Taraxacum officinale
Encyclopedia
Taraxacum officinale, the common dandelion (often simply called "dandelion"), is a herbaceous perennial plant
Perennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...

 of the family Asteraceae
Asteraceae
The Asteraceae or Compositae , is an exceedingly large and widespread family of vascular plants. The group has more than 22,750 currently accepted species, spread across 1620 genera and 12 subfamilies...

 (Compositae). It can be found growing in temperate regions of the world, in lawns, on roadsides, on disturbed banks and shores of water ways, and other areas with moist soils. T. officinale is considered a weedy species, especially in lawns and along roadsides, but it is sometimes used as a medical herb and in food preparation. As a nearly cosmopolitan weed, common dandelion is best known for its yellow flower heads that turn into round balls of silver tufted fruits that blow away on the wind.

Description

Taraxacum officinale grows from generally unbranched taproots and produces one to more than ten stems that are typically 5 to 40 cm tall but sometimes up to 70 cm tall. The stems can be tinted purplish, they are upright or lax, and produce flower heads that are held as tall or taller than the foliage. The foliage is upright growing or horizontally orientated, with leaves having narrowly winged petioles or being unwinged. The stems can be glabrous or are sparsely covered with short hairs. The 5–45 cm long and 1–10 cm wide leaves are oblanceolate, oblong, or obovate in shape with the bases gradually narrowing to the petiole. The leaf margins are typically shallowly lobed to deeply lobed and often lacerate or toothed with sharp or dull teeth. The calyculi (the cup like bracts that hold the florets) is composed of 12 to 18 segments: each segment is reflexed and sometimes glaucous. The lanceolate shaped bractlets are in 2 series with the apices acuminate in shape. The 14 to 25 mm wide involucres are green to dark green or brownish green with the tips dark gray or purplish. The florets number 40 to over 100 per head, having corollas that are yellow or orange-yellow in color. The fruits, which are called cypselae, range in color from olive-green or olive-brown to straw-colored to grayish, they are oblanceoloid in shape and 2 to 3 mm long with slender beaks. The fruits have 4 to 12 ribs that have sharp edges. The silky pappi
Pappus (flower structure)
The pappus is the modified calyx, the part of an individual disk, ray or ligule floret surrounding the base of the corolla, in flower heads of the plant family Asteraceae. The pappus may be composed of bristles , awns, scales, or may be absent. In some species, the pappus is too small to see...

, which form the parachutes, are white to silver-white in color and around 6 mm wide. Plants typically have 24 or 40 pairs of chromosomes but some plants have 16 or 32 chromosomes. Plants have milky sap and the leaves are all basal, each flowering stem lacks bracts and has one single flower head. The yellow flower heads lack receptacle bracts and all the flowers, which are called florets, are ligulate and bisexual. The fruits are mostly produced by apomixis
Apomixis
In botany, apomixis was defined by Winkler as replacement of the normal sexual reproduction by asexual reproduction, without fertilization. This definition notably does not mention meiosis...

. It blooms from March until October,

Taxonomy

The taxonomy of the genus Taraxacum
Taraxacum
Taraxacum is a large genus of flowering plants in the family Asteraceae. They are native to Eurasia and North America, and two species, T. officinale and T. erythrospermum, are found as weeds worldwide. Both species are edible in their entirety...

is complicated by apomictic and polyploid lineages, and the taxonomy and nomenclatural situation of Taraxacum officinale is not yet fully resolved, The taxonomy of this species has in the past been complicated by the recognition of numerous species, subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 and microspecies. E.g. Rothmaler's flora of Germany recognizes roughly 70 microspecies.
The plants introduced to North America are triploids that reproduce by obligate gametophytic apomixis Some authorities recognize three subspecies of Taraxacum officinale including:
  • Taraxacum officinale ssp. ceratophorum (Ledeb.) Schinz ex Thellung which is commonly called common dandelion, fleshy dandelion, horned dandelion or rough dandelion. It is native to Canada and the western US. Some sources list it as a species, Taraxacum ceratophorum.
  • Taraxacum officinale ssp. officinale, which is commonly called common dandelion or wandering dandelion.
  • Taraxacum officinale ssp. vulgare (Lam.) Schinz & R. Keller, which is commonly called common dandelion.


Two of them have been introduced and established in Alaska and the third (ssp. ceratophorum ) is native there.

