The soil of the Cecil loam consists of from 8 to 12 inches of a brown or yellow loam. The subsoil consists of a heavy yellow or red loam, or occasionally clay loam. The soil and subsoil are usually free from stones, but occasional areas have from 5 to 30 per cent of angular quartz or schist fragments on the surface. Often a mica-schist enters into the composition of the subsoil, giving it a soft and greasy feel.
The greater part of the intermediate valley or baselevel plain of the Catoctin Belt consists of the Cecil loam, and it occurs here as one large, connected area, inside of which are small areas of Cecil clay, Loudoun sandy loam, and Iredell clay loam. A considerable portion of the Catoctin Mountain also consists of the Cecil loam. In extent this is the most important soil type in Loudoun, covering about 33 per cent of the total area.
The Cecil loam, owing to its rolling character, is well drained throughout. Many small streams traverse it, affording ample outlets for surface water. The gently rolling areas are not generally subject to excessive erosion, but the steeper slopes wash badly, deep gullies and ditches being formed on the hillsides. Especially subject to erosion are the areas in which the subsoil contains a relatively large proportion of mica fragments. The soil and subsoil, though quite loamy, retain enough moisture in seasons of moderate rainfall to supply all growing crops.
The Cecil loam is devoted entirely to general farming. The crops grown are corn, wheat, grass, clover, vegetables, apples, and pears. The agricultural interests are further diversified by the practice of dairying and stock raising. The land is one of the best corn soils of Loudoun, being loamy and easily cultivated throughout the growing season. The average yield per acre ranges from 40 to 60 bushels. Wheat does very well, producing from 12 to 20 bushels per acre, and more in favorable seasons. Grass and clover yield at the rate of from 1 to 2 tons of hay per acre and form good grazing during a considerable part of the year. Apples and pears are grown everywhere on the type, usually in small orchards, and good yields of these fruits are obtained. Oats were at one time grown, and can be produced at the rate of from 35 to 50 bushels per acre, but the present acreage is small, the farmers claiming that this crop rapidly reduces the productiveness of the soil.
Nearly all of the type is in cultivated crops or pasture. The original timber growth was oak, hickory, and walnut; but little of this stands now, except on occasional woodlots. The Cecil loam is a soil which with careful treatment makes a fine farming land; but carelessly managed it very quickly deteriorates.
The soil of the Cecil clay consists of a heavy loam, red or brown in color, and having an average depth of 8 inches. The subsoil generally consists of a red clay, although it is sometimes a heavy clay loam. The surface is generally free from stones, though occasional small areas have a few quartz and granite or schist fragments. In the Piedmont areas small rounded diabase fragments occur on the surface. Occasionally on steep slopes or high knobs the soil covering has been washed away, leaving the heavy red clay exposed on the surface. These areas, however, are small.
The type occurs principally in the intermediate valley of the Catoctin Belt, between the Blue Ridge and the Catoctin Mountain, and on the west slopes of the Catoctin Mountain. In the valley it occupies several small, disconnected areas scattered throughout this region, while on the west slope of the mountain it is found in one of two long, broad areas, extending in a northeast and southwest direction. Three small areas occur near the southeastern corner of the County, and the type is here closely related to the Iredell clay loam.
The most typical areas of this soil occur in the Piedmont Plateau and on the gentle slopes at the foot of the Blue Ridge in the vicinity of Bluemont.