Details about map content are available here Click on the map dots to view record details.
Introduction
Common dandelion is a familiar early spring flowering (February/March) perennial plant species in the daisy family (Asteraceae), which is typified by composite daisy-like flowers. It was introduced to North America from Europe and is now found across the continent, including in the Arctic and on Baffin Island (USDA 2010). In BC, it is found across most of the province in disturbed sites including lawns, roadsides, and pastures. In the spring, the species is distinctive with its cluster of bright yellow flowers and dark green elongated toothy leaves--flowers appear year-round and have mutiple petals and flowers. Plants have thick, long taproots. The earliest collection record for this species in the UBC Herbarium is a specimen collected by Eli Wilson in 1913, from Armstrong, BC. It was also collected in 1914 in Vancouver by J. K. Henry. This is the most widespread species of dandelion in North America, and it is now found worldwide (Brouillet 2010)
Species Information
Click on the image below to view an
expanded illustration for this species.
General: Perennial herb from a branched, stem-base and a thick, deep taproot; stems erect, solitary to several, simple, hollow, glabrous or sparsely long-hairy, exuding milky juice when broken, 5-60 cm tall.
Leaves: Basal leaves lanceolate to oblanceolate, 5-40 cm long, 1-10 cm wide, entire to toothed or more often pinnately lobed to pinnately cut or toothed, tapering basally to a more or less winged stalk, glabrous or slightly hairy; stem leaves lacking.
Flowers: Heads with strap-shaped flowers, solitary; involucres 15-25 mm tall; involucral bracts in 2 series, the outer ones lanceolate, reflexed, glabrous, the inner ones lanceolate, long-pointed; ray flowers yellow; disk flowers lacking.
Fruits: Achenes 3-4 mm long, not including the beak which is 2-4 times longer than the body, straw-coloured or greenish-brown to greyish, sharply ribbed and spiny above; pappus of numerous, 6-8 mm long, white hairlike bristles.
The genus Taraxacum has received widely varying treatments in North America. This is not unexpected in a group of plants in which hybridization, polyploidy, and apomixis are active. Some taxonomists (e.g., Ferris 1960, Weber 1967, Welsh 1974, Tayl. and MacBryde 1977, Douglas et al. 1989, Richards 1994, Cody 1996) recognize six or fewer native species (e.g., T. californium Munz. & Johnston, T. ceratophorum, T. eriophorum, T. lyratum, T. phymatocarpum and T. spectabile Dahlst.). Others have recognized 10 or more species (e.g., Fernald 1950, Hulten 1968, Scoggan 1979, Porsild and Cody 1980). The most conservative approach for our British Columbia species was taken by Boivin (1966-1967, 1972), Hulten (1968), Packer (1983) and Douglas (1989) who included T. eriophorum and T. lyratum within T. ceratophorum. Hulten (1968), however, included 45 "microspecies" under T. ceratophorum and still recognized nine other northern Taraxacum. I have recognized only one native Taraxacum species in British Columbia for several reasons. Of all the specimens I examined, only a small number would fit the description of the few species generally recognized. The remainder, when mature, represent an amazing array of variation that is often not repeated between sheets. In addition, most of the subalpine-alpine plants never set seed before the end of the short growing season, thus a key character, the achene, is often unavailable for determination. The time spent by several energetic Scandinavian taxonomists (e.g., G.A.H. Dahlstede, G. Haglund, and A.E. Porsild), formally naming several hundred "microspecies", has not enlightened the taxonomy of the genus. Even in recent years some taxonomists persist in naming every variation they encounter (e.g., Richards 1970). Until some brave taxonomist undertakes and successfully completes a thorough modern biosystematic study it would appear that the recognition of more than a single entity is not feasible.
The following identification key may be used to separate our species:
1. Native, non-aggressive, high elevation species (except rarely along roads in extreme northern British Columbia)..................T. ceratophorum
1. Introduced, aggressive weedy species of disturbed sites.
2. Achenes red to reddish-brown or reddish-purple at maturity, the beak mostly 1-2 (sometimes 3) times as long as the body; leaves mostly deeply cut for their entire length, without an enlarged terminal segment, the lobes narrow; outer involucral bracts appressed to loose or sometimes reflexed; inner involucral bracts usually horned at the tips............................T. laevigatum
2. Achenes olive- or straw-coloured to brown at maturity, the beak mostly 2.5-4 times as long as the body; leaves usually less deeply cut, often with an enlarged terminal lobe; outer involucral bracts reflexed, inner involucral bracts not horned at the tips...........................T. officinale
Source: Illustrated Flora of British Columbia
Habitat / Range
Mesic to dry roadsides, pastures, gardens and disturbed areas; common in S BC, less frequent northward; introduced from Europe.
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)
