General: Stout perennial herb from a taproot; stems 1-3 m, glabrous, hollow, arising from erect, tuberous, chambered stem-base, often purplish and glaucous.
Leaves: Stem leaves compound with three major divisions that are in turn divided again; primary divisions bent back (not directed forward as in other similar species); leaf axis bent; leaflets reflexed, oblong to lanceolate, 4-10 cm long.
Flowers: Inflorescence terminal, of umbrella-like clusters; flowers white or pinkish; involucral bracts lacking.
Fruits: Rounded, 3-4 mm long, glabrous, with broadly winged lateral ribs.
1. Fruits strongly flattened, the lateral wings broadly winged; plants not essentially coastal.
2. Flowers yellowish; involucres present, leafy........................ A. dawsonii
2. Flowers white, greenish-white or sometimes pinkish; involucres lacking or rarely a few bracts present.
3. Main axis of the leaves bent, leaflets deflexed....................... A. genuflexa
3. Main axis of the leaves straight, leaflets not deflexed....................... A. arguta
Habitat / Range
Moist streambanks and open forests in the montane zone; common throughout BC, infrequent in the Queen Charlotte Islands and the adjacent coast; amphiberingian, N to AK, E to AB and S to N CA; E Asia.
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)
A shade-tolerant/intolerant, submontane to montane, Asian and Western North American forb distributed more in the Pacific than the Cordilleran region. Occurs in cool temperate and cool mesothermal climates on wet to very wet, nitrogen-rich soils (Moder and Mull humus forms): its occurrence decreases with increasing elevation and continentality. Common in open-canopy red alder, Sitka spruce, and western redcedar stands on water-collecting sites with gleysolic or organic soils. Often associated with Athyrium filix-femina and Lysichitum americanum. Inhabits depressions with a surface groundwater table. A nitrophytic species characteristic of nutrient-rich wetlands.
