Petasites frigidus (L.) Fr. var. frigidus
sweet coltsfoot (arctic sweet coltsfoot)
Asteraceae (Aster family)

Introduction to Vascular Plants

Photograph

© Jamie Fenneman     (Photo ID #25445)


Map

E-Flora BC Static Map

Distribution of Petasites frigidus var. frigidus
Click here to view the full interactive map and legend

Species Information

General:
Perennial herb from a creeping root; stems erect, branched above, numerous, more or less white woolly-hairy, with parallel-veined bracts 2.5-6 cm long, reduced upwards, 5-50 cm tall, flowering stems appear before the leaves.
Leaves:
Basal leaves arising directly from the creeping root, triangular to heart-shaped on long stalks, shallowly to palmately lobed or toothed, white-woolly to nearly glabrous beneath, green and somewhat hairy above, 4-50 cm long; stem leaves alternate, reduced, represented by parallel-veined bracts 1-6 cm long, more or less white woolly-hairy.
Flowers:
Heads disciform or with ray and disk flowers, several to many in a round- to flat-topped inflorescence, stalks glandular and white-woolly; involucres 6-15 mm tall; involucral bracts oblanceolate to lanceolate, pointed, hairy basally with multicellular hairs, the crosswalls often purple, margins translucent, tips fine-hairy; ray flowers few, whitish or pinkish; disk flowers whitish.
Fruits:
Achenes 5-10-ribbed, glabrous, rarely sparsely long-hairy, 3-4.5 mm; pappus of numerous white, hairlike bristles.
Notes:
Three varieties occur in BC.

1. Leaves merely coarsely toothed or shallowly and obscurely lobed; plants of the subalpine and alpine zones........................ var. frigidus

1. Leaves conspicuously lobed; plants of the lowland to alpine zones.

2. Leaves palmately lobed and usually deeply cleft more than 1/2 way to the leaf base, usually broader than long; plants of the lowland and montane zones........................... var. palmatus (Ait.) Cronq.

2. Leaves lobed, sometimes palmately, but usually not cleft more than 1/2 way to the leaf base, usually longer than broad; plants of the subalpine and alpine zones...................... var. nivalis (Greene) Cronq.

SourceThe Illustrated Flora of British Columbia

Ecology

Ecological Framework for Petasites frigidus var. frigidus

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)
1375 679 2100
Slope Gradient (%)
6 0 50

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

63 30 358
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
5 3 7
Modal Nutrient Regime
Class
D
# of field plots
 species was recorded in:
27
Modal BEC Zone Class
MS

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

BAFA(2), BWBS(2), ESSF(2), ICH(2), IDF(1), IMA(1), MH(1), MS(9), SBPS(2), SBS(4), SWB(1)

Habitat and Range

Wet to moist ditches, streambanks, meadows and forests in the lowland to alpine zones; var. palmatus is common throughout all BC except the Queen Charlotte Islands and adjacent coast, var. nivalis is common throughout BC, and var. frigidus is frequent in extreme N BC and rare southward; var. palmatus - E to NF and S to MA, MI and CA; var. nivalis - E to PQ and N MN and S to N OR, and var. frigidus - circumboreal, N to AK, YT and NT, Eurasia.

SourceThe Illustrated Flora of British Columbia

Synonyms

Synonyms and Alternate Names:
Petasites alaskanus Rydb.
Petasites corymbosus (R. Br.) Rydb.
Petasites frigidus subsp. nivalis (Greene) Cody
Petasites frigidus var. corymbosus (R. Br.) Cronquist
Petasites frigidus var. hyperboreoides HultΘn
Petasites frigidus var. nivalis (Greene) Cronquist
Petasites gracilis Britt.
Petasites hyperboreus Rydb.
Petasites nivalis Greene