[Sow Thistles: The Genus Sonchus West of the Cascade Mountains of Oregon and Washington]

Prickly Sow-thistle, Prickly Sow Thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle

Sonchus asper

Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper

Flower head of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper)

Prickly sow thistle as seen at Saddle Mountain in the Coast Range of northwestern Oregon.............June 14, 2009.

Prickly leaf of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper) - Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper)

Additional views of prickly sow thistle as seen at Saddle Mountain in the Coast Range of northwestern Oregon.......June 14, 2009.

Upper stem leaf of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper) - Flower head of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper)

Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper) - Involucral bracts of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper) - Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper)

Additional close-up photos of spiny sowthistle as seen along the Springwater Trail near Main City Park in Gresham, OR......September 15, 2010.

Close-up of the involucral bracts of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper) - Close-up of a stem leaf of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper) - Flower heads and upper stem leaves of Prickly Sow Thistle, Prickly Sow-thistle, Spiny Sowthistle, Spiny Sow-thistle, Spiny-leaf Sow-thistle: Sonchus asper (Synonyms: Sonchus asper ssp. asper, Sonchus asper ssp. glaucescens, Sonchus nymanii, Sonchus oleraceus var. asper)

Additional close-ups of the flower heads and stem leaves of prickly sow thistle as seen along the Springwater Trail between Gresham and Boring, Oregon........May 21, 2011. The lobes of the leaves which clasp the stem are somewhat rounded.

Paul Slichter