In 1788 Marshall of England stated that a common rotation was: 1st year, wheat, bar ley or him; 2d year, oats. beans and pulse; 3d year, bare fallow. A distinct advance was made with the realization of the value of the Norfolk four-course, which was practised on light land and originally consisted of roots, bar ley, clover, wheat. The principles involved are (1), that a deep-rooted crop shall succeed a shallow-rooted one, barley being shallow rooted and clover deep-rooted; (2) that crops of the same natural order and somewhat like tendencies, as wheat and barley, both being straw-crops and more or less subject to similar enemies, shall not succeed each other; (3) that a weedy crop shall be followed by a cleaning one, as the roots after the wheat; and (4) that a leguminous crop shall have a place in each rotation. The advantages of this system were: (1) The wheat was grown after a nitrogen gathering crop: the clover stubble was readily prepared for wheat in the fall, or if stock feed was scarce it could be pastured late and spring wheat or oats grown instead. The wheat was harvested in time to permit the land being fall plowed and cleaned for the succeeding root crop. (2) The fallow crop, roots, 'received manure and intertillage, and gave an oppor tunity to clean the land and stir it deeply. It furnished work for the horses in summer in cultivating, and a bulky crop of succulent feed for stock, which with the hay furnished con siderable manure. (3) A grain-crop follows well after a root crop, and generally little or no plowing is needed. Barley is a good crop to seed with, as it occupies the land but a short time and is not so exacting on the soil moisture as oats. (4) The clover requires a firm seed bed, and if the roots were consumed on the land and shallow tillage given in fitting the land for the barley, such was secured. The barley permitted a good growth of clover which enabled it to withstand the winter. This crop supplied the hay. The disadvantages of this system are that it is too short, the land being liable to become both clover and turnip sick, and the turnips affected with aclub-root." Under these circumstances clover and turnips could be taken every eighth year, substituting beans, peas or cowpeas for the former, and pota toes, etc., for the latter. Such close cropping renders the rotation expensive, the labor bill be ing high, but the cost may be reduced by leav ing the grass and clover seeding down for two or three years, thus making a five or six years rotation, or rt may be used as the basis for a seven or eight course. This rotation is capable of adaptations as follows: (1) Grain wheat, oats, barley, rye, corn, buckwheat; (2) cleaning or fallow crop — corn, potatoes, sugar beets, mange's, tobacco, cabbages, turnips, ruta bagas, rape, cowpeas, soy beans, sorghum, etc.; (3) Grain—barley, oats, rye, wheat, corn; (4) Legume— clover, grass and clover, cow peas, soy beans; (5) Legume— grass and clover, mown once and pastured, or pastured all the year.
In the United States the rotations of crops vary considerably in different sections. Ii•many places the succession of crops is dictated rather by accident or convenience than by any well considered principles. Corn and wheat or oats formed a common two-course rotation with the early settlers, until the land failed to produce a crop of wheat when corn was grown every second year, the land going to weeds in the in terval. The °Eastern Shore rotation,' which is a two-course, consists of corn followed by oats, with a secondary crop of Magothy Bay beans. The growth of this leguminous crop, while cur tailing the yield of oats, furnishes considerable green manure for plowing in. The first system
on the best cultivated farms in Virginia was a three-course, beginning with corn, and suc ceeded by wheat in which the grass and weeds were allowed to grow and be grazed the third year. One well-known farmer in Virginia grew dover in place of the weeds the third year to furnish green manure. A later rotation was: (1) corn or oats; (2) wheat and clover sown; (3) clover grown and plowed under in August, and the land seeded to wheat for the fourth year.
An old and successful rotation recorded for New England is corn, oats and timothy and clover, the latter remaining down for three years; thus two plowings are required in five years, one for corn, and a light plowing for oats, the grass and clover seed being sown among the oats. A modern three-course ro tation for the Eastern States is potatoes, winter rye, clover. This is a modification of a well-known Middle Western rotation, pota toes, winter wheat, dover. It embraces a root crop, a cereal and a leguminous crop. It is well suited to light and medium soils and is economical in labor, but one deep plowing being required in three years, that for the potatoes, the land being prepared for the rye by discing. The potatoes are a cash crop, the rye furnishes bedding and feed for stock, and the clover fur nishes bay, and is not left down long enough to be seriously injured by•the clover-root worm. The rotation is too short for many places, and probably the land would become clover-sick. It may be converted into a four-course by growing a crop of cora after the clover, and into a five course by sowing grass with the clover and leaving them down for two years, thus corn, potatoes, rye, grass (timothy, redtop, etc. clover), mown, grass mown and grazed. In this way two-fifths of the tilled land is plowed each year, that for corn and potatoes: the land for potatoes may be plowed in fall after the rye is sown in Septembzr, thus reducing the spring work. if milch cows are kept, the corn furnishes grain and stover or may be cut for silage, the rye may be cut green for fodder or allowed to mature, and the area in potatoes might be reduced and cowpeas, soy beans, peas and barley, or some other fodder or silage crop substituted.
For a dairy farm having half the land in permanent pasture, a satisfactory four-course is (1) corn (cut for silage) ; (2) oats• the land being fall-plowed, the crop furnishing grain and bedding; (3) wheat (sown in fall, the grain being sold or consumed, the straw used for bedding) • (4) clover (sown in spring in the wheat). This rotation permits of carrying the maximum amount of livestock and having a large supply of manure, thus enabling the crop producing power of the soil to be maintained or increased. The livestock furnish constant employment and enable the farmer to make two profits, that of the grower and the manufac turer.
A common rotation in the Middle West is corn, wheat and clover. The wheat is sown in the corn with a one-horse drill before the latter is mature, the clover being sown in the wheat. Labor is a serious problem, and this system economizes it, but one plowing being required. Consult Wheeler,