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THE southern portion of this region, below the middle of Burnet County, is characterized by the bold limestone hills which constitute the Balcones Escarpment and which support a vegetation featured by Spanish oak, scrub liveoak, shinoak and Mexican cedar. North of Burnet County broad fertile valleys lie between prominent limestone hills, the latter being covered by essentially the same vegetation as the bolder hills to the south. A noticeable correlation exists in many regions between an exposed geologic stratum and its vegetational dominants. For example, Spanish oak here characterizes the Walnut Springs limestone; an open stand of cedar, the terraces of the Glenrose; liveoak and cedar, the Edwards. Stream courses are marked throughout by the presence of pecan, bur oak, elm, hackberry, liveoak, and others. Many high sandy stream terraces are covered by mesquite, which is scant in the uplands of the region; presumably because the soil overlying the hard unweathered limestone is too thin to permit the growth of the long tap-root which is characteristic of, and apparently essential to, this plant.

Grasses are sage (including the little bluestem), grama, needle, dropseed, buffalo, running mesquite, curly mesquite, Muhlenbergia, Triodia, triple-awn, and many other less prominent ones. Johnson Grass is a common pest on cultivated ground.

Fox-glove, mints, sages, winecups and other mallows, Indian paintbrush, Roemer's Phlox, verbenas, bush honeysuckle, redbud, Mexican buckeye, Texas mountain laurel, common buckeye, plum, wild cherry, mountain daisy, and many of its relatives, firewheels, Coreopsis, Thelesperma, pink, white and yellow evening primroses, mustards, Clematis, buttercups, Anemones, carrots, squaw-weeds, dock, and a riot of other flowering herbs and shrubs produce unsurpassable richness of spring color.

In general the southern portion of this region is a sheep, goat and cattle country; the northern being divided between farming on the fertile valley land and grazing on the rougher unarable hills.