THE vSPREAD OF TIMBERED AREAS IN CEN'TRAL TEXAS 



By J. H. Foster 

 State Forester of Texas 



Lying in the south-central part of Texas is a region known as 

 the Edwards Plateau. This is a deeply eroded, limestone country form- 

 ing the southern extension of the Great Plains and terminating 

 abruptly on the south and east in an escarpment 400 to 1,000 feet in 

 elevation, known as the Balcones Escarpment. South of this escarp- 

 ment lies the Rio Grande Plain and east of it are the great agricultural 

 prairie belts of east-central Texas. Northward extending to the Red 

 River, and northwestward to the Breaks of the Plains is a vast terri- 

 tory consisting of carboniferous and red beds deposits and granitic 

 areas which may be termed the central denuded region of north- 

 central Texas. The Edwards Plateau proper consists of limestones 

 of the older cretaceous formation, faulted and uplifted during tertiary 

 time and since then eroded into hills and narrow canyons with 

 stretches of rolling prairie between. The area of greatest erosion and 

 dissection is toward the eastern and southern escarpments, the region 

 farther west gradually flattening out until it merges into the Great 

 Plains. Erosion has also played an important part in the transforma- 

 tion of the denuded region, causing steep bluffs and isolated buttes. 

 deep gorges and long, even slopes often covered with broken rock 

 strata. 



The Edwards Plateau and the surrounding regions have during 

 recent years been undergoing a remarkable transformation from grass- 

 lands and exposed rock formations to a forested condition. This 

 is the more remarkable when it is realized that the average rainfall 

 does not exceed 25 inches per year and that it is a region of little 

 humidity, intense sunlight, and rapid evaporation. Such conditions 

 are conducive to grassland vegetation. It is not fair to assume that 

 this region has hitherto been treeless, but ' throughout central Texas 

 as a whole forest growth has been confined to the more eastern slopes 

 of the Edwards Plateau and to the canyons, stream borders and 

 occasional steep blufifs and mesa tops in the regions northward. The 

 present forests consist of three principal classes : along streams and 

 canyons, on hills and bluffs, and prairie growth. 



442 