Taraxacum officinale has historically had many English common names including: blowball, lion's-tooth, cankerwort, milk-witch, yellow-gowan, Irish daisy, monks-head, priest's-crown and puff-ball; other common names include, faceclock, pee-a-bed, wet-a-bed, canker-wort, and swine's snout.

Carl Linnaeus named the species Leontodon Taraxacum in 1753. The genus name Taraxacum, might be from the Arabic word "Tharakhchakon", or from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

 word "Tarraxos". The common name "dandelion," comes from the French
French language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

 phrase "dent de lion" which means "lion's tooth", in reference to the jagged shaped foliage.

Weeds

Taraxacum officinale is a common colonizer after fires, both from wind blown seeds and seed germination from the seed bank. The seeds remain viable in the seed bank for many years, with one study showing germination after nine years. This species is a somewhat prolific seed producer, with 54 to 172 seeds produced per head, and a single plant can produce more than 5,000 seeds a year. It is estimated that more than 97,000,000 seeds/hectare
Hectare
The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

 could be produced yearly by a dense stand of dandelions. When released, the seeds can be spread by the wind up to several hundred meters from their source, the seeds are also a common contaminate in crop and forage seeds. The plants are adaptable to most soils and the seeds are not dependent on cold temperatures before they will germinate but they need to be within the top 2.5 centimeters of soil.

Dandelion (Taraxacum officinale) has also been linked to outbreaks of stringhalt
Stringhalt
Stringhalt is a sudden flexion of one or both hind legs in the horse, most easily seen while the horse is walking or trotting. It is most evident when the horse is backing up slowly, turning on the affected leg, or suddenly frightened. It involves one or both hind limbs of the horse...

 in horses.

While not in bloom, this species is sometimes confused with others, such as: Chondrilla juncea
Chondrilla juncea
Chondrilla juncea is a species of flowering plant in the Aster family known by a number of common names, including rush skeletonweed, gum succory, devil's grass, and nakedweed...

, that have similar basal rosettes of foliage.

Distribution

Common dandelion is native to Eurasia, and now is naturalized throughout North America, southern Africa, South America, New Zealand, Australia, and India. It occurs in all 50 states of the USA and most Canadian provinces.

Uses

While the dandelion is considered a weed
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...

 by most gardeners and lawn owners, the plant has several culinary uses. The specific name officinalis refers to its value as a medicinal herb
Herb
Except in botanical usage, an herb is "any plant with leaves, seeds, or flowers used for flavoring, food, medicine, or perfume" or "a part of such a plant as used in cooking"...

, and is derived from the word opificina, later officina, meaning a workshop or pharmacy. The flowers are used to make dandelion wine, the greens are used in salads, the roots have been used to make a coffee-like drink and the plant was used by Native American
Native Americans in the United States
Native Americans in the United States are the indigenous peoples in North America within the boundaries of the present-day continental United States, parts of Alaska, and the island state of Hawaii. They are composed of numerous, distinct tribes, states, and ethnic groups, many of which survive as...

s as a food and medicine.
Dandelions are grown commercially on a small scale as a leaf vegetable
Leaf vegetable
Leaf vegetables, also called potherbs, green vegetables, greens, leafy greens or salad greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots...

. The leaves (called dandelion greens) can be eaten cooked or raw in various forms, such as in soup
Soup
Soup is a generally warm food that is made by combining ingredients such as meat and vegetables with stock, juice, water, or another liquid. Hot soups are additionally characterized by boiling solid ingredients in liquids in a pot until the flavors are extracted, forming a broth.Traditionally,...

 or salad
Salad
Salad is any of a wide variety of dishes, including vegetable salads; salads of pasta, legumes, eggs, or grains; mixed salads incorporating meat, poultry, or seafood; and fruit salads. They may include a mixture of cold and hot, often including raw vegetables or fruits.Green salads include leaf...

. They are probably closest in character to mustard
Mustard plant
Mustards are several plant species in the genera Brassica and Sinapis whose small mustard seeds are used as a spice and, by grinding and mixing them with water, vinegar or other liquids, are turned into the condiment known as mustard or prepared 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 egg
Egg (food)
Eggs are laid by females of many different species, including birds, reptiles, amphibians, and fish, and have probably been eaten by mankind for millennia. Bird and reptile eggs consist of a protective eggshell, albumen , and vitellus , contained within various thin membranes...

s. The leaves are high in vitamin A
Vitamin A
Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision...

