 Echinocactus horizonthalonius (devil s head cactus, or horse crippler) with daggerlike spines on a small ridge near Juniper Canyon Trail south from Upper Juniper Spring. Big Bend National Park, Texas, November 22, 2007
 Camping on a small ridge near Juniper Canyon Trail south from Upper Juniper Spring. Big Bend National Park, Texas, November 22, 2007
 Lower part of Juniper Canyon Trail. Big Bend National Park, Texas, November 23, 2007
 Lower (flat) part of Juniper Canyon Trail. Big Bend National Park, Texas, November 23, 2007
 Boot Rock, view from Juniper Canyon Trail. Big Bend National Park, Texas, November 23, 2007
 Northeast Rim, view from lower part of Juniper Canyon Trail. Big Bend National Park, Texas, November 23, 2007
 Crown Mountain, view from lower part of Juniper Canyon Trail. Big Bend National Park, Texas, November 23, 2007
 Dead juniper on Devils Hall Trail in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Weathered wood on Pinnacles Trail near Juniper Flat. Big Bend National Park, Texas, November 22, 2007
 Purple-tinged prickly pear cactus on Smokey Creek Trail near Trap Spring east from Mule Ear Overlook. Big Bend National Park, Texas, November 25, 2007
 El Capitan Mountain with prickly pears cactus in foreground, view from upper Roadside Park. Guadalupe Mountains National Park, Texas, December 28, 2007
 Dry juniper on South Rim. Big Bend National Park, November 28, 2009
 Dry juniper tree on South Rim at morning. Big Bend National Park, November 29, 2009
 Purple-tinged prickly pear cactus in the middle part of Smokey Creek Trail. Big Bend National Park, Texas, November 25, 2007
 Pitaya(?) cactus on Smokey Creek Trail east from Mule Ear Spring. Big Bend National Park, Texas, November 25, 2007
 Bark of alligator juniper in McKittrick Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Santa Elena Canyon west from Smokey Creek Trail east from Mule Ear Spring. Big Bend National Park, Texas, November 25, 2007
 Alligator juniper (Juniperus deppeana) near El Capitan Trail. Guadalupe Mountains National Park, Texas, December 27, 2007
 Drooping juniper (Juniperus flaccida Var. flaccida) on Southeast Rim. Big Bend National Park, November 28, 2009
 Upper section of Boot Canyon Trail. Big Bend National Park, November 27, 2009
 Upper part of Boot Canyon Trail. Big Bend National Park, November 27, 2009
 Prickly pears near El Capitan Trail. Guadalupe Mountains National Park, Texas, December 27, 2007
 Prickly pears and yucca near El Capitan Trail. Guadalupe Mountains National Park, Texas, December 27, 2007
 Smokey Creek Trail east from Mule Ear Spring. Big Bend National Park, Texas, November 25, 2007
 Cane Cholla cactus and Southeast Rim, view from east part of Dodson Trail. Big Bend National Park, Texas, November 23, 2007
 Prickly pears cactus on East Trail in Lost Maples State Natural Area. Vanderpool, Texas, November 8, 2008
 Bee Mountain, view to the west from Smokey Creek Trail near Mule Ear Spring. Big Bend National Park, Texas, November 25, 2007
 Elephant Tusk Rock, view from Fresno Spring near Dodson Trail. Big Bend National Park, Texas, November 24, 2007
 Goat Mountain, view to the north from Smokey Creek Trail near Mule Ear Spring. Big Bend National Park, Texas, November 25, 2007
 Upper section of Hiker s Staircase near Devil s Hall in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Alligator juniper north from Capulin Canyon in Bandelier National Monument. New Mexico, near Los Alamos, May 24, 2008
 Smokey Creek Trail near Trap Spring east from Mule Ear Overlook, view to the west. Big Bend National Park, Texas, November 25, 2007
 Drying juniper twig north from Capulin Canyon in Bandelier National Monument. New Mexico, near Los Alamos, May 24, 2008
 Upper part of Boot Canyon. Big Bend National Park, November 27, 2009
 Cactus on rocks of Smokey Creek. Big Bend National Park, Texas, November 25, 2007
 Purple spineless prickly pears cactus in Davis Mountains State Park. Fort Davis, Texas, December 29, 2007
 Trap Mountain(?) west from Smokey Creek Trail near Trap Spring east from Mule Ear Overlook. Big Bend National Park, Texas, November 25, 2007
 Fresno Spring at evening. Big Bend National Park, Texas, November 23, 2007
 Magenta tinged prickly pears cactus on northern hill in Davis Mountains State Park. Fort Davis, Texas, December 29, 2007
 Maiden ferns at Mule Ear Spring. Big Bend National Park, Texas, November 25, 2007
 Prickly pears cactus near Fishing Beach. Sandy Hook, New Jersey, March 11, 2007
 Prickly pears cactus (zoomed) near Fishing Beach. Sandy Hook, New Jersey, March 11, 2007
 South Rim, view from Fresno Circle campsite near Dodson Trail. Big Bend National Park, Texas, November 23, 2007
 Canyon of Smokey Creek. Big Bend National Park, Texas, November 25, 2007
 Prickly pears cactus in snow near a road between White s City and Carlsbad Caverns. New Mexico, December 26, 2007
 Rocks on Devils Hall Trail in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Boot Spring Trail. Big Bend National Park, November 26, 2009
 Hiker s staircase in Pine Spring Canyon, on Devils Hall Trail. Guadalupe Mountains National Park, Texas, December 28, 2007
 Fruit of cholla cactus (cylindropuntia) on Blue Creek Trail. Big Bend National Park, November 29, 2009
 Tiny white flowers of rustweed (juniper leaf, Polypremum procumbens) on Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, July 20, 2008
