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The vast surface of the Lampasas Cut Plain is scored by the drainways arising near the western border into many valleys, which are cut below the old level of the plain into older and older belts of strata. These valleys within the area are bordered by escarpments like those found along. its western margin. The wide slopes of these valley escarpments descend in series of benches based upon various formations underlying the cap rock of the cut plain, each of which produces a soil and vegetation characteristic of a peculiar type of country. (See fig. 5.) These intaglioed belts will now be described in descending series.

-The first of the types of country resulting from the dissection of the cap rock of the Lampasas Cut Plain has been named the Walnut Prairie, after its typical development in the vicinity of Walnut, Bosque County. This has a shallow, black soil with a yellow-clay foundation, which is the outcrop of the Walnut formation elsewhere described. This formation occurs immediately below the Edwards limestone south of the Leon, and above the Paluxy sands north of that stream.

The Walnut Prairie usually occurs as benches, forming a shoulder immediately below the scarp rock of the summits of the Lampasas Plain, or as the surface of uplands, from which the summit rock has been eroded. The latter type of country is exceptional, but forms extensive areas of upland prairie, notably in Hamilton County. Toward the east this prairie occurs as belts along the stream valleys, between the remnantal mesa divides of the plain.

The Walnut Prairie first appears in Parker County, and is met with in the valleys of all the streams south to the Colorado in Hood, Bosque, Coryell, Lampasas, Bell, and Williamson counties, where it makes large areas of fertile land. The details of the occurrence of this prairie are more fully explained in the description of the Walnut formation, with the outcrop of which it is coincident. At and south of the Colorado the Walnut Prairie diminishes in significance.

-The Western Cross Timbers are a narrow forest belt or belts which attend the interior margin of the Grand Prairie, being established upon outcrops of formations below the cap rock of the Lampasas Cut Plain. Like the Eastern Cross Timbers, these consists of an upland forest growth of post oak and black-jack growing on sandy soils. These sandy soils are often so deep that wheels sink far into them and make wagon transportation very laborious. There is sufficient clay in the sand, occurring as occasional layers, to make it of considerable agricultural value. These forests and soils, as more fully shown in the geologic discussion, follow the outcrop of unconsolidated sandy strata lying at and near the