 Violet wood sorrel (shamrock, Oxalis violacea) on Richards Loop Trail in Sam Houston National Forest. Texas, March 18, 2020
 Violet wood sorrel (shamrock, Oxalis violacea) on Richards Loop Trail in Sam Houston National Forest. Texas, March 26, 2020
 Violet wood sorrel (Oxalis violacea) both in natural light and under 365 nm ultraviolet (UV-A) blacklight from Richards Loop Trail in Sam Houston National Forest near Montgomery. Texas, September 6, 2024
 Flower of Violet Wood Sorrel (Oxalis violacea) in Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, October 22, 2011
 Back lit Violet Wood Sorrel (Oxalis violacea) in Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, October 22, 2011
 Flowers of Violet Wood Sorrel (Oxalis violacea) in Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, October 22, 2011
 Violet Wood Sorrel (Oxalis violacea) blooming at fall without leaves in Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, October 22, 2011
 Violet wood sorrel (Oxalis violacea) on Lone Star Hiking Trail in Sam Houston National Forest west from Richards. Texas, April 9, 2019
 Flower of violet wood sorrel (Oxalis violacea) on Lone Star Hiking Trail in Sam Houston National Forest west from Richards. Texas, April 9, 2019
 Yellow wood sorrel (shamrock, Oxalis dillenii?) on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Violet wood sorrel (Oxalis violacea) on Sundew Trail in Big Thicket National Preserve. Kountze, Texas, August 2, 2014
 Flowers of violet wood sorrel (Oxalis violacea, shamrock) in Little Thicket Nature Sanctuary. Cleveland, Texas, March 25, 2023
 Bloomin violet wood sorrel (Oxalis violacea, shamrock) in Little Thicket Nature Sanctuary. Cleveland, Texas, March 25, 2023
 Pink flowers of violet wood sorrel (Oxalis violacea, shamrock) in Little Thicket Nature Sanctuary. Cleveland, Texas, March 25, 2023
 Back lit flowers of violet wood sorrel (Oxalis violacea, shamrock) in Little Thicket Nature Sanctuary. Cleveland, Texas, March 25, 2023
 Violet wood sorrel (shamrock, Oxalis violacea?) in Big Thicket park on Sundew Trail. Texas, October 11, 2008
 Yellow wood sorrel (Oxalis stricta) on Richards Loop Trail in Sam Houston National Forest. Texas, March 26, 2020
 Yellow wood sorrel (Oxalis stricta) on Richards Loop Trail in Sam Houston National Forest. Texas, March 18, 2020
 Flowers of yellow wood sorrel (Oxalis stricta) on Richards Loop Trail in Sam Houston National Forest. Texas, March 18, 2020
 Violet wood sorrel (shamrock, Oxalis violacea?) in Mercer Arboretum and Botanical Gardens. Humble (Houston area), Texas, April 5, 2009
 Violet wood sorrel (Oxalis violacea, shamrock) on Hoots Hollow Trail in Brazos Bend State Park. Needville, Texas, February 15, 2020
 Pink flower of Violet wood sorrel (Oxalis violacea, shamrock) on Prairie Trail in Brazos Bend State Park. Needville, Texas, April 22, 2008
 Blooming yellow wood sorrel (shamrock, Oxalis dillenii?) on Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, March 29, 2009
 Pink flowers of Violet wood sorrel (Oxalis violacea, shamrock) on Hoots Hollow Trail in Brazos Bend State Park. Needville, Texas, February 15, 2020
 Violet woodsorrel (Oxalis violacea) on Lone Star Hiking Trail near Pole Creek in Sam Houston National Forest. Richards, Texas, March 1, 2019
 Leaves of violet woodsorrel (Oxalis violacea) on Lone Star Hiking Trail near Pole Creek in Sam Houston National Forest. Richards, Texas, March 1, 2019
 Pattern of leaves of violet woodsorrel (Oxalis violacea) on Lone Star Hiking Trail near Pole Creek in Sam Houston National Forest. Richards, Texas, March 1, 2019
 Underside of a leaf of violet woodsorrel (Oxalis violacea) on Lone Star Hiking Trail near Pole Creek in Sam Houston National Forest. Richards, Texas, March 1, 2019
 Carpet of leaves of violet woodsorrel (Oxalis violacea) on Lone Star Hiking Trail near Pole Creek in Sam Houston National Forest. Richards, Texas, March 1, 2019
 Yellow wood sorrel (shamrock, Oxalis dillenii?) in Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, May 26, 2012
 Violet wood sorrel (shamrock, Oxalis violacea?) near a pond in Washington-on-the-Brazos State Historic Site. Washington, Texas, September 21, 2008
