Bermuda-grass, annual lespedeza, lespedeza sericea, and crimson clover are commonly grown, but generally low yields reflect the low average rates of fertilization. On the better upland soils of the Tennessee Brown Loam area, for example, it was found that yields of lespedeza averaged only about 1 ton of hay an acre. Yields of permanent pastures also have been low.

The soils, when put to the use for which they are best suited, have good potentials for crop production, however. The first consideration is to fit the cropping system to the soil with respect to its drainage, workability, susceptibility to erosion, and moisture relations.

The hilly phase of the upland soils might well be in forest, the sloping phase in pasture or forest, the gently sloping phase in pasture, the undulating phase in close-growing crops, and the gently undulating to level phase in row crops.

A carefully planned fertilization and liming program is necessary. Studies at the Brown Loam Branch Experiment Station at Raymond, Miss., in 1949 and 1950 showed that 296 pounds of beef an acre were produced between November and May when 100 pounds of nitrogen and 60 pounds of phosphoric oxide were applied on fall-planted oats that were grazed compared to 198 pounds on the check plots. The addition of potash did not improve yields. Later studies with other winter-grazing crops indicated that such combinations as oats and crimson clover or ryegrass and crimson clover produce up to 400 pounds of beef an acre during the cool season.

A number of experiments in Mississippi in 1948-1951 showed yield responses from 36 to 145 percent by permanent pasture on typical Brown Loam soils to phosphate applications; yields were about 6 thousand pounds of dry matter. Coastal Bermuda-grass can be grown well on these soils, although there has been a lag in its use in the area. Its very high potential production makes it one of the most desirable sod grasses here.

Cotton grown on adapted land can produce excellent yields with proper fertilization, insect control, and other required practices. The average potential yield in Tennessee under commercial farming conditions has been estimated to be a bale, or slightly more, an acre; the estimate should also apply to similar soils and management levels farther south. In experiments at four locations in Mississippi in 1954, a very dry year, the average for the highest yielding treatment was a bale an acre.

In these tests, in which the recommended practices were followed, there was no response to potash and little response to phosphate, but the addition of nitrogen brought a large increase in yields.

Corn yield on the upland soils often is limited by inadequate moisture. Yields at the Mississippi Brown Loam Branch Experiment Station were limited by moisture in 1952, 1953, and 1954, when no response was found to more than 60 pounds of nitrogen an acre, although in years of good rainfall as much as 150 pounds is required for maximum yield. Good yields, estimated to average 75 bushels an acre, can be made in most years on the less droughty bottom-land soils, compared to about 45 bushels on the upland soils.

The recommended practices to control runoff are cultivation on the contour, use of sodded waterways, the judicious use of tillage to improve the infiltration rate, and the addition of Organic matter to the soil.

When hardpans occur within the upper foot of the soil profile, they can be broken by ordinary subsoiling equipment. Tests in Mississippi indicated that mechanical destruction of the hardpan would be beneficial in the years when moisture is limited but not to the extent of complete crop failure. It would also improve internal drainage and aeration in years of excessive rainfall. The decision whether to subsoil in a specific instance, however, would depend on the depth of the pan at that location, the cost, and the crops to be grown.

THE BLACK PRAIRIE AREA-or Black Belt is a relatively narrow band of heavy clay soils, about 20 miles wide, that extends from the eastern part of Alabama to the northeastern corner of Mississippi. The land is gently rolling and is well suited to the use of large machinery. The soils are sticky when wet, and large cracks form when the soils are dry.

The area, which comprises about 10 percent of the arable land in Alabama and Mississippi, is different from most of the Coastal Plain in that the soils were formed from chalk and very heavy marine clay deposits. About one-third of the area has calcareous soils, chiefly Sumter and Houston. The rest is made UP of gray to red acid clay soils, the more important of which are Vaiden, Eutaw, and Oktibbeha.

Grass was the primary native vegetation, and the area was known as the Black Prairie or canebrakes. A soil survey in 1902 of Perry County, Ala., showed that the Black Prairie soil there was Houston clay. Today most of it would be mapped as Sumter clay, which is generally considered to be an eroded phase of Houston, in which the weathered chalk appears at or near the surface.

Most of the soils were fairly well supplied with native potassium, but deficiencies of potassium have become widespread after long cropping. The virgin soils had too little phosphorus.

