The Common Dandelion is an introduced and naturalized perennial forb that grows with erect to ascending stems from 2 to 12 inches high. Flowering stems (technically scapes) are round, green, sometimes with purplish coloration, are smooth and contain a milky juice. A plant typically produces 1 to 10 stems.
The leaves are all basal forming a rosette and can number as many as 20+ on a robust plant. They are oblong to spatulate in shape, held horizontally to erect, long and pinnately divided into shallow-to-deep lobes with the terminal lobe usually larger or as large as the nearest two lateral lobes. Lobes usually have teeth which become very small and pointed on the lobes near the leaf tips. Leaf stalks usually have narrow wings. The prominent main vein of the leaf is hollow, like the scape and has the same milky juice. It appears depressed on the upper surface and very prominent on the underside. The leaf underside is slightly paler in color with some fine soft hair. Large leaves can show considerable variation in lobe arrangement.
The floral array consists of a single one to two inch wide flower head at the top of each scape.
The flower head consists of 40 to 100+ ray florets with yellow to orange-yellow corollas and rays. These florets open from the outer edge toward the center. The anthers of the five stamens are usually also yellowish and the styles, which have a forked tip, are yellow to brownish. The flower head has two groups of floral bracts (phyllaries and calyculi). The inner group -the phyllaries - number 13 to 18, are in two series, are linear in shape with pointed tips. They are appressed to the base of the florets forming a cup around the ovaries and remain that way until the head turns to seed. The outer group of calyculi number 12 to 18, are in two series, lanceolate in shape, dark pointed tips, usually with hairy margins, and reflexed during flowering and seed production.
Seed: When fertility is accomplished, the inner group of phyllaries close up, resembling the original flower bud, until the seeds are mature. Then they re-open, reflexing backward, when the seeds are mature. These are a dry grayish-green to olive-brown ribbed cypsela, spindle shaped at one end and narrowed to a long beak at the other, the beak being 2 to 3x the length of the cypsela; this beak supports a fluffy white pappus. The ribs number 4 to 12 and are sharply pointed. The seed head is then a gossamer ball in shape and seeds are distributed by the wind.
Habitat: Common Dandelion grows from a stout fleshy taproot. The plant does not spread vegetatively but instead by seed dispersal. Late germinating seeds will form a rosette only the first year. The prolific nature of seed production leads this plant to be found in most areas that are not cultivated. It adapts to most soils, does best in full sun with moist to dry conditions.
Names: The genus Taraxacum is the Medieval name for the Dandelion, believed to be derived from the Arabic and then to the Persian words talkh chakok, referring to a bitter herb. Mrs. Grieve (Ref.#7) lists several alternatives, one being the derivation from the Greek taraxos, for 'disorder' and akos, for remedy, together referring to the curative action of the plant. The species name, officinale, means 'sold in shops' and refers to the former availability of the plant in places that provided herbal medicines. The author name for the plant classification, ‘F.H.Wigg.’ refers to Friedrich Heinrich Wiggers, (1746-1811) German botanist whose prime work was about the flora of Holstein - Florae Primitiae holsatica. The common name of Dandelion is often said to be from the resemblance of the leaf margins to the jaw of a lion and its teeth as this sort of reference was made in several old herbals.
Comparisons: The two most look-a-like species of Taraxacum are T. erythrospermum, the Red-seeded Dandelion, and T. lapponicum, the Lapland Dandelion. However in both the cypselae are reddish to reddish-brown. Additionally T. lapponicum is found only in boreal to low Arctic areas.
Above: Each flower head can have 40 to 100+ ray florets. The styles are a darker color and have a forked tip, extending above the rays. The underside of the head has a series of floral bracts spreading outward under the rays (the phyllaries) while an outer group (the calyculi) reflexes backward when the flower opens.
Below: Small plants will have only one scape (the flowering stem). Leaves are all basal, forming a rosette. The upper section of the leaf usually has a larger terminal lobe with very fine teeth as shown here while the leaf underside is paler in color due to very fine hair. Note the main vein is depressed on the upper surface and protruding on the underside.
Above: Leaf appearances can very greatly. The very large leaf shown here has a slightly different terminal lode than the one shown up above. The lobes all have teeth of varying sizes and the the leaf tapers to a slight wing on the stalk.
Below: Robust plants can produce a number of scapes simultaneously with additional buds forming.
Below: When the flower head matures the inner ring of phyllaries also reflex allowing the seed head to open. The olive to brown achenes have a long beak with pappus attached. The upper section of the ribbed cypsela has a series of very pointed teeth on the ribs. Drawing courtesy of Kurt Stüber's Online Library.
Below: The gossamer ball shaped seed head of the plant. The second photo (©Dan Tenaglia) is a comparison of the seeds of Red-seeded Dandelion, T. erythrospermum.
Below: 1st photo - The seeds are spindle shaped with sharp ribs tapering abruptly to a long thin beak, several times longer than the cypsela itself. 2nd photo - The deep root system is deep and most of the root must be removed to prevent the plant from re-sprouting.
Below: To some, a field of blooming dandelion is a splendid sight; to the urban lawn guru it is considered an abomination and has started more than one dispute among otherwise agreeable neighbors. However, in Spring when the pollinators are first active, the Dandelion is one of the few sources of nectar for them to build up their reserves after the long winter, thus some should be left for them until other sources are available.
Common Dandelion is considered indigenous to the Garden especially since it is almost impossible to not have the plant show up when there are adjacent populations. Eloise Butler noted its presence on May 25, 1907. Common Dandelion originally was brought from Europe and is now distributed across all of North America. According to DNR surveys both T. erythrospermum and T. officinale are found in Minnesota with T. officinale most widely distributed - most counties not reporting it are clustered in the SW quadrant of the state whereas T. erythrospermum if known in only 24 widely scattered counties, some in the metro area, but not Hennepin..
Uses- medicinal and practical: Members of the Taraxacum have been used for some time medicinally as a diuretic and in household food supplies as greens and in the making of Dandelion Wine (Mrs. Grieve -Ref.#7 - gives a recipe). The plant is a rich source of Vitamin C. For use as a salad herb, the herby taste of older leaves is dispelled by covering the leaves with boiling water, not cold water, then served cold with a dressing. Some say young leaves are fine as-is. Coffee (or some will say - a palatable bitter drink) or a substance to adulterate coffee, can be made from the dried ground roots. Dandelion beer was a fermented drink, cheaper and less intoxicating that grain beers, made from the leaves whereas the wine is made from the flowers. The root contains a stronger juice than the stems and medicinal uses of the root are recorded back to the early Arabian physicians of the 10 and 11th centuries. Mrs. Grieve (Ref. #7) has an extensive text on Dandelion.
Nicolas Culpepper (Ref. #4b ) noted in 1652 that: "It is of an opening and cleansing quality . . . it openeth the passages of the urine both in young and old [which led to the name used by country people - 'Piss-a-bed']. And whoever is drawing towards a consumption, or an evil disposition of the whole body, called, by the use hereof for some time together, shall find a wonderful help. It helpeth also to procure rest and sleep to bodies distempered by the heat of the ague-fits, or otherwise: The distilled water is effectual to drink in pestilential fevers, and to wash the sores. You see here what virtues this common herb hath, and that is the reason the French and Dutch so often eat them in the Spring: and now, if you look a little farther, you may plainly, without a pair of spectacles, that foreign physicians are not so selfish as ours are, but more communicative of the virtues of plants to people."
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"