 Violet Wood Sorrel (Oxalis violacea) in dew blooming at fall without leaves in Washington-on-the-Brazos State Historic Site. Washington, Texas, October 20, 2013
 Blooming yellow wood sorrel (shamrock, Oxalis dillenii?) on Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, October 13, 2012
 Yellow flower of wood sorrel (shamrock, Oxalis dillenii?) on Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, October 13, 2012
 Pink wood sorrel (shamrock, Oxalis violacea?) in Mercer Arboretum and Botanical Gardens. Humble (Houston area), Texas, February 8, 2009
 Tiny purple flower of Violet wood sorrel (shamrock, Oxalis) on Deer Run Trail in Lick Creek Park. College Station, Texas, September 30, 2008
 Blooming yellow wood sorrel (shamrock, Oxalis dillenii?) with soldier flies (Stratiomyidae) in Big Thicket park on Sandhill Loop Trail. Texas, March 23, 2008
 Pink flowers of wood sorrel (Oxalis) on Stubblefield section of Lone Star hiking trail north from Trailhead No. 6 in Sam Houston National Forest. Texas, April 2, 2022
 Yellow wood sorrel (Oxalis) near Pole Creek on North Wilderness Trail of Little Lake Creek Wilderness in Sam Houston National Forest north from Montgomery. Texas, March 26, 2022
 Blooming slender trillium (Trillium gracile) and yellow wood sorrel (Oxalis) on Fringe Tree Trail in Little Thicket Nature Sanctuary. Cleveland, Texas, March 23, 2024
 Flowers of yellow wood sorrel (Oxalis) near Pole Creek on North Wilderness Trail of Little Lake Creek Wilderness in Sam Houston National Forest north from Montgomery. Texas, March 26, 2022
 Common blue violet (Viola sororia) on Richards Loop Trail in Sam Houston National Forest. Texas, March 3, 2024
 Back-lit purple flower of wood sorrel in Sam Houston National Forest on Little Lake Creek Loop Trail. Richards, Texas, April 4, 2010.
 Flower of common blue violet (Viola sororia) on Richards Loop Trail in Sam Houston National Forest. Texas, March 3, 2024
 Purple flowers of Violet wood sorrel (shamrock, Oxalis) in TAMU Horticultural Gardens in Texas A and M University. College Station, Texas, January 9, 2009
 Common yellow wood sorrel (Oxalis stricta) on Lost Pines Trail in Bastrop State Park. Bastrop, Texas, March 14, 2019
 Sorrel rust fungus (Puccinia oxalidis) on yellow oxalis (Oxalis stricta) in wet area on Raccoon Run Trail in Lick Creek Park. College Station, Texas, March 26, 2019
 Yellow flowers of common wood sorrel (Oxalis stricta) on Lost Pines Trail in Bastrop State Park. Bastrop, Texas, March 14, 2019
 Blooming common yellow wood sorrel (Oxalis stricta) on Lost Pines Trail in Bastrop State Park. Bastrop, Texas, March 14, 2019
 Leaves of yellow oxalis (Oxalis stricta) with sorrel rust fungus (Puccinia oxalidis) in wet area on Raccoon Run Trail in Lick Creek Park. College Station, Texas, March 26, 2019
 Common yellow oxalis (Oxalis stricta) with sorrel rust fungus (Puccinia oxalidis) in wet area on Raccoon Run Trail in Lick Creek Park. College Station, Texas, March 22, 2019
 Common yellow oxalis (Oxalis stricta) with sorrel rust fungus (Puccinia oxalidis) in wet area on Raccoon Run Trail in Lick Creek Park. College Station, Texas, March 26, 2019
 Close up of yellow flowers of common wood sorrel (Oxalis stricta) on Lost Pines Trail in Bastrop State Park. Bastrop, Texas, March 14, 2019
 Sorrel rust fungus (Puccinia oxalidis) on yellow oxalis (Oxalis stricta) in Bee Creek Park. College Station, Texas, March 29, 2022
 Underside of leaves of wood sorrel Oxalis stricta with rust fungus Puccinia oxalidis in Bee Creek Park. College Station, Texas, March 29, 2022
 Flower of blue violet (Viola) in a pine forest at Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, March 8, 2019
 Missouri violet (Viola missouriensis) on Little Lake Creek Loop Trail in Sam Houston National Forest. Richards, Texas, March 8, 2020
 Spiderwort (Tradescantia) and yellow wood sorrel (oxalis) in Washington-on-the-Brazos State Historic Site. Washington, Texas, March 6, 2022
 Wood sorrel (Oxalis acetosella, Kislitsa in Russian) carpeting a forest in Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2011
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 10, 2016
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 20, 2017
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) with flowers in Sosnovka Park. Saint Petersburg, Russia, May 20, 2017
