[Introduced Lettuce: The Genus Lactuca East of the Cascade Mountains of Oregon and Washington]

Prickly Lettuce

Lactuca serriola

Synonyms: Lactuca scariola, Lactuca scariola var. integrata, Lactuca scariola var. scariola

Prickly Lettuce: Lactuca serriola (Synonyms: Lactuca scariola, Lactuca scariola var. integrata, Lactuca scariola var. scariola)

Prickly lettuce on the side of Forest Service Road 16 east of Big Creek in Logan Valley, Malheur National Forest..........August 20, 2011.

Flower head of Prickly Lettuce: Lactuca serriola (Synonyms: Lactuca scariola, Lactuca scariola var. integrata, Lactuca scariola var. scariola) - Involucral bracts of Prickly Lettuce: Lactuca serriola (Synonyms: Lactuca scariola, Lactuca scariola var. integrata, Lactuca scariola var. scariola)

Prickly leaves of Prickly Lettuce: Lactuca serriola (Synonyms: Lactuca scariola, Lactuca scariola var. integrata, Lactuca scariola var. scariola)

Additional close-ups (from left to right) of the flower head, overlapping involucral bracts, and prickly, lobed leaves of prickly lettuce on the side of Forest Service Road 16 east of Big Creek in Logan Valley, Malheur National Forest...........August 20, 2011.
Paul Slichter