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REGION 14: THE WESTERN CROSS TIMBERS

REGIONS 14 and 15 are strips of woodland stretching across grassland, hence the term "Cross Timbers." Both occupy sandy soil, to which they are confined. Regions 14, 15, and 16 are similar to each other in that they have the same woody dominants; namely, postoak, blackjack, and in some localities, hickory. The last is wanting in many places, as is sometimes also blackjack. Occasionally both may be present, with little or no postoak. The most abundant and widespread member, however, is postoak. In fact it is spattered out, as it were, westward and southward over regions 13, 9, 6, and 7 in those scattered localities where sandy or gravelly soil, with the right admixture of subsoil clay and sand to make a good water reservoir, occurs covered by sandy top soil adapted to a high degree of absorption in time of rain and of protection against surface evaporation in time of drouth. Such a soil is the best possible conservator of moderate or scant precipitation. Postoak and blackjack are well adapted to moderate supplies of water and, hence, are found on such soils farther west than any other trees of the eastern coastal plains forest. Always they are found on sandy or gravelly soil with a reddish clay and sand sub-soil. In Taylor and Fisher counties, as outlined below (Region 15), the westernmost representatives of this type of woody vegetation are found on deep sand. In some portions the stand of timber is open, in others it is close and thickety. In locations within the region where limestone outcrops occur, liveoak is usually found. Conversely, throughout Region 18, wherever sandy or gravelly outcrops or deposits occur, postoak is always found. Along the sinuous line of contact between woodland and prairie, mottes of timber near the edge of the prairie are the rule.

Of recent years a decided invasion by Virginia cedar has produced a noticeable scattering of this evergreen through much of the oak-hickory forest. Apparently the cedar wax-wing and other small birds plant the seeds under the oaks. An undergrowth of brushy