Texas Bureau of Economic Geology Down to Earth at Tuff Canyon, Big Bend National Park, Texas

Challenging questions from visitors to Big Bend National Park made me realize that people would welcome a detailed guidebook for a specific area in the park. Suggestions from Pat W. Dickerson, Fred W. McDowell, William R. Muehlberger, Don F. Parker, Doug Smith, and John A. Wolff greatly improved early drafts. At the Bureau of Economic Geology, Jay Raney, Susie Doenges, Becky Smyth, Eddie Collins, and Kirt Kempter gave encouragement and guidance. Sue Hovorka offered suggestions in a final reading of the guidebook. Thanks to Roland Wauer (via Kitty Coley), who provided the information on birds of Tuff Canyon and gave us permission to use a photo, as well as a painting by Howard Rollin, that appeared in a book of his. Kirt and Chris Henry offered their input on critters, too. We found other critter info at http://www.nps.gov/bibe/ and http://gorp.away.com/gorp/resource/us_national_park/tx_big_b.htm. DesertUSA (http:www.desertusa.com) allowed us the use of some of their critter and plant photos, too. Because she lives in Big Bend, Betty Axley took photos of purple prickly pear cactus for us, and cover photos are by Kerza Prewitt.

Lana Dieterich thoroughly reworked my writing, always achieving greater clarity, and Susan Lloyd did the word processing. Figures were drafted by Jamie H. Coggin, David M. Stephens made my photos and slides into text figures, and Jamie also adapted the critter photos and designed the book and its handsome cover, all under the supervision of Joel L. Lardon, Graphics Manager. Last but by no means least, Rosemary Brant Barker sustained me in the field, office, and at home.