Sonchus asper (L.) Hill ssp. asper

Family: Asteraceae, Tribe: Cicharieae

Pertinent Synonyms & Notes (particularly those used in California; go to GRIN for other synonyms)

Sonchus oleraceus L. var. asper L.

Pertinent Common Names (particularly those used in California; go to GRIN for other common names)

spiny sowthistle

Primary Disseminule Type


Description (diagnostics are in brown)

Fruit a cypsela, elliptic to oblanceolate, sometimes slightly curved and/or twisted, strongly compressed, cross-section narrowly elliptic, 2–3 mm long x 1–1.6 mm wide x 0.1–0.3 mm thick. Surface straw-colored to reddish-brown, dull to faintly glistening, longitudinally ribbed (typically 3 ribs on each face plus the 2 ribs on the edges). Pappus ± persistent, bristles 6–9 mm long (ca. 3 times the length of the fruit body), numerous, fine, often entangled around fruit, white.

Style base inconspicuous, apical scar (when pappus is removed) ± raised, 0.15–0.25 mm across.

Fruit attachment scar basal, a polygonal (4-segmented) cup-like extension of the fruit with cream-colored rim and cavity.

Similar Species

Similar Species Comparison Chart

Risk Assessment (codes in yellow or red indicate cause for concern; assessments are current as of mid-2011; click AUQP, NZBORIC, or NZBPI for access to the most recent versions of these databases and possible assessment changes)