2. Taraxacum officinale F.H. Wigg. (common dandelion)
T. vulgare Schrank (an illegitimate name)
Pl. 263 b, c;
Map 1100
Stems 2–40 cm
long. Leaves (3–)8–45 cm long, variably shallowly to very deeply lobed (nearly
compound), sometimes more shallowly lobed toward the tip than toward the base.
Involucre 12–25 mm long, the inner series of bracts mostly 13–23, the outer
series less than to more than half to about half as long as the inner series.
Fruits with the body 3–4 mm long, olive-colored to greenish brown at maturity.
2n=16, 18, 22, 24, 26, 32, 33, 37, 46, 47, 48. January–December.
Introduced,
common throughout the state (native of Europe, introduced nearly worldwide).
Banks of streams and rivers, ledges of bluffs; also lawns, gardens, cemeteries,
crop fields, fallow fields, pastures, roadsides, railroads, and open, disturbed
areas.
The name T.
officinale was lectotypified by Richards (1985) to refer to a very
different species, a Scandinavian endemic that is only distantly related to the
widespread, weedy taxon found in North America. Unfortunately, it is unclear
which of the nearly 50 species names in sect. Ruderalia (Kirschner and
Štěpánek, 1987) should be used for the introduced North American plants,
which represent presumed multiple introductions from different Old World sources.
The present treatment uses the traditional nomenclature for the common
dandelion as broadly circumscribed, until further study clarifies the
situation.
Dandelions
flowering in lawns are both welcomed by urbanites as a sign of spring and
cursed by homeowners, who have helped to fuel the herbicide and lawn care
industries through their desire to produce the unblemished great American lawn.
However, dandelions also are becoming popular as a “field green” among gourmets
and are slowly expanding from a familiar weed to a minor organic crop in
portions of the northern United States. The leaves are highly nutritious and
are a good source of various vitamins and iron. They are frequently sold in
mesclun salad mixtures, which contain several fancy lettuce cultivars as well
as leafy greens from various species of Brassicaceae, Chenopodiaceae, and
Asteraceae (Ryder, 2002). Care should be taken that any plants harvested from
nature be from areas free of pesticide residues. In addition to its use in
salads, the flowering heads or more commonly just the corollas are mixed with
sugar and various flavorings, then allowed to ferment, to produce the alcoholic
beverage known as dandelion wine. The roots occasionally have been used as a
chicory substitute and are also a source of the sugar substitute inulin (see
the treatment of Cichorium for more information). In Europe, the plants
have a history of medicinal use as a laxative, diuretic, and tonic and were
also used “to cleanse the blood” (for liver ailments).