Lactuca serriola L.
prickly lettuce
Asteraceae (Aster family)

Introduction to Vascular Plants


© Paul Handford     (Photo ID #68697)


E-Flora BC Static Map

Distribution of Lactuca serriola
Click here to view the full interactive map and legend

Species Information

Biennial or winter annual herb from a fibrous root; stems erect, branched above, solitary, glabrous, exuding milky juice when broken, 0.3-1.5 m tall.
Basal leaves lacking; stem leaves alternate, prickly on the underside midrib, finely so on the margins, pinnately lobed or sometimes lobeless, twisted at the base to lie in a vertical plane, arrow-shaped, clasping, mostly 5-30 cm long, 1-10 cm wide.
Heads with strap-shaped flowers, numerous in a rounded inflorescence; involucres 10-16 mm tall; involucral bracts linear-lanceolate, irregularly graduated in 4 series; ray flowers yellow, often drying to blue, 13-47.
Achenes prominently nerved, grey or yellowish, 6-7 mm long with the slender beak 1-2 times as long as the body, compressed; pappus whitish.

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.


Ecological Framework for Lactuca serriola

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
752 213 1193
Slope Gradient (%)
27 0 70

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

226 26 356
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
3 0 8
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

BG(11), CWH(2), ICH(8), IDF(7), PP(7), SBS(1)

Habitat and Range

Dry roadsides, fields and waste places in the lowland, steppe and montane zones; common throughout S BC; introduced from Europe.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Lactuca scariola