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.
- 
Additional views of prickly sow thistle as seen at Saddle Mountain in the Coast Range of northwestern Oregon.............June 14, 2009.
Prickly sow thistle growing along lower Arizona Creek at the eastern edge of the Pueblo Mountains of southeastern Oregon................June 1, 2012.
- 
- 
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