 Peeling bark of Texas madrone on Devils Hall Trail in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Texas madrone (Arbutus xalapensis) on Devils Hall Trail in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Slopes of Chisos Mountains from Boot Spring Trail. Big Bend National Park, November 26, 2009
 Cliffs of Toll Mountain from Boot Spring Trail. Big Bend National Park, November 26, 2009
 Smooth white bark of Texas madrone on Devils Hall Trail in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Slopes of Chisos Mountains east from Boot Spring Trail. Big Bend National Park, November 27, 2009
 El Capitan Mountain with cholla cactus in foreground, view from upper Roadside Park. Guadalupe Mountains National Park, Texas, December 28, 2007
 Boot Canyon Trail ending at Southeast Rim. Big Bend National Park, November 27, 2009
 Blooming prickly pear cactus north from Capulin Canyon in Bandelier National Monument. New Mexico, near Los Alamos, May 24, 2008
 Agave on Smokey Creek Trail. Big Bend National Park, Texas, November 24, 2007
 Boot Rock from Boot Spring Trail. Big Bend National Park, November 28, 2009
 View of Boot Rock from Boot Spring Trail. Big Bend National Park, November 27, 2009
 Boot Rock, view from Boot Spring Trail. Big Bend National Park, November 27, 2009
 Boot Rock from Boot Spring Trail at sunrise. Big Bend National Park, November 28, 2009
 Mule Ear Peaks from Smokey Creek Trail. Big Bend National Park, Texas, November 25, 2007
 Cacti on east part of Dodson Trail. Big Bend National Park, Texas, November 23, 2007
 Flower bud of prickly pears cactus (Opuntia) in Antique Rose Emporium. Independence, Texas, April 19, 2009
 Shoot of prickly pears cactus (Opuntia) in Antique Rose Emporium in Independence. Texas, March 22, 2009
 Century plant and Elephant Tusk Mountain, view from South Rim. Big Bend National Park, Texas, November 22, 2007
 Devil s Hall in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Fresno Circle campsite near Dodson Trail at evening. Big Bend National Park, Texas, November 23, 2007
 Smokey Creek Trail north from Mule Ear Peaks. Big Bend National Park, Texas, November 25, 2007
 Vegetative shoot of prickly pears cactus (Opuntia) in Antique Rose Emporium. Independence, Texas, April 19, 2009
 Rocks in Devil s Hall in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Big rocks near Devil s Hall in Pine Spring Canyon. Guadalupe Mountains National Park, Texas, December 28, 2007
 Dallas Sierra Club on Smokey Creek Trail at rain. Big Bend National Park, Texas, November 24, 2007
 Ocotillo on Smokey Creek Trail north from Mule Ear Peaks. Big Bend National Park, Texas, November 25, 2007
 Sotol and Southeast Rim, view from east part of Dodson Trail. Big Bend National Park, Texas, November 23, 2007
 Eroded pinnacles of pink volcanic tuff looking like a miniature Bryce Canyon on Blue Creek Trail. Big Bend National Park, November 29, 2009
 Prickly pears (sabra) cactus on the roadside in Nizzanim. The Middle East, July 19, 2001
 Desert mistletoe(?) growing on ocotillo, view from Smokey Creek Trail. Big Bend National Park, Texas, November 25, 2007
 Snail feeding on a fresh young pad of prickly pears cactus (Opuntia) in Antique Rose Emporium. Independence, Texas, April 19, 2009
 Rapidly growing vegetative shoot of prickly pears cactus (Opuntia) in Antique Rose Emporium. Independence, Texas, April 19, 2009
 Sprout of prickly pears cactus (opuntia) in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, May 6, 2008
 Dried sap of prickly pears cactus (Opuntia) in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, May 8, 2009
 New growth of prickly pears cactus (Opuntia) in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, May 1, 2009
 Dry trunk of juniper near Pedernales Falls. Johnson City, Texas, November 29, 2008
 Valley of Smokey Creek, view to the east from a trail north from Mule Ear Peaks. Big Bend National Park, Texas, November 25, 2007
 Smokey Creek Trail through creosote bushes and cacti east from Mule Ear Overlook. Big Bend National Park, Texas, November 25, 2007
 Emerging sprout (new pad) of prickly pears cactus (opuntia) in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, May 6, 2008
 Blooming Prickly pears (Opuntia) cactus in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, April 26, 2009
 Spotted cucumber beetle (Diabrotica undecimpunctata) on a shoot of prickly pears cactus in Ladybird Johnson Wildflower Center. Austin, Texas, March 7, 2009
 Cactus on rocks of El Capitan Trail. Guadalupe Mountains National Park, Texas, December 27, 2007
 Hedgehog cactus near El Capitan Trail. Guadalupe Mountains National Park, Texas, December 27, 2007
 Blooming prickly pears cactus (Opuntia) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 30, 2011
 Rapidly growing vegetative shoot of prickly pears cactus (Opuntia) with fleshy, green, leaf-like phylloclades in Antique Rose Emporium. Independence, Texas, April 19, 2009
 Cushion cactus and El Capitan Mountain from a trail in Guadalupe Mountains National Park. Texas, December 27, 2007
 Prickly pears cactus (known as sabra in Israel) in downtown Beer-Sheva, at intersection of Rager and Tuvyahu Street. The Middle East, February 18, 2000
 Juniper berries in dew in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, November 5, 2009
|