Mentzelia laevicaulis (Hook.) Torr. & A. Gray
blazing-star (blazing-star mentzelia; smoothstem blazingstar)
Loasaceae (Loasa family)

Introduction to Vascular Plants


© Thayne Tuason     (Photo ID #76376)


E-Flora BC Static Map

Distribution of Mentzelia laevicaulis
Click here to view the full interactive map and legend

Species Information

Biennial or short-lived perennial herb from a deep taproot; stems ascending to erect, several, branched, angular, harshly barbed-hairy throughout but nearly glabrous near the bases, 0.3-1 m tall.
Basal leaves linear to shallowly lobed, 10-15 cm long; stem leaves alternate, unstalked, oblong to egg-shaped but less deeply lobed.
Inflorescence of numerous flowers in a compact terminal or axillary cluster; petals 5, lemon yellow, 2.5-8 cm long; calyces 1-2.5 mm long; stamens 2/3 the length of the petals; bracts linear.
Capsules, oblong, 1.5-3.5 cm long; seeds numerous, flattened, winged, greyish-green or brownish.
Two, sometimes difficult to separate, varieties are recognized in BC:

1. Petals at least 4-8 cm long; fruits usually over 2 cm long ...................var. laevicaulis

1. Petals 1.5-4 cm long; fruits usually less than 2 cm long...................... var. parviflora (Dougl. ex Hook.) C.L. Hitchc.

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 Mentzelia laevicaulis

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)
597 411 784
Slope Gradient (%)
67 65 70

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

214 188 240
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
1 1 2
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(1), PP(1)

Habitat and Range

Dry slopes in the steppe and lower montane zones; frequent in SC BC; S to MT, UT and CA.

SourceThe Illustrated Flora of British Columbia