Dandelion
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Dandelion (Taraxacum) is a large genus of flowering plants in the family Asteraceae. They are tap-rooted biennial or perennial herbaceous plants, native to temperate areas of the Northern Hemisphere and also temperate southern South America. The genus is taxonomically very complex, with numerous apomictic microspecies, and polyploidy is also common; over 250 species have been recorded in the British Isles alone (Richards 1972). Some botanists take a much broader viewpoint, and only accept a total of about 60 species.
The leaves are 5-25 cm long, simple and basal, entire or lobed, forming a rosette above the central taproot. As the leaves grow outward they push down the surrounding vegetation, such as grass in a lawn, killing the vegetation by cutting off the sunlight. A bright yellow flower head (which is open in the daytime but closes at night) is borne singly on a hollow stem (scape) which rises 4-30 cm above the leaves and exudes a milky sap ( latex) when broken. A rosette may produce several flowering stems at a time. The flower head is 2-5 cm in diameter and consists entirely of ray florets; it matures into a globe of fine filaments that are usually distributed by wind, carrying away the seed-containing achenes. This globe (receptacle) is called the "dandelion clock", and blowing it apart is a popular pastime for children. The number of blows required to completely rid the clock of its seeds is deemed to be the time of day. The flower head is surrounded by bracts (sometimes mistakenly called sepals) in two series. The inner bracts are erect until the seeds mature, then flex down to allow the seeds to disperse; the outer bracts are always reflexed downward. Some species drop the "parachute" (called a pappus, modified sepals) from the achenes. Between the pappus and the achene, there is a stalk called beak, which elongates as the fruit matures. The beak breaks off from the achene quite easily.
The name dandelion is a derivation of the Old French, dent-de-lion, literally "lion's tooth" on account of the sharply lobed leaves of the plant. In modern French the plant is called pissenlit, "urinate in bed", referring to its diuretic properties. Likewise, "pissabeds" is an English folkname for this plant and "piscialletto" in Italian.
- Species
- Taraxacum officinale (syn. T. vulgare), Common Dandelion. Found in many forms, but differs at least from the following species:
- Taraxacum albidum, a white-flowering Japanese dandelion.
- Taraxacum japonicum, Japanese dandelion. No ring of smallish, downward-turned leaves under the flowerhead.
- Taraxacum laevigatum (syn. T. erythrospermum), Red-seeded Dandelion; achenes reddish brown and leaves deeply cut throughout length. Inner bracts' tips are hooded.
- and others.
Dandelions are so similar to catsears (Hypochoeris) that catsears are also known as "false dandelions". Both plants carry similar flowers which form into windborne seeds. However, catsear flowering stems are forked and solid, whereas dandelions possess unforked stems that are hollow. Both plants have a rosette of leaves and a central taproot. However, the leaves of dandelions are jagged in appearance, whereas those of catsear are more lobe-shaped and hairy. Other plants with similar flowers include hawkweeds (Hieracium) and hawksbeards (Crepis); these are readily distinguished by their branched flowering stems.
Dandelions are used as food plants by the larvae of some species of Lepidoptera - see list of Lepidoptera which feed on Dandelions.
Cultivation and uses
Away from their native regions, they have become established in Australia and New Zealand as weeds. They are now common plants throughout all temperate regions.
While the dandelion is considered a weed by many gardeners, the plant does have several culinary and medicinal uses. Dandelions are grown commercially at a small scale as a leaf vegetable. The plant can be eaten cooked or raw in various forms, such as in soup or salad. They are probably closest in character to mustard greens. Usually the young leaves and unopened buds are eaten raw in salads, while older leaves are cooked. Raw leaves have a slightly bitter taste. Dandelion salad is often accompanied with hard boiled eggs.
Dandelion flowers can be used to make dandelion wine. The leaves are high in vitamin A, vitamin C and iron, containing more iron than spinach. Ground roasted dandelion root can be used as a coffee substitute. Drunk before meals, it is believed to stimulate digestive functions. Sold in most health food stores, often in a mixture, it is considered an excellent cleansing tonic for the liver.
Dandelion root is a registered drug in Canada, sold as a diuretic. A leaf decoction can be drunk to "purify the blood", for the treatment of anemia, jaundice, and also for nervousness. The milky latex has been used as a mosquito repellent; the milk is also applied to warts, helping get rid of them without damaging the surrounding skin. A dye can also be obtained from the roots of the plant. A new mixture of roasted roots is sold as a product called DandyBlend which tastes like coffee after the inulin in the dandelion is roasted.
" Dandelion and Burdock" is a soft drink that has long been popular in the United Kingdom, and authentic recipes are sold by health food shops, but it is not clear whether the cheaper supermarket versions actually contain either plant.