 Close-up of a flower of Claret cup cactus in Ladybird Johnson Wildflower Center. Austin, Texas, March 7, 2009
 Claret cup cactus (Echinocereus triglochidiatus) in Ladybird Johnson Wildflower Center. Austin, Texas, March 7, 2009
 Yellow flowers of Prickly pear cactus (Opuntia) on Savanna Meadow Trail in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Orange flowers of Prickly pear cactus (Opuntia) on Savanna Meadow Trail in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Spotted cucumber beetle (Diabrotica undecimpunctata) on a shoot of prickly pears cactus in Ladybird Johnson Wildflower Center. Austin, Texas, March 7, 2009
 Yellow and orange flowers of Engelmann prickly pear cactus (Opuntia phaeacantha var. discata) on Savanna Meadow Trail in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Dry aster seeds in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Redeye prickly pear cactus (Engelmann prickly pear, Opuntia phaeacantha var. discata) on Savanna Meadow Trail in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Tulipan del monte (Hibiscus cardiophyllus) in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Devil s shoestring (Nolina lindhemeriana) in Ladybird Johnson Wildflower Center. Austin, Texas, March 7, 2009
 Common trumpet creeper (Foxglove vine, Campsis radicans) in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Candelilla plant (Desert Candle, Euphorbia antisyphillitica) in Ladybird Johnson Wildflower Center. Austin, Texas, March 7, 2009
 Milkweed (Antelope horns, Asclepias asperula) on Savanna Meadow Trail in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Succulent in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Reakirt s Blue (Echinargus isola) butterfly on Antelope horns milkweed (Asclepias asperula) on Savanna Meadow Trail in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Palafoxia callosa in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Water cistern in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Red succulent flowers in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Palafoxia hookeriana flower in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Mistflower (Eupatorium coelestinum) in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Water-primrose (Ludwigia) in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Crag lily (Anthericum torreyi) in Ladybird Johnson Wildflower Center. Austin, Texas, July 26, 2008
 Netted milkvine (Matelea reticulata) flower, with flat starlike green petal lobes with netlike markings and the shiny pearly white central dome, on Woodland Trail in Ladybird Johnson Wildflower Center. Austin, Texas, May 10, 2009
 Cactus in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 Fruits of sand button (creeping thorn rose, Neurada procumbens, local name saadan) taken from desert on the border of Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, March 14, 2015
 Fruits and a flower of sand button (creeping thorn rose, Neurada procumbens, local name saadan) taken from desert on the border of Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, March 14, 2015
 Nipple cactus (Missouri foxtail cactus, Escobaria missouriensis, Coryphantha missouriensis) with fruits on Moore s Hill Outcrop at FM Road 3090 near Navasota. Texas, October 1, 2013
 Nipple cactus (Missouri foxtail cactus, Escobaria missouriensis, Coryphantha missouriensis) with red fruits on Moore s Hill Outcrop at FM Road 3090 near Navasota. Texas, April 17, 2022
 Fruits of Nipple cactus (Missouri foxtail cactus, Escobaria missouriensis, Coryphantha missouriensis) on Moore s Hill Outcrop at FM Road 3090 near Navasota. Texas, October 1, 2013
 Nipple cactus (Missouri foxtail cactus, Escobaria missouriensis, Coryphantha missouriensis) with red fruits on Moore s Hill Outcrop at FM Road 3090 near Navasota. Texas, October 20, 2013
 Nipple cactus (Missouri foxtail cactus, Escobaria missouriensis, Coryphantha missouriensis) with fruits on Moore s Hill Outcrop at FM Road 3090 near Navasota. Texas, August 1, 2013
 Close up of Nipple cactus (Missouri foxtail cactus, Escobaria missouriensis, Coryphantha missouriensis) with fruits on Moore s Hill Outcrop at FM Road 3090 near Navasota. Texas, October 1, 2013
 Nipple cactus (Missouri foxtail cactus, Escobaria missouriensis, Coryphantha missouriensis) with red fruits and flower buds on Moore s Hill Outcrop at FM Road 3090 near Navasota. Texas, April 17, 2022
 Button lichen (Buellia) on a limestone rock in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
 Button lichen (Buellia) on limestone near the river in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
 Button lichen (Buellia) on a limestone rock in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
 Patches of button lichen (Buellia) on a limestone rock in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
 Button lichen (Buellia) on a mossy limestone rock in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
 Button lichen (Buellia) on limestone rock near the river in Pedernales Falls State Park. Johnson City, Texas, January 11, 2019
 Button like fruits of Bienertia cycloptera on a beach in Abu Samra, near the border. Southern Qatar, November 29, 2014
 Button like fruits of Bienertia cycloptera on a beach in Abu Samra, near the border. Southern Qatar, November 29, 2014
 Christmas cholla cactus (Tasajillo, Opuntia leptocaulis) on Homestead Trail in McKinney Falls State Park. Austin, Texas, October 26, 2008
 Button like fruits of Bienertia sinuspersici on a beach near Zubara archeological site. Northern Qatar, October 24, 2014
 Dwarf rosette lichen Physcia neogaea on a dry pad of prickly pear cactus in prairie in McKinney Roughs Nature Park near Austin. Texas, March 17, 2021
 Dwarf rosette lichen Physcia neogaea on a dry pad of prickly pear cactus (Opuntia) in McKinney Roughs Nature Park near Austin. Texas, March 17, 2021
