Taraxacum officinale
Taraxacum lapponicum
common dandelion, dandelion, pissenlit officinal, red seed dandelion
Lapland dandelion, pissenlit de laponie
1–10+, erect or ascending, sometimes ± purplish (usually equaling or surpassing leaves), glabrous or sparsely villous, slightly more so distally.
1–5, erect to ascending, purplish, (usually exceeding leaves), glabrate to sparsely villous proximally, ± densely villous distally.
20+, horizontal to erect;
petioles ± narrowly winged;
blades oblanceolate, oblong, or obovate (often runcinate), (4–)5–45 × (0.7–)1–10 cm, bases attenuate to narrowly cuneate, margins usually shallowly to deeply lobed to lacerate or toothed, lobes retrorse, broadly to narrowly triangular to nearly lanceolate, acute to long-acuminate, terminals ± as large as distal laterals, ultimate margins toothed or entire (secondary lobules irregular, perpendicular to retrorse), teeth minute to pronounced apices acute to acuminate or obtuse, faces glabrous or sparsely villous (commonly on midveins).
5–20, erect to patent, sometimes horizontal;
sessile (bases sometimes as wide as blade) to ± broadly winged petiolate (occasionally slender on young or deeply shaded specimens, usually at least some ± winged);
blades oblanceolate or oblong-oblanceolate (often runcinate), (3–)3.5–27 × 0.6–5 cm, bases usually cuneate, sometimes attenuate, margins regularly and shallowly lobed, sometimes ± deeply (not lacerate) to dentate, lobes mostly retrorse, usually triangular, sometimes deltate or lanceolate, ± acuminate, often replaced by teeth, teeth 0–5 on lobes or irregular, often coarse, triangular to lanceolate, ± acuminate, apices obtuse or acute to short-acuminate, faces glabrous or glabrate, midveins often sparsely villous.
green to dark green or brownish green, tips dark gray or purplish, campanulate, 14–25 mm.
green to dark green, campanulate to cylindro-campanulate, 12–22 mm.
40–100+;
corollas yellow (orange-yellow), 15–22 × 1.7–2 mm (outer).
60–110+;
corollas yellow (outer abaxially gray and/or purplish striped), 15–22 × 1.1–1.7 mm.
13–18 in 2 series, lanceolate, 2–2.8 mm wide, margins scarious (proximal 2/3) to narrowly scarious, apices acuminate, erose-scarious, usually hornless (seldom appendaged), callous.
14–18 in 2 series, lanceolate, 1.4–3.2 mm wide, margins not or very narrowly scarious (outer) to narrowly scarious in proximal 1/2 (inner), apices long-acuminate, hornless, tips ± hyaline, blackish and/or purplish, scarious.
of 12–18, reflexed, sometimes ± glaucous, lanceolate bractlets in 2 series, 6–12 × 2.8–3.5 mm, margins very narrowly white-scarious, sometimes villous-ciliate distally, apices acuminate, hornless.
of 10–12, spreading to eventually reflexed, often pale, sometimes purplish-tinged, lance-ovate to broadly lanceolate (thin) bractlets in 3 series, 5.5–9.5 × 1.8–2.7(–4.2) mm, margins not or narrowly scarious, apices long-acuminate, hornless.
olivaceous or olive-brown, or straw-colored to grayish, bodies oblanceoloid, (2–)2.5–2.8(–4) mm, cones shortly terete, 0.5–0.9 mm, beaks slender, 7–9 mm, ribs 4–12, sharp, faces proximally smooth to ± tuberculate, muricate in distal 1/3;
pappi white to sordid, 5–6(–8) mm.
tan to reddish brown, bodies oblanceoloid, 2.8–3.5 mm, cones conic, 0.5–0.8 mm, beaks slender, 6.5–12 mm, ribs 4–5 prominent (to 13–15 fine), faces proximally smooth to occasionally slightly tuberculate, muricate in distal 1/4–1/3 (spines usually sparse);
pappi white to cream, 5–7.5 mm.
= 24, 40, [16, 32].
= 32.
Taraxacum officinale
Taraxacum lapponicum
Taraxacum officinale is the most widespread dandelion in temperate North America, though its abundance decreases in the arid south. It is a familiar weed of lawns and roadsides. It is also the species most commonly used for medicinal and culinary purposes (e.g., E. Small and P. M. Catling 1999).
Phenotypic and genotypic variation of this species have been studied in North America (L. M. King 1993; King and B. A. Schaal 1990; J. C. Lyman and N. C. Ellstrand 1998; O. T. Solbrig 1971; R. J. Taylor 1987), but results of those studies did not lead to the recognition of microspecies.
Specimens of Taraxacum officinale with deeply lobed leaves are sometimes difficult to distinguish from those of T. erythrospermum when fruits are missing (see also R. J. Taylor 1987). Usually, however, early leaves of the former are much less deeply lobed than those of the latter, which are more consistently lacerate throughout development, though broadly winged initially. The two taxa are easily distinguished in fruit, the red cypselae of T. erythrospermum standing out from the dull olive ones of T. officinale.
In northeastern North America, Taraxacum officinale and T. lapponicum often are confused, which has led to reports of the common dandelion farther north than I have been able to verify (it has yet to be collected from the Nunavik region of Quebec, for instance). The characters in the key above help separate the two taxa.
The typification by A. J. Richards (1985) would leave the common dandelion of both Europe and North America without a valid name (J. Kirschner and J. Štepánek 1987). For the time being, with the nomenclatural situation still not resolved, I am following traditional usage of the name Taraxacum officinale.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Taraxacum lapponicum is an amphi-Atlantic taxon whose North American distribution lies in the eastern Arctic and boreal zones.
This species has the most controversial taxonomy. Barely distinguishable morphotypes have received species names, and the phenotypic plasticity of the taxon has not been taken into account in that process. In particular, it is often found in more shaded habitats than other dandelions in the south of its range, particularly when growing along streams in eastern Canada. The correct name to be applied to this species is controversial, and many European names have been applied to North American plants in the complex, sometimes without regard to the type. Here, I am recognizing a more widely defined species, using the name Taraxacum lapponicum, the one most often used in North America (correctly or not), pending more rigorous experimental study of variation in the complex.
The name Taraxacum islandiciforme Dahlstedt ex M. P. Chistiansen is invalid.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
LA Plants, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria, 
SW CO Wildflowers, Turner Photog. 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
