GEXKKAI. SuBVEY or TEXAS WOODLANDS. 37 



prairie, live oak becomes a tree of great diameter and spread along the 

 Colorado Eivi-r and in the San Saba country. Native trees two or three 

 feet in diameter are not uncommon along the roadsides, streets of towns 

 and cities, and in private grounds throughout Central Texas. 



The presence of live oak under the varying conditions found in 

 Central Texas from the Coast to the "Red Eiver is no more remarkable 

 than its absence in the eastern counties. Although found in the western 

 extension of the Lignitic belt, it is excluded from the bottomland 

 forests as well as from the uplands throughout the main body of the 

 Lignitic belt and from the pine and coastal regions of eastern Texas. 

 It is spreading, however, from its center of most prolific growth in the 

 south-central coastal prairie and may at some remote time become a 

 feature of the southeastern prairies. 



Some of the largest live oak timber areas in the South Texas counties 

 have been cleared for cultivation. The extension of live oak to new 

 prairie areas, however, probably offsets the areas cleared. Much of this 

 prairie soil is too valuable to permit of forest growth, so that larger 

 areas will probably be cleared each year and the live oak in South Texas 

 will be properly confined to stream borders and poorly drained areas 

 not capable of cultivation. The timber although not of great com- 

 mercial importance, furnishes vast quantities of fuel and other material 

 for home use. 



RIO GRANDE PLAIN .CHAPARRAL. 



This region embraces the arid or semi-arid territory lying south of 

 the escarpment of the Edwards Plateau, between the Gulf Coast and 

 the Rio Grande Eiver. It is commonly known as the Eio Grande Plain. 

 The northern portion, however, comes well within the post oaks of the 

 western extension of the Lignitic belt and the area of live oak timber. 

 True chaparral conditions more properly extend southward from the 

 Xueces Eiver. The Eio Grande country is distinctly a forested belt, 

 more than one-half the total area being covered with some form of 

 woody growth. Some seventy to eighty species of small trees and 

 shrub? are found, none of which occur in the Atlantic type of forest, 

 and fully one-fourth of which belong to the bean family. It is a vege- 

 tation of meager foliage, furnishing little shade, and growing in open 

 stands with prickly pear. Along the streams or benches and the dry 

 arroyas, mesquite grows at its best, and scraggly trees a foot or more 

 in diameter are not uncommon. Live oak forms a fringe along many 

 streams and reaches fair proportions. The dry uplands are in general 

 about one-half covered with mesquite, white brush, prickly pear, huisache, 

 acacias, and other species of thorny, scrubby growth from three feet 

 to eight feet in height. Among those which grow to valuable size are 

 mesquite, huisache, Texas ebony, catsclaw, retama, and green barked 

 acacia, all members of the bean family. Along the lower course of 

 the Eio Grande Eiver a number of species are of considerable commer- 

 cial value and find a market among the wood using industries of Texas. 

 Among these are lignum vitae. Mexican madrona, palmetto, Mexican 



