Lactuca biennis (Moench) Fernald
tall blue lettuce
Asteraceae (Aster family)
Introduction to Vascular Plants
tall blue lettuce
Asteraceae (Aster family)
Introduction to Vascular Plants
Species Information
General:
Annual or biennial herb from a taproot; stems erect, branched above, usually solitary, glabrous, exuding milky juice when broken, 0.6-2.5 m tall.
Leaves:
Basal leaves lacking; stem leaves alternate, pinnately cut or toothed, 10-40 cm long, 4-20 cm wide, sometimes hairy along the main veins, the upper ones with ear-like flanges at the base, clasping.
Flowers:
Heads with strap-shaped flowers, numerous in a narrow, elongate inflorescence; involucres 9-14 mm tall; involucral bracts lanceolate, graduated, often purplish at the tip, glabrous; ray flowers bluish to white, sometimes yellow, 13-34.
Fruits:
Achenes thin-edged, prominently nerved, beakless or shortly stout-beaked less than 1/2 the length of the body, 4-5.5 mm long; pappus brownish.
Illustration
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.
Illustration Source: The Illustrated Flora of British Columbia
Ecology
Ecological Framework for Lactuca biennis
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)
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 |
||
|
Avg |
Min |
Max |
|
| Elevation
(metres) |
244 | 44 | 555 |
| Slope
Gradient (%) |
10 | 0 | 76 |
|
Aspect (degrees) |
220 | 45 | 360 |
| Soil
Moisture Regime (SMR) [0 - very xeric; 4 - mesic; 8 - hydric] |
3 | 2 | 4 |
| Modal
Nutrient Regime
Class |
C | ||
| #
of field plots species was recorded in: |
30 | ||
| Modal
BEC Zone Class |
CWH | ||
|
All BEC Zones (# of stations/zone) species was recorded in |
CWH(26), SBS(1) | ||
|
Source:
Klinkenberg 2013
|
|||
Habitat and Range
Moist ditches, meadows and forest openings in the lowland, steppe and montane zones; frequent throughout most of BC; E to NF and S to NC, CO and CA.Status Information
Synonyms
Synonyms and Alternate Names:
Lactuca spicata auct. non (Lam.) Hitchc.
Lactuca spicata var. integrifolia (Torr. & A. Gray) Britton
Mulgedium spicatum auct. non (Lam.) Small
Mulgedium spicatum var. integrifolium (Torr. & A. Gray) Small