 Yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, March 31, 2024
 Yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 24, 2021
 Yellow thistle (Bull thistle, Cirsium horridulum) on Post Oak Trail in Lick Creek Park. College Station, Texas, March 26, 2019
 Flower bud of yellow thistle (Bull thistle, Cirsium horridulum) on Post Oak Trail in Lick Creek Park. College Station, Texas, March 26, 2019
 Yellow thistle (Bull thistle, Cirsium horridulum) on a forest opening over a sewage line in Lick Creek Park. College Station, Texas, March 31, 2023
 Winter rosette of yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 11, 2021
 Yellow thistle (Bull thistle, Cirsium horridulum) in Lake Bryan Park. Bryan, Texas, March 20, 2010.
 Yellow thistle (Bull thistle, Cirsium horridulum)(?) in Bastrop State Park. Bastrop, Texas, March 17, 2018
 Yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 5, 2019
 Yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 6, 2022
 Yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 12, 2024
 Yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 18, 2022
 Yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 5, 2018
 Yellow thistle (Bull thistle, Cirsium horridulum)(?) on mulch in a tree utilization site in Bastrop State Park. Bastrop, Texas, March 17, 2018
 Yellow thistle (Bull thistle, Cirsium horridulum) on Richards Loop Trail in Sam Houston National Forest. Texas, April 13, 2024
 Blooming yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 5, 2019
 Flower bud of yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 11, 2018
 Flower of yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 5, 2019
 Flower bud of yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 14, 2019
 Yellow thistle (Bull thistle, Cirsium horridulum) on Lone Star Trail in Sam Houston National Forest, near Huntsville. Texas, April 8, 2018
 Rosette of leaves of yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, January 10, 2024
 Seeds of yellow thistle (Bull thistle, Cirsium horridulum) on sewage line right-of-way in Lick Creek Park. College Station, Texas, May 2, 2023
 Fluffy seeds of yellow thistle (Bull thistle, Cirsium horridulum) on sewage line right-of-way in Lick Creek Park. College Station, Texas, May 2, 2023
 Yellow thistle (Bull thistle, Cirsium horridulum) on a recently built pipeline in Lick Creek Park. College Station, Texas, April 12, 2021
 Flower of yellow thistle (Bull thistle, Cirsium horridulum) with a bronze beetle in Lick Creek Park. College Station, Texas, April 5, 2019
 Arrangement of seeds of yellow thistle (Bull thistle, Cirsium horridulum) on sewage line right-of-way in Lick Creek Park. College Station, Texas, May 2, 2023
 Metallic beetles in yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline right-of-way in Lick Creek Park. College Station, Texas, April 12, 2021
 Basal leaves of yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, February 25, 2021
 Winter rosette of yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, February 25, 2021
 Immature seed head of yellow thistle (Bull thistle, Cirsium horridulum) on sewage line right-of-way in Lick Creek Park. College Station, Texas, May 2, 2023
 Large thorny rosette of yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, February 25, 2021
 Blooming yellow thistle (Bull thistle, Cirsium horridulum) in Bastrop State Park. Bastrop, Texas, April 25, 2021
 Yellow spiny thistle (Bull thistle, Cirsium horridulum) at sunrise in Lake Bryan Park. Bryan, Texas, April 13, 2010
 Yellow flowers of bull thistle (Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 24, 2021
 Rosette and yellow flowers of bull thistle (Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 24, 2021
 Side view of a large yellow flower of bull thistle (Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 24, 2021
 Yellow flower of bull thistle (Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 18, 2022
 Leaves of bull thistle (Cirsium horridulum) in area of a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 20, 2022
 Rosette of leaves of bull thistle (Cirsium horridulum) in area of a former pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 20, 2022
 Large flower bud of bull thistle (Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 24, 2021
 Opening flower of bull thistle (Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 24, 2021
 Fluffy seeds of bull thistle (Cirsium horridulum) in Lick Creek Park. College Station, Texas, May 7, 2018
 Top view of Bull thistle (Cirsium horridulum) on Richards Loop Trail in Sam Houston National Forest. Texas, April 9, 2022
 Blooming bull thistle (Cirsium horridulum) on Richards Loop Trail in Sam Houston National Forest. Texas, April 9, 2022
 Winter rosette of bull thistle (Cirsium horridulum) with freeze in Lick Creek Park. College Station, Texas, January 3, 2022
 Bull thistle (Cirsium horridulum) in Bastrop State Park. Bastrop, Texas, April 25, 2021
 Leaves of bull thistle (Cirsium horridulum) in ultraviolet light on a sewage line right of way in Lick Creek Park. College Station, Texas, November 15, 2024
 Bull thistle (Cirsium horridulum)(?) on a golf course on campus of Texas A and M University. College Station, Texas, February 14, 2021
 Icy rosettes of bull thistle (Cirsium horridulum)(?) on a golf course on campus of Texas A and M University. College Station, Texas, February 14, 2021
 Rosette of bull thistle (Cirsium horridulum)(?) on a golf course on campus of Texas A and M University. College Station, Texas, February 14, 2021
 Rosette of basal leaves of bull thistle (Cirsium horridulum) in ultraviolet light on a sewage line right of way in Lick Creek Park. College Station, Texas, November 15, 2024
