 Thorny basal leaves of thistle (Cirsium) in Bee Creek Park. College Station, Texas, January 28, 2023
 Thorny rosette of leaves of some thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 28, 2023
 Winter rosette of leaves of some thistle (Cirsium) in Bee Creek Park. College Station, Texas, January 28, 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
 Rosette of leaves of yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, January 10, 2024
 Thorny leaves of thistle (Cirsium) in Lick Creek Park. College Station, Texas, February 13, 2024
 Thorny shoot of thistle (Cirsium) in Lick Creek Park. College Station, Texas, March 7, 2023
 Winter rosette of thistle (Cirsium) in dew in Lick Creek Park. College Station, Texas, January 23, 2023
 Winter rosette of leaves of thistle (Cirsium) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, January 16, 2023
 Thorny leaves of some thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 28, 2023
 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
 Rosette of thistle (Cirsium) in Lick Creek Park. College Station, Texas, February 27, 2023
 Winter rosette of leaves of thistle (Cirsium) in Lick Creek Park. College Station, Texas, February 1, 2021
 Winter rosette of leaves of thistle (Cirsium) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, February 15, 2023
 Rosette of prickly leaves of thistle (Cirsium) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, February 15, 2023
 Pattern of winter rosette of leaves of some thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 28, 2023
 Central area of rosette of prickly leaves of thistle (Cirsium) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, February 15, 2023
 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) with freeze in Lick Creek Park. College Station, Texas, January 3, 2022
 Winter rosette of yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 11, 2021
 Winter rosette of yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, February 25, 2021
 Thorny leaves of a rosette of thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 11, 2023
 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
 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
 Basal leaves of yellow thistle (Bull thistle, Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, February 25, 2021
 Seeds of yellow thistle (Bull thistle, Cirsium horridulum) on sewage line right-of-way in Lick Creek Park. College Station, Texas, May 2, 2023
 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
 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 forest opening over a sewage line in Lick Creek Park. College Station, Texas, March 31, 2023
 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
 Rosette and yellow flowers of bull thistle (Cirsium horridulum) on a pipeline clearing in Lick Creek Park. College Station, Texas, March 24, 2021
 Thorny winter rosette of a thistle in Bastrop State Park. Bastrop, Texas, January 5, 2013
 Thorny rosette of leaves of a thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2022
 Rosette of leaves of thistle (Cirsium) on roadside near Kavgolovskoe Lake. North from Saint Petersburg, Russia, May 3, 2017
 Leaves of summer-blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, March 12, 2024
 Thorny rosette of thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 11, 2023
 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
 Some winter rosette of leaves in Bee Creek Park. College Station, Texas, January 27, 2023
 Pattern of a thorny rosette of thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 11, 2023
 Center part of a thorny rosette of thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 11, 2023
 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
 Yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 5, 2018
 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, March 31, 2024
 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 5, 2019
 Rosette of leaves of thistle (Cirsium) in a pine forest on Caney Creek section of Lone Star Hiking Trail in Sam Houston National Forest near Huntsville, Texas, May 19, 2018
 Blooming yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 5, 2019
 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 11, 2018
 Flower bud of yellow thistle (Bull thistle, Cirsium horridulum) in Lick Creek Park. College Station, Texas, April 14, 2019
 Thorny rosette of leaves of a thistle on Forest Service Road 231 near North Wilderness Trail of Little Lake Creek Wilderness in Sam Houston National Forest north from Montgomery. Texas, March 5, 2022
 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
 Rosette of leaves of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2024
 Flower of yellow thistle (Bull thistle, Cirsium horridulum) with a bronze beetle in Lick Creek Park. College Station, Texas, April 5, 2019
 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
 Yellow thistle (Bull thistle, Cirsium horridulum) on a recently built pipeline in Lick Creek Park. College Station, Texas, April 12, 2021
 Flower bud of yellow thistle (Bull thistle, Cirsium horridulum) on Post Oak Trail in Lick Creek Park. College Station, Texas, March 26, 2019
 Rosette of bull thistle (Cirsium horridulum)(?) on a golf course on campus of Texas A and M University. College Station, Texas, February 14, 2021
 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
 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
 Thorny basal leaves of thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, February 11, 2023
 Winter rosette of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, January 24, 2021
 Young leaves of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 14, 2023
 Young leaves of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2023
 Basal rosette of leaves in Lick Creek Park. College Station, Texas, February 27, 2023
 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
 Thorny winter rosette of a thistle in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 1, 2020
 Young leaves and flower buds of thistle (Cirsium) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2023
 Rosette of leaves of Coreopsis(?) or may be Bidens in Lick Creek Park. College Station, Texas, March 2, 2023
 Thistle (Cirsium engelmannii) flower in Lick Creek Park. College Station, Texas, June 30, 2012
 Thistle (Cirsium engelmannii) flower bud in Lick Creek Park. College Station, Texas, June 10, 2012
 Thistle (Cirsium engelmannii) heads in Lick Creek Park. College Station, Texas, June 22, 2012
 Florets of a thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, July 7, 2012
 Blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 22, 2012
 Fluffy seeds of thistle (Cirsium) in Lick Creek Park. College Station, Texas, August 1, 2021
 Flower of thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 22, 2012
 Flower of thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 26, 2012
 Blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 26, 2012
 Young leaves of thistle (Cirsium) on a trailway near Birch Creek Unit of Somerville Lake State Park. Texas, March 2, 2024
 Leaves of a thistle under small oaks in Lick Creek Park. College Station, Texas, January 3, 2021
 Rosette of leaves of a plant of sunflower family in Lick Creek Park. College Station, Texas, March 2, 2023
 Thistle (Cirsium engelmannii) flower buds in Lick Creek Park. College Station, Texas, June 10, 2012
 Thistle (Cirsium engelmannii) on sewage line right of way in Lick Creek Park. College Station, Texas, July 7, 2012
 Thistle flower heads (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, July 7, 2012
 Fluffy seeds of bull thistle (Cirsium horridulum) in Lick Creek Park. College Station, Texas, May 7, 2018
 Summer-blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, July 10, 2014
 Summer-blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 22, 2022
 Close up of a flower of thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 22, 2012
 Summer-blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, July 3, 2014
 Close up of a thistle (Cirsium engelmannii) flower bud in Lick Creek Park. College Station, Texas, June 10, 2012
 Summer-blooming thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 27, 2022
 Spiny flower bud of a thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 20, 2012
 Globular flower bud of a thistle (Cirsium engelmannii) in Lick Creek Park. College Station, Texas, June 10, 2012
 Rosette of leaves of lyreleaf sage (Salvia lyrata) in Lick Creek Park. College Station, Texas, March 2, 2023
 Rosette of leaves of lyreleaf sage (Salvia lyrata) in Lick Creek Park. College Station, Texas, February 27, 2023
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