Practical ecological knowledge for the temperate reader.

Petasites Sp. - Coltsfoot

Family: Asteracea - Sunflowers

"Perennial herb from stout rhizome; ± dioecious. Stem: erect, unbranched, often appearing before basal leaves. Leaf: basal large, long-petioled, blades wide, entire, toothed, or ± palmately lobed; cauline generally sheathing, scale-like, proximal sometimes with blades. Inflorescence: heads generally disciform or weakly radiate, sometimes discoid, in raceme-like to ± umbel-like clusters; involucre ± cylindric to bell-shaped; main phyllaries in 1 series, equal; receptacle flat to convex, epaleate. Pistillate flower: 0–20(70) (sterile) in staminate heads, (1)30–130+ in pistillate heads; corollas of 2 kinds, white to pale yellow, sometimes ± purple, outer often with short ray, inner cylindric. Disk flower: generally staminate (rarely bisexual), 0–12 at center of pistillate heads, 11–78 in staminate heads; corolla white to pale yellow, sometimes ± purple; anther base entire or short-sagittate, tips acute; style tips slightly thickened, entire or slightly lobed; pappus reduced. Fruit: cylindric, 5–10-ribbed; pappus bristles 60–100+.
15–18 species: North America, Eurasia. (Greek: broad-brimmed hat, from large leaves) " [Jepson]

Local Species;

  1. Petasites frigidus [E-flora] - Sweet coltsfoot &
  2. Petasites japonicus - Japanese butterbur [E-flora][PCBC]

Species Mentioned;

Petasites & Tussilago sp., P. sagittatus, P. hyperboreus, P. frigidus, P. palmatus, P. japonicus.[Schofield]


Though coltsfoot is generally regarded as quite safe in moderation, it is not recommended for extended use in high dosages. Like comfrey, the plant contains pyrrolizidine alkaloids that can irritate the liver, causing lesions if taken in excess. Large amounts of coltsfoot tea may spark abortion. [Schofield]

Edible Uses

"... prepares coltsfoot for tea-making by drying the herb, and then whizzing it in a blender. The felty leaf backing balls up and can easily be discarded. Large summer leaves are placed on top of vegetable kegs to prevent mold."[Schofield]

Other Uses

Medicinal Uses

Petasites frigidus - Sweet Coltsfoot

Family: Asteraceae (Aster family)[E-flora-2]

Other Names: arctic sweet coltsfoot)[E-flora-2]




"Four varieties of this species are presently recognized in British Columbia: var. frigidus, var.nivalis, var. palmatus, and var. sagittatus. Petasites frigidus var. sagittatus is recognized at the variety level, however, it was previously recognized at the species level in the Illustrated Flora of British Columbia. This differs from the current presentation in the Flora of North America. However, the species taxonomy will be reassessed by the BC Conservation Data Centre shortly. The map on this species page reflects specimens in collections not identified to the sub-taxa level." [E-flora-2]

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." [IFBC-E-flora-2]

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." [IFBC-E-flora-2]

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." [IFBC-E-flora-2]

Fruits: "Achenes 5-10-ribbed, glabrous, rarely sparsely long-hairy, 3-4.5 mm; pappus of numerous white, hairlike bristles." [IFBC-E-flora-2]


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. [IFBC-E-flora-2]

Habitat / 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." [IFBC-E-flora-2]

Origin Status: Native [E-flora-2]

Ecological Indicator Information

"A very shade­intolerant, montane to alpine, circumpolar forbs distributed in Pacific, Cordilleran, and Central North America. Species occurs on very moist to wet, nitrogen-rich soils within alpine tundra and sub­alpine boreal climates. Frequent in non-forested communities, and in open-canopy forests, common on floodplains and on exposed mineral soil at roadsides and landslides. Occasional in nutrient-rich wetlands"

Edible Uses