THE VEGETATION OF THE SOTOL COUNTRY 
* OF TEXAS. 
WILLIAM L. BRAY, PH. D. 
There is a very striking and interesting type of vegetation iden- 
tified with cerain physiographic features of our arid Southwest, 
which seems to be aptly characterized as to its strongest feature by 
the briefly descriptive name sotol country. The vegetation abounds 
in plants of the Cactus, Yucca and Agave type, having besides, 
many of the most characteristic desert shrubs or chaparral species. 
The most conspicuously abundant of all the species is the sotol or 
bear grass — Dasylerion texanum — whose occurrence is well shown 
in plates I to V. It is advisable to say “conspicuously abundant” 
with reference to sotol, for it has a strong competitor for the honor 
of characterizing the country in the dagger-point leafed lechuguilla 
— Agave lechuguilla which, although a less conspicuous plant in the 
vegetation landscape, must cover almost as much of the territory, 
is certainly numerically as abundant and withal a more extreme 
type of the desert plant whose sharp, dagger-point leaf armature is 
less likely to be forgotten by the experienced than the long grace- 
fully spreading grass like leaves of the sotol. 
The physiographic feature which — climatic conditions remain- 
ing approximately desert — determines the occurrence of the sotol 
formation, is a rolling or hilly or mountain slope area whose sur- 
face is covered by loose, coarser or finer, stony debris accumulated 
by the gradual disintegration of the plateau and mountain masses 
of the arid Southwest. Typical occurrences of such country would 
be the eastern foothills and mountain slopes of the continental 
axis from Southern New Mexico through Texas and far down into 
Mexico. Such areas occur also throughout the region reaching to 
the Colorado desert and the Gulf of California. In general, one 
may say that the type of vegetation under consideration is charac- 
teristic of the greater part of the Lower Sonoran Zone where the 
above named physiographic conditions prevail. 
In Texas, the main body of the sotol country is embraced in the 
rough limestone region lying between the breaks of the DeviPs 
River and the front ranges of the Cordilleras near Marathon over 
150 miles west, extending thence south westward over the region 
of the Great Bend of the Rio Grande. Northward, tongues of the 
sotol formation reach out along the divides of the drainage area of 
