Most rotations will include corn. In the northern part, the following rotations are most satisfactory: Corn, small grain, clover-2 to 4 years; corn, small grain, clover, corn, soybeans-5 years; corn, grass-legume-2 to 4 years.

A 2-year rotation of corn and soybeans for grain probably is as good as any for the less well-drained soils on level topography. A 1-year rotation of small grain and soybeans is widely used in Virginia. Rotations that include sod should be extended on soils that are susceptible to erosion or if forage and hay requirements for livestock are high.

Tomatoes fit very well into a rotation of small grain and sod as an alternate crop for corn. Other vegetables, such as sweet corn, can be added to such a rotation of 3 to 4 years with 1 year of sod.

Experiments in New Jersey and other States have shown that the total yield of crops for 3 years following a year of sod exceeds that for 4 years of continuous cultivation.

Winter cover crops of crimson clover, small grain, or ryegrass should follow all summer vegetables that are not to be followed by sod.

Potatoes do not fit into rotations with most other crops because soils for potatoes must be held at approximately pH 5.0 to control scab. Potatoes alternated with soybeans in a 2-year rotation with winter cover crop following the potatoes or a rotation of potatoes and small grain over 2 or 3 years are probably the best rotations for potatoes.

In some vegetable soils, the main objective of certain rotations is to reduce the amount of tillage. Soil compaction from traffic is a major problem in some areas of extensive vegetable farming. The best way to overcome it is to rest the land with sod and reduce the cultivation by using chemical weedkillers. The number of cultivations might be cut from four or five to two. One or two cultivations seem to be essential to achieve adequate infiltration of water and aeration of the soil.

We have little evidence to indicate that the moldboard plow should be replaced as the basic tillage instrument here. The plow gives the only satisfactory seedbed preparation for most crops of the region. For certain vegetable crops, where the crop residue is small, however, disk harrowing gives sufficient land preparation.

A different type of seedbed preparation is sometimes used for corn and soybeans in the wet soils of North Carolina and southern Virginia. Instead of flat plowing with a moldboard plow, the land is broken with linters ("middle busters") so that the rows are planted on top of ridges. That does not improve the overall drainage, but it does enable one to work the soil earlier in the spring. Many farmers on these wet soils plow and cultivate in narrow strips (150 to 200 feet wide) between lateral drains in such a way as to make the high point of the land midway between the laterals. The land slopes gently toward each lateral. Cross furrows made diagonally across rows after planting and each cultivation aid in removing surface water.

Deep tillage, with or without deep placement of lime and fertilizer, is but little used and is of doubtful value in this region.

Erosion from water and wind is slight to moderate here. Wind erosion is more prevalent on the cultivated very sandy soils and coastal beaches. Very steep land near streams in the inner Coastal Plain is almost all under permanent tree cover. Sloping land used for cultivation can usually be protected by contour planting with strip-cropping to break the very long slopes.

Although the Middle Atlantic Coastal Plain has an average of about 40 inches of rain a year, supplemental irrigation is proving to be a profitable Practice on many farms. Periods of 2 weeks with less than 0.2 inch of rain occur about once a year. Periods of 2 to 3 weeks with that amount of rain occur about once every 2 years. Such dry spells during a critical growth period may severely reduce yields.

Yields of vegetables and potatoes grown in a 3-year rotation with 1 year of sod without irrigation equaled the yields from continuous cultivation of these crops with irrigation in dry years. Irrigation increased the yield of the continuously cultivated crops by nearly 100 percent. Any practice that will reduce runoff and erosion and increase the rate of water infiltration into the soil will increase the supply of available water for the crop. It appears, then, that only the crops of higher value can be profitably irrigated. These include vegetables, potatoes, and tobacco.

The agricultural potential of the region is at least three times the 1950 production. The total area of the region is approximately 26 million acres. Of this, 55 percent was in farms and only about 50 percent of the farmland was in cropland and pasture in 1954. Thus, only 27 percent-7,150,000 acres was used for crops and pasture.

Another 25 percent of the acreage of the region could be cleared and drained for agricultural purposes. The expense of bringing those acres into production was not economically justified in 1957 at a time of agricultural surpluses of many crops in this country.

Agriculture will meet serious competition for irrigation water in this region from industrial and urban interests before the end of this century. Efficient soil management, including rotations with sod and cover crops, can reduce the drought damage to crops by improving the permeability and the available moisture-holding capacity of soils and increasing the rooting depth of crops.

One of the more urgent needs is zoning to preserve the agricultural potential of the region. We think rural zoning control should be extended. Many thousands of acres of productive farmlands have been lost to highways, airports, industrial sites, and residential areas because people have not considered the future of soil, farming, and living.