Mesa Country 



Independence Creek creates a wetland oasis 

 in an arid Texas landscape. 



By Robert H. Mohlenbrock 



The largest geographic region 

 in Texas is the Hill Country, 

 or, more formally, the Ed- 

 wards Plateau, an elevated plane the 

 size of Pennsylvania laced with 

 canyons and flat valleys. The dramatic 

 Balcones Escarpment bounds the 

 plateau to the east and south. To the 

 north, the terrain is carved by relative- 

 ly shallow canyons; to the west, the 

 plateau blends into the Chihuahuan 

 Desert. The climate in the west- 

 ern zone is decidedly arid, but 

 even in the east it is at best semi- 

 arid. Overall, the terrain is 

 rocky; surface soil usually com- 

 prises sand or clay mixed with 

 calcium carbonate or other car- 

 bonates, a combination known 

 as caliche. Some 98 percent of 

 the plateau serves as rangeland 

 for cattle, goats, and sheep. 



I )eep canyons cut into the 

 western portion, also known as Independence Creek 



the Stockton Plateau. A few perma- 

 nent streams, fed by natural springs, 

 nourish wetland flora within just a 

 few yards of such desert plants as bar- 

 rel cactus, creosote bush, and ocotillo 

 [see "Two Faces of Texas," by Robert H. 

 Mohlenbrock, October 2004]. One such 

 stream is Independence Creek, a 

 ninety-mile-long tributary to the 

 Pecos River. Along the creek, the 

 Nature Conservancy has acquired 



Mesas near Independence Creek, despite 

 being separated by canyons, rise to a 

 uniform height, revealing the underlying 

 unity of the Edwards Plateau. 



three ranches totaling about thirty- 

 seven square miles, which is now 

 called the Independence Creek Pre- 

 serve. With the permission of its 

 stewards you can visit the preserve [see 

 contact information on opposite page]. 



One-fourth of the flow in Inde- 

 pendence Creek comes from Caro- 

 line Spring, situated at the preserve 

 headquarters. The spring feeds a sev- 

 enty-five-foot-wide pool that con- 

 nects to the creek via a short, narrow 

 tributary. Limestone cliffs act as a 

 serene backdrop to picnic facilities 

 overlooking the pool. Coastal water 

 hyssop, roundleaf seedbox, spiny na- 

 iad, and two species of pondweed are 

 visible in the crystal-clear water, and 

 fronds of southern maidenhair fern 

 hang gracefully from the lime- 

 stone rocks. Downstream from 

 the pool, Independence Creek 

 flows for fifteen miles before 

 emptying into the Pecos. 



In one woods along the west 

 side of the creek is a small tree 

 with beautiful orchidlike flow- 

 ers, known as Texas plume or 

 Anachaco orchid (Bauhinia luna- 

 rioides). The genus Bauhinia is 

 almost entirely tropical: it in- 

 cludes more than 400 species, 



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NATURAL HISTORY March 2006 



