Taraxacum officinale |
Taraxacum palustre |
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common dandelion, dandelion, pissenlit officinal, red seed dandelion |
marsh dandelion, pissenlit palustre |
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Habit | Plants (1–)5–40(–60) cm; taproots seldom branched. | Plants 5–6.5(–10 in fruit) cm; taproots seldom branched. |
Stems | 1–10+, erect or ascending, sometimes ± purplish (usually equaling or surpassing leaves), glabrous or sparsely villous, slightly more so distally. |
1–5+, decumbent to ascending, purple, (rarely exceeding foliage before fruiting), sparsely villous or glabrate to ± densely villous distally. |
Leaves | 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). |
10+, horizontal to ± erect; petioles often purplish (midveins also), ± narrowly winged; blades oblanceolate to linear-oblanceolate, 2.5–9 × 0.2–1.1 cm, bases attenuate to long-cuneate, margins usually toothed, sometimes pinnately, shallowly lobed, lobes fewer than 10 per side, remote, (and teeth) straight to retrorse, narrow, deltate to narrowly triangular, often acuminate, apices obtuse to acute, faces glabrous or sparsely villous (particularly along midveins). |
Involucres | green to dark green or brownish green, tips dark gray or purplish, campanulate, 14–25 mm. |
green to grayish green, campanulate, 12–16 mm. |
Florets | 40–100+; corollas yellow (orange-yellow), 15–22 × 1.7–2 mm (outer). |
ca. 50; corollas yellow, outer abaxially gray-striped, 13–14 × 1.4–2.2 mm. |
Phyllaries | 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. |
14–16 in 2 series, lanceolate to lance-linear, 1.5–2.5 mm wide, margins scarious to narrowly scarious in proximal 1/2, apices long-acuminate, erose-scarious, hornless. |
Calyculi | 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. |
10–15, appressed to spreading, pale to dark purplish green, ovate to elliptic bracklets in 2 series, 6–8.5 × 2–5 mm, margins ± purplish, widely scarious, apices acuminate to caudate, hornless. |
Cypselae | 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. |
straw-colored to olivaceous, bodies narrowly obovoid, 2.8–4 mm, cones terete, 0.8–1 mm, beaks slender, 7–9 mm, ribs ca. 6, sharp, faces slightly muricate in distal 1/3; pappi white to cream, 4.5–6.5 mm. |
2n | = 24, 40, [16, 32]. |
= 24, 32, 40 (reported for complex in Europe). |
Taraxacum officinale |
Taraxacum palustre |
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Phenology | Flowering nearly year-round (fall–spring, south; spring or summer, north). | Flowering early spring. |
Habitat | Often damp low places, lawns, roadsides, waste grounds, disturbed banks and shores | Wet ditches, roadsides, and waste grounds of temperate climates |
Elevation | 0–2000+ m [0–6600+ ft] | 10–100 m [30–300 ft] |
Distribution |
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT; SPM; Greenland; Europe [Introduced in North America; also introduced in Mexico; introduced nearly worldwide]
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MI; NY; ON; QC; Europe [Introduced in North America] |
Discussion | 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.) |
This small dandelion has only recently been reported from North America (D. F. Brunton 1989). It has now spread east into Quebec, where it is known beyond the Montreal area, west into Michigan, and south into northern New York state. It is mostly spreading in wet ditches along highways and flowers in early spring. It clearly belongs to sect. Palustria. Until it is firmly associated with a European species, I am using the name Taraxacum palustre. The name T. cognatum Štepánek & Kirschner, which designates a microspecies from central Europe, has been applied to a North American specimen sent by D. F. Brunton to J. Kirschner. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 19, p. 244. | FNA vol. 19, p. 246. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Leontodon taraxacum, T. officinale var. palustre, T. sylvanicum | Leontodon palustris, T. turfosum |
Name authority | F. H. Wiggers: Prim. Fl. Holsat., 56. (1780) | (Lyons) Symons: Syn. Pl. Ins. Brit., 172. (1798) |
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