fe PRACTICE OF AGRICULTURE. Part III. 



rally acknowledged. It is the same with what are called green crops ; beans and pease, 

 potatoes, turnips, and, in an especial manner, red clover, become all of them much less 

 productive, and much more liable to disease, when they come into the course, upon 

 the same land, every second, third, or fourth year. But what the interval ought to be 

 has not yet been determined, and probably cannot (from the great number of years that 

 experiments must be continued to give any certain result) be determined, until the 

 component parts of soils, and particularly the sort of vegetable nourishment which each 

 species of plant extracts from the soil, have been more fully investigated. 



4556. A change of the variety, as well as of the species, and even of the plants of the 

 game variety, is found to be attended with advantage j and in the latter case, or a 

 change of seed, the species and variety being the same, the practice is almost universal. 

 It is well known, that of two parcels of wheat, for instance, as much alike in quality 

 as possible, the one, which had grown on a soil differing much from that on which it is 

 to be sown, will yield a better produce than the other that grew in the same, or a similar 

 soil and climate. The farmers of Scotland, accordingly, find that wheat from the south, 

 even though it be not, as it usually is, better than their own, is a very advantageous change ; 

 and oats and other grain, brought from a clayey to a sandy soil, other things being equal, 

 are more productive than such as have grown on sandy soil. {Supp. Encyc. Brit. art. 

 Agr. 144.) 



4557. The following are examples of rotations suited to different soils, as given in Brown's 

 excellent Treatise on Rural Avoirs. The basis of every rotation, he says, " we hold to 

 be either a bare summer fallow, or a fallow on which drilled turnips arc cultivated, and 

 its conclusion to be with the crops taken in the year preceding a return of fallow or drilled 

 turnips, when of course a new rotation commences. 



4558. Rotation for strong deep lands. According to this rotation, wheat and drilled 

 beans are the crops to be cultivated, though clover and rye-grass may be taken for one 

 year in place of beans, should such a variety be viewed as more eligible. The rotation 

 begins with summer fallow, because it is only on strong deep lands that it can be profit- 

 ably practised ; and it may go on for any length of time, or so long as the land can be 

 kept clean, though it ought to stop the moment that the land gets into a contrary con- 

 dition. A considerable quantity of manure is required to go on successfully ; perhaps 

 dung should be given to each bean crop ; and if this crop is drilled, and attentively 

 horse-hoed, the rotation may turn out to be one of the most profitable that can be 

 exercised. 



4559. Rotation for loams and clays. Where it may not be advisable to carry the first 

 rotation into execution, a different one can be practised ; according to which labor will 

 be more divided, and the usual grains more generally cultivated ; as, for instance, 



1. Fallow, with dung. 4. Barley. 7. Beans drilled and horse-hoed. 



2. Wheat. 5. Clover and rye-grass. 8. Wheat. 



3. Beans, drilled and horse-hoed. 6. Oats or wheat. 



This rotation is excellently calculated to insure an abundant return through the whole of 

 it, provided dung is administered upon the clover stubble. Without this supply, the 

 rotation would be cripplied, and inferior crops of course produced in the concluding 

 years. 



4560. Rotation for clays and loams of an inferior description. This rotation is calcu- 

 lated for soils of an inferior description to those already treated of. 



1. Fallow, with dung. 3. Clover and rye-grass. 5. Beans, drilled and horse-hoed. 



2. Wheat. 4. Oats. 6. Wheat. 



According to this rotation, the rules of good husbandry are studiously practised, while the 

 sequence is obviously calculated to keep the land in good order, and in such a condition 

 as to ensure crops of the greatest value. If manure is bestowed, either upon the clover- 

 stubble, or before the beans are sown, the rotation is one of the best that can be devised 

 for the soils mentioned. 



4561. Rotation for thin clays. On thin clays, gentle husbandry is indispensably ne- 

 cessary, otherwise the soil may be exhausted, and the produce unequal to the expense of 

 cultivation. Soils of this description will not improve much while under grass ; but, 

 unless an additional stock of manure can be procured, there is a necessity of refreshing 

 them in that way, even though the produce should, in the mean time, be comparatively 

 of small value. The following rotation is not an improper one. 



1. Fallow, with dung. 3. Grass pastured, but not too 5. Grass. 



2. Wheat. early eaten, 6. Oats. 



4. Grass. 



This rotation may be shortened or lengthened, according to circumstances, but should 

 never extend further in point of ploughing, than when dung can be given to the fallow- 

 break. Iliis is the keyston* of the whole ; and if it is neglected, the rotation is rendered 