 Slender orange-bush lichen (Teloschistes exilis) together with Parmotrema and Physcia on an old pad of prickly pear cactus in McKinney Roughs Nature Park near Austin. Texas, March 17, 2021
 Cactus with edible fruits at Ben Gurion Boulevard. Beer-Sheva, the Middle East, August 24, 2002
 Fruits of Christmas cholla cactus (Tasajillo, Opuntia leptocaulis) in a ranch at 7278 Batts Ferry Road. College Station, Texas, August 1, 2014
 Nipple cactus (Coryphantha) with fruits in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, June 12, 2008
 Flower and fruits of Christmas cholla cactus (Tasajillo, Opuntia leptocaulis) in a ranch at 7278 Batts Ferry Road. College Station, Texas, August 1, 2014
 Spiny button-like flowerheads of button snakeroot (yuccaleaf snakeroot, Eryngium yuccifolium) in Lick Creek Park. College Station, Texas, May 22, 2012
 Spiny button-like flowerheads of button snakeroot (yuccaleaf snakeroot, Eryngium yuccifolium) in Lick Creek Park. College Station, Texas, June 13, 2022
 Fruits of Ricinus communis (Castorbean, Castor Oil plant, Palma Christi, Ricin, Wonder tree, Krapata) near Beach Area of Pedernales Falls State Park. Johnson City, Texas, November 2, 2008
 Johnson grass (Sorghum halepense)(?) on Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, February 26, 2016
 Sand button (creeping thorn rose, Neurada procumbens, local name saadan) taken from periphery of Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, March 14, 2015
 Spiny button-like flowerheads of button snakeroot (yuccaleaf snakeroot, Eryngium yuccifolium) near Deer Run Trail in Lick Creek Park. College Station, Texas, June 8, 2008
 Spiny button-like flowerheads of button snakeroot (yuccaleaf snakeroot, Eryngium yuccifolium) near Deer Run Trail in Lick Creek Park. College Station, Texas, July 4, 2013
 Spike of Johnson grass (Sorghum halepense)(?) on Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, February 26, 2016
 Close up of Johnson grass (Sorghum halepense)(?) on Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, February 26, 2016
 Spikelets of Johnson grass (Sorghum halepense)(?) on Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, February 26, 2016
 Ponds of Pedernales Falls. Johnson City, Texas, November 7, 2009
 Pink rose in Zilker Botanical Gardens. Austin, Texas, May 10, 2009
 Loop 360 Pennybacker Bridge and Lake Austin at morning. Austin, Texas, July 26, 2008
 Spiny button-like flower heads in umbels of button snakeroot (yuccaleaf snakeroot, Eryngium yuccifolium) in Lick Creek park, on Deer Run Trail. College Station, June 15, 2008
 Shoot of sand button (creeping thorn rose, Neurada procumbens, local name saadan) taken from desert on the border of Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. Qatar, March 14, 2015
 Johnson grass (Sorghum halepense) on Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. South-western Qatar, November 15, 2014
 Cypress pool below Pedernales Falls. Johnson City, Texas, November 7, 2009
 Cypress roots below Pedernales Falls. Johnson City, Texas, November 7, 2009
 Cypress pool below Pedernales Falls. Johnson City, Texas, November 7, 2009
 Water stream near Pedernales Falls. Johnson City, Texas, November 7, 2009
 Replica of an old barn in Zilker Botanical Gardens. Austin, Texas, November 7, 2009
 Artificial waterfall in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 Orange tiger lily in Zilker Botanical Gardens. Austin, Texas, May 10, 2009
 Pink water lily in Zilker Botanical Gardens. Austin, Texas, May 10, 2009
 Seeds of Johnson grass (Sorghum halepense) on Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. South-western Qatar, November 15, 2014
 Tombs of Thomas and Martha Johnson in Boonville Cemetery. Bryan, Texas, December 8, 2009
 Cypress roots between stones below Pedernales Falls. Johnson City, Texas, November 7, 2009
 Cactus with water drops in Antique Rose Emporium. Independence, Texas, December 12, 2009
 Cholla cactus (cylindropuntia) in Antique Rose Emporium. Independence, Texas, August 15, 2009
 Apical meristem of a cactus in Antique Rose Emporium. Independence, Texas, August 15, 2009
 Angel s trumpet (Brugmansia) in Zilker Botanical Gardens. Austin, Texas, November 7, 2009
 Buffalo bur (Solanum rostratum) in McKinney Falls State Park near Austin. Texas, May 10, 2009
 Waterfall in Japanese garden in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 Twin artificial waterfall in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 Crossvine (Bignonia capreolata) in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 Close up of seeds of Johnson grass (Sorghum halepense) taken from Green Circles (center-pivot irrigation) in Irkhaya (Irkaya) Farms. South-western Qatar, November 15, 2014
 Apical meristem of a potted cactus in Antique Rose Emporium. Independence, Texas, August 15, 2009
 Blooming cherry like tree in McKinney Falls State Park. Austin, Texas, March 7, 2009
 White flower of lily family in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 Fern fiddlehead in prehistoric garden in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 River below Beach Area in Pedernales Falls State Park. Johnson City, Texas, November 7, 2009
 Cypress below Beach Area in Pedernales Falls State Park. Johnson City, Texas, November 7, 2009
 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
 Blue curls (Fiddleneck, Phacelia congesta) in McKinney Falls State Park near Austin. Texas, May 10, 2009
 Blooming mountain laurel (Sophora secundiflora) in Zilker Botanical Gardens, Austin, Texas, March 7, 2009
 Water speedwell (Veronica anagalis-aquatica) in McKinney Falls State Park near Austin. Texas, May 10, 2009
 Cypress needles below Beach Area in Pedernales Falls State Park. Johnson City, Texas, November 7, 2009
 Cypresses and rocks below Beach Area in Pedernales Falls State Park. Johnson City, Texas, November 7, 2009
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