 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, April 13, 2021
 Wilted giant ragweed (Ambrosia trifida) under 2,4-D Ester(?) herbicide in Washington-on-the-Brazos State Historic Site. Washington, Texas, June 20, 2022
 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
 Blooming giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 Shoot of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, August 27, 2021
 Flower buds of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Wilted giant ragweed (Ambrosia trifida) after application of a herbicide in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 21, 2020
 Green flowers with pollen of giant ragweed (Ambrosia trifida) in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 1, 2012
 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 with curled leaves 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 (Ambrosia trifida) on Kiwanis Nature Trail. College Station, Texas, April 20, 2023
 Giant ragweed (Ambrosia trifida) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 26, 2023
 Giant reed (Arundo donax) in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 22, 2022
 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
 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
 Grasshopper sleeping on ragweed in Washington-on-the-Brazos State Historic Site. Washington, Texas, October 6, 2012
 Dry leaves of giant ragweed (Ambrosia trifida) in David E. Schob Nature Preserve at 906 Ashburn Street. College Station, Texas, September 5, 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 stem of giant ragweed (Ambrosia trifida) with fungus-like dots with white hair taken from Bee Creek Park. College Station, Texas, December 9, 2020
 Giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, October 18, 2020
 Giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Seeds of giant reed (Arundo donax) in Washington-on-the-Brazos State Historic Site. Washington, Texas, November 12, 2020
 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 giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 27, 2020
 Close-up of giant reed (Arundo donax) near a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 5, 2020
 Giant reed (Arundo donax) in area of a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, November 12, 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
 Blooming poison ivy in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Fresh elm leaves in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Wildflowers on a field in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 A rusty barn in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Shoot of poison ivy in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 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
 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
 Leaves of prickly poppy in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Pink phlox flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 White phlox flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Fresh leaves of poison ivy in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Fox sedge (Carex vulpinoidea) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Fresh leaves of hackberry in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Firewheel and bull nettle in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Green milkweed together with flax in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Pink phlox flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Bluebonnet (Lupinus) flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Young leaves of elderberry in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Daisy fleabane (Erigeron) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Yellow flowers of aster family in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Bull nettle (Cnidoscolus texanus) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Indian paintbrush (Castilleja indivisa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Bluebonnet (Lupinus) and Indian paintbrush in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Prairie parsley (Polytaenia texana) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Indian paintbrush and bull nettle in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Firewheel and bull nettle flowers in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Engelmann daisy and bull nettle in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Japanese honeysuckle (Lonicera japonica) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Black caterpillars falling from a big live oak in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Young leaves of Virginia creeper in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Field of wildflowers near Ferry Road in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Various spring wildflowers behind Visitor Center in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Canada garlic (Allium canadense) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Wild Carrot (Daucus pusillus) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Prickly poppy (Argemone albiflora) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Indian paintbrush (Castilleja indivisa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Green milkweed (Asclepias viridis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Bluebonnet (Lupinus) near Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Baby blue eyes (Nemophila phacelioides) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Spores of Agaricus mushroom with a scaly cap collected in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Catkins and young leaves of oak near Ferry Road in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 White prickly poppy (Argemone albiflora) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Blooming Indian paintbrush (Castilleja indivisa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Red flowers of Indian paintbrush (Castilleja indivisa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Dry pad skeleton of prickly pear cactus (Opuntia) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Flowers of green milkweed (Asclepias viridis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Baby blue eyes (Nemophila phacelioides) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Showy evening primrose (Oenothera speciosa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Canada garlic (Allium canadense) with bulblets in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Stiff-stem flax (Linum berlandieri) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Showy evening primrose (Oenothera speciosa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Scaly brown Agaricus mushroom in a forest in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Showy evening primrose (Oenothera speciosa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Yellow and red Indian paintbrush (Castilleja indivisa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Close-up of Indian paintbrush (Castilleja indivisa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Yellow Indian paintbrush (Castilleja indivisa) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Spores of Agaricus mushroom with a scaly cap at low magnification, collected in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
 Field with bluebonnet (Lupinus) near Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Texture of a pad skeleton of prickly pear cactus (Opuntia) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Vegetative shoot of prickly pear cactus (Opuntia) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Flower of prickly poppy (Argemone albiflora) with a beetle in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 17, 2022
 Bluebonnet (Lupinus) with grass near Wildflower Loop Trail in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 4, 2022
 Flowers of white prickly poppy (Argemone albiflora) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 24, 2022
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