 Winter rosette of bull thistle (Cirsium horridulum) when exposed to regular daylight as well as when illuminated by a 365 nm ultraviolet (UV-A) blacklight on a sewage line right of way in Lick Creek Park. College Station, Texas, November 15, 2024
 Basal leaves of bull thistle (Cirsium horridulum) when exposed to regular daylight as well as when illuminated by a 365 nm ultraviolet (UV-A) blacklight on a sewage line right of way in Lick Creek Park. College Station, Texas, November 15, 2024
 Thorny leaves of bull thistle (Cirsium horridulum) when exposed to regular daylight as well as when illuminated by a 365 nm ultraviolet (UV-A) blacklight on a sewage line right of way in Lick Creek Park. College Station, Texas, November 15, 2024
 Smaller rosette of basal leaves of bull thistle (Cirsium horridulum) when exposed to regular daylight as well as when illuminated by a 365 nm ultraviolet (UV-A) blacklight on a sewage line right of way in Lick Creek Park. College Station, Texas, November 15, 2024
 Bull thistle (Cirsium horridulum) at Lake Somerville Trailway near Birch Creek Unit of Somerville Lake State Park. Texas, April 5, 2020
 Central area of rosette of basal leaves of bull thistle (Cirsium horridulum) when exposed to regular daylight as well as when illuminated by a 365 nm ultraviolet (UV-A) blacklight on a sewage line right of way in Lick Creek Park. College Station, Texas, November 15, 2024
 Bull thistle (Cirsium horridulum) on a forest clearing on Caney Creek Trail (Little Lake Creek Loop Trail) in Sam Houston National Forest north from Montgomery. Texas, April 11, 2021
 Thistle flower (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 3, 2009
 Flower bud of a thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 29, 2023
 Young leaves of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 14, 2023
 Large shoot of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2023
 Rosette of leaves of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2024
 Young leaves of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2023
 Young leaves and flower buds of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2023
 Flower bud of Texas thistle (Cirsium texanum) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 22, 2021
 Thistle flower (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 5, 2022
 Flower of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2023
 Thistle (Cirsium engelmannii) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 12, 2018
 Blooming thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 13, 2023
 Thistle flower (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 21, 2018
 Basal leaves of bull thistle(?) in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 20, 2022
 Winter rosette of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 24, 2021
 Fluffy seeds of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, June 20, 2022
 Thorny leaves of some thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 28, 2023
 Dry seed heads of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, June 20, 2022
 Thorny rosette of leaves of some thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 28, 2023
 Batterfly on a thistle flower (Cirsium) in a dried pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 25, 2020
 Pattern of winter rosette of leaves of some thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 28, 2023
 Yellow flower of sow thistle (Sonchus oleraceus) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2022
 Field thistle (Cirsium) east from Toksovo, 10 miles north from Saint Petersburg. Russia, July 9, 2009
 Flower buds of Texas thistle (Cirsium texanum) in Washington-on-the-Brazos State Historic Site. Washington, Texas, April 3, 2021
 Thorny shoot of thistle (Cirsium) in Lick Creek Park. College Station, Texas, March 7, 2023
 Flower bud of summer-blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, March 31, 2024
 Leaves of summer-blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, March 12, 2024
 Flower of thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 9, 2009
 Yellow distaff-thistle (Atractylis carduus, local names jalwa, laymoony, shuwwaykh) near a road north from Ash Shahaniyah. Western Qatar, March 1, 2014
 Young leaves of thistle (Cirsium) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 2, 2024
 Flower buds of a thistle (Cirsium) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 26, 2023
 Blister beetle (Meloidae) in genus Nemognatha on thistle flower in Washington-on-the-Brazos State Historic Site. Washington, Texas, May 16, 2009
 Crab spider on a thistle Robinson Ferry Road in Washington-on-the-Brazos State Historic Site. Washington, Texas, July 12, 2014
 Texas longhorn cow in the Bar 55 Ranch, view from Whitman Road south from Washington. Texas, March 30, 2008
 Texas longhorns among bluebonnet flowers in the Bar 55 Ranch, view from Whitman Road south from Washington. Texas, March 30, 2008
 Thorny winter rosette of a thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2020
 Thorny rosette of leaves of a thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2022
 Rosette of thistle (Cirsium) in Lick Creek Park. College Station, Texas, February 27, 2023
 Thistle (Cirsium) on Richards Loop Trail in Sam Houston National Forest. Texas, April 21, 2022
 Flower of thistle (Cirsium) in Lick Creek Park. College Station, Texas, August 4, 2021
 Fluffy seeds of thistle (Cirsium) in Lick Creek Park. College Station, Texas, May 20, 2014
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