The Black Belt for many years was one of the leading cotton-producing sections in the Southeast. The arrival of the boll weevil about 1914 was a serious blow, however, and cotton production declined rapidly afterward. The boll weevil was more serious here than in some other areas because the heavy, poorly drained soils made it almost impossible to plant cotton early enough to reduce damage from weevils to tolerable levels.

The fact that the natural vegetation of the area was grass and clover influenced research workers, when declining incomes and abandonment of land followed the elimination of cotton as a major source of income, to consider means of stimulating the growth of pasture and forage plants and to develop a livestock program to utilize the forage.

Early studies in Alabama and elsewhere have shown that most of the soils responded well to superphosphate but poorly to potash.

The acid soils need lime for most legumes. The chalk that occurs in outcrops and on eroded hillsides may be used as a cheap source of lime. Because it may have a calcium carbonate equivalent of 50 or 6o percent, it should be used at double the rate recommended for good agricultural lime. As a rule, it may be spread at less cost than an equivalent amount of agricultural lime can be spread.

Permanent pastures are an important part of the forage program. Dallisgrass-whiteclover is the main mixture in them. Johnsongrass is used extensively as a hay and pasture crop and often is grown with vetch or Caley peas. The legumes extend the length of the grazing season and furnish nitrogen for the Johnsongrass.

Nevertheless, less than one-half of the open permanent pastureland is considered improved, and only about 25 percent of the improved pastures are fertilized regularly. The acreage of pasture that is fertilized receives an estimated average of 10 pounds of nitrogen, 70 pounds of phosphoric oxide, and 25 pounds of potash an acre annually. That means that when the total acreage of improved pasture is considered, the average application is only about 2 to 3 pounds of nitrogen, 18 pounds of phosphoric oxide, and 6 pounds of potash an acre.

Sizable acreages of small grain are grown for grazing and grain, but cotton and corn are not grown to any great extent in the Black Belt of Alabama. A considerably larger proportion of the Black Belt soils in Mississippi are in row crops than in Alabama.

Most forage and pasture crops can be grown successfully with proper fertilization, and the production of forage for conversion to meat and milk could be increased greatly. The improved pastures receive only about 25 percent of the recommended amounts of phosphate and potash. If all the open land were improved and well fertilized, the income from livestock products could be more than doubled.

Some forage plants cannot be grown on the calcareous soils here, although the climate suits them. Crimson clover and annual lespedeza become chlorotic because available iron is insufficient. Sericea has not done well in some places. Alfalfa has yielded well on the calcareous soils, but it is not recommended for the heavy acid soils. Well-fertilized alfalfa grown on limed soil at the Black Belt substation at Marion Junction, Ala., produced nearly 5 tons of hay as an average in 1948-1954.

Liberal applications of superphosphate are necessary for the establishment and maintenance of good clover-grass pastures. As in other areas long in cultivation in the Southeast, considerable phosphorus has accumulated in the older, well-fertilized pastures, and less phosphorus is now required annually for good production. Workers at the Alabama Agricultural Experiment Station discovered that 400 pounds of superphosphate annually increased the yield of beef 119 pounds an acre as an average. Average beef gains in a 3-year period were 366 pounds with superphosphate alone and 435 pounds with superphosphate plus 150 pounds of potash every 3 years.

The lime requirement of the acid soils of the Black Belt is much the same as those of other acid soils of the South. east despite their high exchange capacity and low pH value. These montmorillonitic soils have a much higher content of exchangeable calcium and a higher percentage of base saturation for a given pH level than the kaolinitic soils of the region. Thus, although some of the soils have a pH as low as 5.0, only moderate amounts of lime are needed for most crops. Even on the more acid soils, an application of 2 tons of lime an acre is usually enough for Dallisgrass-whiteclover pastures.

Some row crops are grown in the area. Branch Experiment Station at Brooksville, Miss., has shown that with power equipment and improved insecticides excellent yields of cotton and corn can be made. Yields of corn in 1949-1955 ranged from 20 bushels an acre in a year of severe drought to slightly more than 100 bushels in years of good rain.

For high yields of corn and cotton, liberal applications of the three major nutrient elements are needed. In years of normal rainfall, corn has responded well to 150 pounds of nitrogen and 60 pounds of phosphoric oxide an acre.

THE HIGHLAND RIM has soils that are derived from cherty limestone and are frequently underlain by fragipans on the more level sites.

They are acid and have low inherent fertility but are responsive to good management. They are well suited to general farming.