, vitamin C
Vitamin C
Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...

 and iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

, carrying more iron and calcium
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...

 than spinach
Spinach
Spinach is an edible flowering plant in the family of Amaranthaceae. It is native to central and southwestern Asia. It is an annual plant , which grows to a height of up to 30 cm. Spinach may survive over winter in temperate regions...

.

Dandelion flowers can be used to make dandelion wine
Wine
Wine is an alcoholic beverage, made of fermented fruit juice, usually from grapes. The natural chemical balance of grapes lets them ferment without the addition of sugars, acids, enzymes, or other nutrients. Grape wine is produced by fermenting crushed grapes using various types of yeast. Yeast...

, for which there are many recipes. It has also been used in a saison
Saison
Saison is the name originally given to low-alcohol pale ales brewed seasonally in farmhouses in Wallonia, the French-speaking region of Belgium, for farm workers during harvest season...

 ale
Ale
Ale is a type of beer brewed from malted barley using a warm fermentation with a strain of brewers' yeast. The yeast will ferment the beer quickly, giving it a sweet, full bodied and fruity taste...

 called Pissenlit (literally "wet the bed" in French) made by Brasserie Fantôme
Brasserie Fantôme
Fantôme is a small brewery in Soy, Wallonia, Belgium. Founded in 1988 by Dany Prignon, it produces Saison, a type of farmhouse ale.-General:...

 in Belgium
Belgium
Belgium , officially the Kingdom of Belgium, is a federal state in Western Europe. It is a founding member of the European Union and hosts the EU's headquarters, and those of several other major international organisations such as NATO.Belgium is also a member of, or affiliated to, many...

. Another recipe using the plant is dandelion flower jam. Ground roasted dandelion root can be used as a coffee substitute
Coffee substitute
Coffee substitutes are non-coffee products, usually without caffeine, that are used to imitate coffee. Coffee substitutes can be used for medical, economic and religious reasons, or simply because coffee is not readily available. Roasted grain beverages are common substitutes for coffee.In World...

. In Silesia
Silesia
Silesia is a historical region of Central Europe located mostly in Poland, with smaller parts also in the Czech Republic, and Germany.Silesia is rich in mineral and natural resources, and includes several important industrial areas. Silesia's largest city and historical capital is Wrocław...

 and also other parts of Poland and world, dandelion flowers are used to make a honey substitute syrup
Syrup
In cooking, a syrup is a thick, viscous liquid consisting primarily of a solution of sugar in water, containing a large amount of dissolved sugars but showing little tendency to deposit crystals...

 with added lemon (so-called May-honey). This "honey" is believed to have a medicinal value, in particular against liver problems.

Dandelion root is a registered drug in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, sold principally as a diuretic
Diuretic
A diuretic provides a means of forced diuresis which elevates the rate of urination. There are several categories of diuretics. All diuretics increase the excretion of water from bodies, although each class does so in a distinct way.- Medical uses :...

. A leaf decoction
Decoction
Decoction is a method of extraction, by boiling, of dissolved chemicals, or herbal or plant material, which may include stems, roots, bark and rhizomes. Decoction involves first mashing, and then boiling in water to extract oils, volatile organic compounds, and other chemical substances...

 can be drunk to "purify the blood", for the treatment of anemia, jaundice, and also for nervousness. A hepatoprotective effect of chemicals extracted from dandelion root has been reported. Drunk before meals, dandelion root coffee is claimed to stimulate digestive functions and function as a liver tonic. "Dandelion and Burdock
Dandelion and burdock
Dandelion and burdock is a traditional British soft drink, drunk in the British Isles since about 1265. Traditionally it is made from fermented dandelion and burdock roots, and is naturally fizzy.- History :...

" is a soft drink that has long been popular in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 with authentic recipes sold by health food shops. It is unclear whether cheaper supermarket versions actually contain extracts of either plant.

The milky latex has been used as a mosquito repellent; the milk has also been used to treat warts, as a folk remedy.

Yellow or green dye colours can be obtained from the flowers but little colour can be obtained from the roots of the plant.

T. officinale is food for the caterpillar
Caterpillar
Caterpillars are the larval form of members of the order Lepidoptera . They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture...

s of several Lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...

 (butterflies and moth
Moth
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...

s), such as the tortrix moth Celypha rufana. See also List of Lepidoptera that feed on dandelions.

External links

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