The land here is in a high state of cultivation and, according to its peculiarly varying and unalterable adaptability, produces enormous crops of all the staple grains of the County. The soil in the vicinity of Oatlands, included in this zone, is stiff and stony, except such as is adjacent to water courses, or the base of hills, where it is enriched by liberal supplies of decayed matter, which render it loamy and inexhaustible. In the main, it is of a generous quality, so pertinaciously retaining fertilizers as to withstand the washing of the heaviest rains. Still it is an anomaly that some of the richest areas in this region will not produce wheat; while, in the cultivation of rye, oats, and corn, satisfactory results are almost invariably obtained. Likewise there are but a few parcels whereon white clover does not grow spontaneously and in the greatest abundance. Than these, better pasture lands are found nowhere east of the Blue Ridge. Limestone occurs here in vast quantities. In the Valley of Loudoun, between the Catoctin and Blue Ridge mountains, the soil is formed from gneiss, clay-slate, hornblend, greenstone, and quartz. The happy combination of these materials produces a most excellent and durable soil, containing, in fair proportions, alumina, silex, potash, lime, and other fertilizing minerals. Certain fertilizers have been successfully employed in improving its natural fertility, and when it is partially exhausted by excessive tillage, rest alone will restore it. _Loudoun Sandy Loam._ The Loudoun sandy loam consists of from 8 to 12 inches of a heavy brown or gray sandy loam, underlain by a heavy yellow or red loam or clay loam. Often the subsoil contains a considerable quantity of coarse sand, making the texture much the same as that of the soil. The sand of the soil and subsoil is composed of very coarse rounded and subangular quartz particles. The surface material is not a light sandy loam, but is more like a loam containing considerable quantities of very coarse quartz fragments. It is generally quite free from stones, but small areas are occasionally covered with from 5 to 20 per cent of angular quartz fragments several inches in diameter. The Loudoun sandy loam occurs in irregular areas of considerable size in the intermediate valley between the Blue Ridge, Short Hill, and Catoctin mountains. The largest area of the type is found in the vicinity of Round Hill.