362 A NATIONAL PLAN FOE AMERICAN FORESTRY 



the vegetation can stop it. On steep slopes such erosion often con- 

 tinues unchecked by any possible vegetational control. 



In the eastern portion of the region and more particularly in the 

 Trinity, Sabine, and Neches watersheds, cultivation has led to equally 

 severe erosion. Extensive surveys by the Southern Forest Experi- 

 ment Station indicate that erosion in these drainages is largely con- 

 fined to areas in cultivation or to those worn out and abandoned. 

 The data indicate that a million acres of such land is badly eroded, 

 about one fourth of it in the black waxy belt and " cross- timbers " 

 region, and three fourths within the upper coastal plain. In the 

 upper coastal plain nearly 2 million acres of formerly arable land is 

 now lying idle, and of this about 250,000 acres is barren and actively 

 eroding. 



The above estimates are undoubtedly very conservative since they 

 take no account of sheet erosion on many of the cultivated fields. 

 Experimental data obtained by the Bureau of Chemistry and Soils, 

 the Texas Experiment Station, and other agencies have demonstrated 

 that in the agricultural sections of Texas soil losses from very gentle 

 slopes are enormous. Bennett 338 states that at the Spur substation 

 of the Texas Agricultural Experiment Station, in west Texas, 40.7 tons 

 per acre of soil was removed from a 2 percent slope of fallow land by a 

 total rainfall of approximately 27 inches. Gullying is by no means 

 as rapid on these drainages as on similar land in the silt loam uplands 

 of the lower Mississippi Basin. As a rule, gullies more than a few feet 

 in depth are not common. 



FORESTS OF THE WEST GULF DRAINAGES 

 CHARACTER AND EXTENT 



The forest area of the west Gulf drainages is estimated as 36,736,000 

 acres, or about 30 percent of the gross area of the basin. Less than 

 half of this consists of true forest, the remainder includes sparsely 

 stocked areas of scrub oak, juniper, mesquite, and chaparral which 

 predominate throughout the zone of meager tree growth in central 

 and western Texas. The areas of commercial forest, made up of two 

 major types the longleaf pine and the shortleaf-loblolly hardwoods 

 occur entirely in the eastern part of the basin and are limited mostly 

 to the upper coastal plain portion of the Sabine, Neches, and Trinity 

 watersheds. 



The long leaf pine forests, restricted almost entirely to the lower part 

 of the Sabine drainage, have been so heavily cut over as to be prac- 

 tically denuded and to be restocking only very slowly if at all. Were 

 this condition to exist in a region of steep slopes, at the head of im- 

 portant streams, the situation would be disastrous. Here, however, 

 although run-off is probably greatly encouraged, the relatively level 

 topography and the abundance of protective ground cover serve to 

 hold the soil. The soils of the long leaf land are too low in fertility 

 to be extensively cleared for agriculture. The National Forest 

 Reservation Commission has approved the purchase of 24,575 acres of 

 cut-over long leaf land in west central Louisiana, of which 17,965 

 acres have already been acquired. 



The remainder of the commercial forest consists largely of upland 

 stands made up of shortleaf or loblolly pines, or both, in mixture 



" Bennett, H. H., and Chapline, W. R. Soil Erosion a National Menace. U.S.Dept.Agr.Circ. 33, 1928, 



