Value of Rotation.—Experience has shown the benefit of variety in crops grown on land. Among the advantages of crop-rotation are the following:
1. It enables the farmer to maintain the supply of organic matter in his soil. The roots and stubble of a grain crop are insufficient for this purpose, and the introduction of a sod or cover crop is helpful.
2. It permits the use of legumes to secure cheap supplies of nitrogen.
3. Some plants feed near the surface of the ground, and the use of other plants which send roots deeper adds to the production.
4. Some crops leave the soil in bad physical condition, and the use of other crops in the rotation serves as a corrective.
5. The keeping of livestock is made more feasible and profitable, and this leads to increase in farm manures.
6. In a proper succession of crops the soil is covered with living plants nearly all the time, and thus is prevented from washing or leaching.
7. In addition to these influences upon soil fertility, crop-rotation assists in control of insect and fungous foes and of weeds; it permits such distribution of labor on the farm that the largest total production may be secured by its employment; and it saves the farmer from sole dependence upon a single crop.
Penn's Valley, Pennsylvania.