 Blooming giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 15, 2019
 Dry plant of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 9, 2023
 Flower buds of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Shoot of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Seedling of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 20, 2022
 Shoot of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, August 27, 2021
 Wilted giant ragweed (Ambrosia trifida) after application of a herbicide in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 21, 2020
 Wilted giant ragweed (Ambrosia trifida) under 2,4-D Ester(?) herbicide in Washington-on-the-Brazos State Historic Site. Washington, Texas, June 20, 2022
 Distorted growth of giant ragweed (Ambrosia trifida) under 2,4-D Ester(?) herbicide in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 29, 2023
 Curled leaves of giant ragweed (Ambrosia trifida) under 2,4-D Ester(?) herbicide in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 29, 2023
 Giant ragweed (Ambrosia trifida) after application of herbicide that is causing it to wilt and shrivel in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 21, 2020
 Purple bindweed and ragweed (Ambrosia) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 28, 2022
 Giant ragweed in Washington-on-the-Brazos State Historic Site. Washington, Texas, June 9, 2012
 Giant ragweed with curled leaves in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 28, 2022
 Flowers of giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 27, 2020
 Grasshopper sleeping on ragweed in Washington-on-the-Brazos State Historic Site. Washington, Texas, October 6, 2012
 Blooming giant ragweed (Ambrosia trifida) in Bee Creek Park. College Station, Texas, September 28, 2021
 Blooming giant ragweed (Ambrosia trifida) in Lick Creek Park. College Station, Texas, September 22, 2021
 Giant ragweed (Ambrosia trifida) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 26, 2023
 Dry plant of giant ragweed (Ambrosia trifida) in David E. Schob Nature Preserve at 906 Ashburn Street. College Station, Texas, September 5, 2023
 Dry leaves of giant ragweed (Ambrosia trifida) in David E. Schob Nature Preserve at 906 Ashburn Street. College Station, Texas, September 5, 2023
 Dry leaves of giant mustard (bastard cabbage, Rapistrum rugosum) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, December 8, 2012
 Flowers of balloon vine (Cardiospermum halicacabum) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Back lit flowers of balloon vine (Cardiospermum halicacabum) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Giant ragweed (Ambrosia trifida) on Kiwanis Nature Trail. College Station, Texas, April 20, 2023
 Close-up of giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Inflorescence of giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Flower spike of giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 27, 2020
 Emerging inflorescence of giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Flowers of green milkweed (Asclepias viridis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Green milkweed (Antelope horns, asclepias viridis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 1, 2012
 Multicolored flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 4, 2012
 Dry stem of giant ragweed (Ambrosia trifida) with fungus-like dots with white hair taken from Bee Creek Park. College Station, Texas, December 9, 2020
 Inflorescence of green milkweed (Antelope horns, asclepias viridis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 1, 2012
 Green milkweed (Antelope horns, asclepias viridis) with aphids in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 1, 2012
 Field of flowers near Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 4, 2012
 Solanum (nightshade) flowers in dew in Washington-on-the-Brazos State Historic Site. Washington, Texas, June 23, 2012
 Solanum (nightshade) flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, June 23, 2012
 Flowers of Chinese privet in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2012
 Flowers of Chinese privet in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 19, 2012
 Green caterpillar on flowers of wild carrot (Daucus pusillus) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 21, 2018
 Flowers of green milkweed (Asclepias viridis) on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 3, 2020
 Green grasshopper in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2010
 Flowers of Beaked burhead (Echinodorus rostratus) in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 27, 2012
 Umbrella of Prairie parsley flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 19, 2012
 Flower buds of green milkweed (Antelope horns, asclepias viridis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 1, 2012
 Flowers of green milkweed (Asclepias viridis) on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 28, 2020
 Green flowers of milkweed Asclepias viridis on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Opening flowers of Green milkweed (Asclepias viridis) in Washington-on-the-Brazos State Historic Site, near Loop Trail. Washington, Texas, April 5, 2008
 Flowers of green milkweed (Asclepias viridis) on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Green flowers of Zizotes milkweed (Asclepias oenotheroides) near Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 12, 2008
 Giant ragweed (Ambrosia trifida) with half-white leaves at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, April 14, 2024
 Cluster of green flowers of milkweed Asclepias viridis on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Close-up of flowers of green milkweed (Asclepias viridis) on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Flowers of green milkweed (Asclepias viridis) in a field on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Masses of flowers of green milkweed Asclepias viridis on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Yellow flowers of Prickly pear cactus (Opuntia) in dew in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 19, 2012
 White flowers of Bull Nettle (Cnidoscolus texanus) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2012
 Giant reed (Arundo donax) in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 22, 2022
 Green and white spurge (Euphorbia heterophylla) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Green lynx spider on Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 21, 2008
 Frightened caterpillar of white-lined sphinx moth (Hyles lineata) spitting green fluid in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 4, 2012
 Cluster of flowers of green milkweed (Asclepias viridis) in a field on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Opening flowers of green milkweed (Asclepias viridis) in a field on Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2021
 Seeds of giant reed (Arundo donax) in Washington-on-the-Brazos State Historic Site. Washington, Texas, November 12, 2020
 Giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, October 18, 2020
 Flowers of lemon beebalm (purple horsemint, Monarda citriodora) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 27, 2012
 Spider web in dew in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 23, 2012
 A road in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 23, 2012
 Green milkweed (Antelope horns, asclepias viridis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 28, 2022
 Giant reed (Arundo donax) in area of a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, November 12, 2020
 Orange butterfly near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Foggy sunrise over a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 23, 2012
 Some blooming plant near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Horse apple (osage orange, green brains) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 21, 2008
 Green lynx spider on Snow-on-the-prairie (Euphorbia bicolor) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 6, 2009
 Amaranth flowers near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Orange lantana flowers with dew in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 18, 2010
 Beeblossom flowers (Gaura) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2019
 Scarlet spiderling (Boerhavia diffusa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 23, 2012
 Snow-on-the-prairie (Euphorbia bicolor) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 23, 2012
 Turnsole (Heliotropium indicum) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Powderpuff (Mimosa strigillosa) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Field of bluebonnets and paintbrush flowers at Old Washington Town Site Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 22, 2009
 Field of bluebonnets and paintbrush flowers in mist at Old Washington Town Site Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 22, 2009
 Caltrop flower (puncturevine, Tribulus terrestris) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Yerba de Tajo (Eclipta prostrata) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Balloon Vine (Cardiospermum halicacabum) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 23, 2012
 Horse apple (osage orange) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Shoots of giant mustard (bastard cabbage, Rapistrum rugosum)(?) in a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2024
 Blooming giant mustard (bastard cabbage, Rapistrum rugosum) on a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 14, 2023
 Flowers of Zizotes milkweed (Asclepias oenotheroides) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 15, 2019
 Flowers of snow-on-the-prairie (Euphorbia bicolor) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2019
 Flowers of Morning Glory (Ipomoea cordatotriloba) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2019
 Close up of horse apple (osage orange) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Dry flowers and seeds of lemon beebalm (Monarda citriodora) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 9, 2023
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