obstructed by the poverty or steri lity of the sub-soil. Rich (lays will progressively firth prove while kept in grass, though in au inferior to those soils of a drier and less obstinate nature. Ilene c, the great propriety of exercising alternate husbandry upon clay soils ; iu other words, breaking them fre quently up with the plough, and restoring them again to grass, after being cropped for five or six years.
When grass land of a clay soil is converted to tillage, the first crop, in every case, ought to be oats ; there being no other grain that forages so well, and conse quently makes a greater return of produce at the outs,-t, when the surface is obstinate, and the natural gia,ses um subdued. To procure a lull crop, both good plough ing and plentiful harrowing are necessary. The plough should go deep, lay the furrow well over, and at same time leave it with a strong shoulder, so that the harrow may have a face to work upon. In harrowing, the horses ought to be driven lengthw ise, till the surface is in sonic measure broken, when cross harrowing may be resorted to. We have frequently seen old grass land that required eight or nine double lines of harrows be fore it could be considered as in any thing like a finished state ; but this seldom happens, unless in seasons when little frost is obtained, or where the surface is strongly bound with grass roots, and other rubbish.
The most advantageous practice is to summer fallow all such lands in the second year, and this practice is decisively recommended as being most conducive to the interest of the tenant, and the future management of the ground. Repeated trials confirm the sentiments formed on this point, and we are fully satisfied, that heavy land cannot be brought into a right cultivable state, or corn crops successfully raised, unless this radi cal measure is resorted to. Besides, the grub-worm is often a dangerous foe to corn crops on clay soils newly broken up from grass, especially in the second and third ) ear, and indeed during every subsequent year till the land is followed ; and we know no other method of ex tirpating this mischievous insect, but repeatedly plough ing the ground in the summer months, or paring and burning the surface. Another circumstance which ren ders an early fellow highly necessary, is the quantity of thistles and other rubbish usually infesting grass land, which, if allowed to remain undestroved, will effectually prevent artificial crops from thriving. It may only be added, that the fallow should be executed in the most perfect style; perhaps seven or eight furrows may lie required, with rolling, harrow ing, and hand-picking, till the soil is sufficiently cleaned and pulverized. A dressing with lime will also be highly advantageous, as all old grass land, when first ploughed, is eminently benefited by calcareous matter. Dung will rarely be required in the first instance, the quantity of animal and vegetable substances accumulated in former years, being sufficient for carrying on the growth of plants for a considerable time.