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Tarkhovka near Sestroretsk. West from Saint Petersburg, Russia, May 13, 2019
 Flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 10, 2016
 Blooming wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 20, 2017
 Flower of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 20, 2017
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) in flower in Sosnovka Park. Saint Petersburg, Russia, May 20, 2017
 Blooming wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 10, 2016
 White flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 20, 2017
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Dubki Park. Sestroretsk, a suburb of Saint Petersburg, Russia, May 19, 2011
 Carpet of flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 20, 2017
 Carpet of flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sosnovka Park. Saint Petersburg, Russia, May 10, 2016
 Blooming wood sorrel (Oxalis) on Angliyskaya Alley in a park of Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2011
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Dubki Park. Sestroretsk, a suburb of Saint Petersburg, Russia, May 20, 2015
 Shoot of peppervine on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Violet wood sorrel blooming at fall (without leaves) in Mercer Arboretum and Botanical Gardens. Humble (Houston area), Texas, September 25, 2010
 Violet wood sorrel blooming at fall without leaves in Mercer Arboretum and Botanical Gardens. Humble (Houston area), Texas, September 5, 2009
 Wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sobstvennaya Dacha Park. Old Peterhof, west from Saint Petersburg, Russia, May 17, 2019
 White flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Pavlovsk Park, suburb of Saint Petersburg. Russia, May 15, 2011
 Pink variety of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2017
 Blooming wood sorrel (Oxalis acetosella, Kislitsa in Russian) in a park of Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2011
 Flower of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Dubki Park. Sestroretsk, a suburb of Saint Petersburg, Russia, May 19, 2011
 Pink flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2017
 Blooming wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Dubki Park. Sestroretsk, a suburb of Saint Petersburg, Russia, May 20, 2015
 Shoot of mustang grape on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Blooming blackberry on Road FS 203 near on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Shoot of hickory on Road FS 203 near on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Young reddish leaves of oak on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Some small grass on Road FS 203 near on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Flower of blackberry on Forest Service Road 203 on Richards Loop Trail in Sam Houston National Forest. Texas, March 3, 2024
 Flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sobstvennaya Dacha Park. Old Peterhof, west from Saint Petersburg, Russia, May 17, 2019
 Blooming wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Upper Park in Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2017
 Pink and white flowers of wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2017
 White flowers of wood sorrel (Oxalis acetosella, Kislitsa in Russian) in a park of Lomonosov (Oranienbaum). West from Saint Petersburg, Russia, May 23, 2011
 Blooming wood sorrel (Oxalis acetosella, Russian name Kislitsa) in Sobstvennaya Dacha Park. Old Peterhof, west from Saint Petersburg, Russia, May 17, 2019
 Shrinken wood of an oak branch with heart rot fungus Inonotus andersonii on South Wilderness Loop Trail at Little Lake Creek Wilderness in Sam Houston National Forest near Richards. Texas, January 1, 2024
 Young leaves of hickory on Road FS 203 near on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Globe beak-rush (Rhynchospora) on Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
 Woolly-white (Hymenopappus) on Road FS 203 near Richards Loop Trail in Sam Houston National Forest. Texas, March 30, 2024
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