General: Deciduous perennial herb from a slender rhizome, spreading; aerial stems absent but single leaves are sent up along the rhizome.
Leaves: Basal, palmately compound with 3 leaflets, blades fan-shaped, 3-9 lobed, deciduous, with a vanilla-like fragrance when dry.
Flowers: Inflorescence in compact spikes, 2-5 cm long; sepals and petals lacking; stamens white, 8-20 mm long.
Fruits: Achenes dark brown to reddish-purple, 3-4 mm long, finely hairy, with a somewhat fleshy to leathery thickened ridge.
Notes: Recently some taxonomists (e.g., Williams 1993, Kartesz 1994) have recognized a second species (A. californica) in western North America. The latter is characterized by having a central leaflet with 6-8 lobes, whereas A. triphylla has a central leaflet with 3 lobes. Examination of herbaria material reveals that many sheets have mixed collections of plants with central leaflets with both 3 lobes (actually the 3-lobed ones usually have 2 additional, much smaller lobes, on the sides) and 7-9 lobes. This has also been noted in the field. At this time, we are not convinced that A. californica is worthy of recognition.
Moist to mesic open or closed forests in the lowland and montane zones; frequent in SW BC; known from Vancouver Island, the Gulf Islands and the adjacent lower mainland; S to NW CA.
According to Brayshaw (1989), this species in North America consists of two types with different chromosome numbers. One is diploid (2n=12) and "occupies well-drained, often open upland sites. The other [type] is tetraploid (2n=24)...and tends to occupy deeply shaded sites on low bottomland forests". While there are morphological differences, Brayshaw indicates that the important separating characters--stomatal size-- are not easily visible and require a microscope for examination.
Note author: R. Klinkenberg July 17, 2009.
Similar Species
According to Brayshaw (1989), this species in North America consists of two types with different chromosome numbers. One is diploid (2n=12) and "occupies well-drained, often open upland sites. The other [type] is tetraploid (2n=24)...and tends to occupy deeply shaded sites on low bottomland forests". While there are morphological differences, Brayshaw indicates that the important separating characters--stomatal size-- are not easily visible and require a microscope for examination.
Note author: R. Klinkenberg July 17, 2009.
Ecology
Ecological Framework for Achlys triphylla
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, submontane to montane Western North American forb distributed more in the Pacific than the Cordilleran region. Occurs in maritime to submaritime cool mesothermal climates on nitrogen-rich soils. Its occurrence decreases with increasing latitude, elevation, and continentality; plentiful on Vancouver Island, sparse on coastal mainland. Most frequent on water-shedding and water-receiving sites; commonly associated with Polystichum munitum. Characteristic of Moder and Mull humus forms.
