Amaranthus albus

White pigweed ( Amaranthus albus)

The White pigweed ( Amaranthus albus), or White amaranth called, is a species of the genus Amaranthus ( Amaranthus ) within the family of Amaranthaceae ( Amaranthaceae ). He is originally from the central United States and large parts of North America and in Mexico are considered to be his home, in South America, Eurasia, Africa, and Australia, he is a neophyte.

• 8.1 Notes and references
• 8.2 Literature

Description

Appearance and leaf

The White Foxtail is a deciduous, annual herbaceous plant, reaching heights of growth of mostly 10 to 70, sometimes up to 100 centimeters. It is formed a taproot. The aboveground plant parts can be bald or hairy to glabrous sticky - fluffy. His most upright, sometimes ascending to rare low -lying, highly branched stems largely bald and hairy in the upper part more or less densely woolly, more or less green and white in the dried state. Large specimens form tumbleweeds.

The alternate on the stem arranged leaves are divided into petiole and leaf blade. The petiole of the cauline is about half as long as the leaf blade or about as long as the young pendent leaves with a length of 5 to 40 mm. Their simple leaf blade is at a length of 4-8 inches and a width of 1.5 to 3 centimeters elliptic to obovate or oblong - spatulate with stalk comprehensive, narrowly wedge-shaped Spreitenbasis and pointed to stumfem or curved and whitish to yellowish begranntem top end. The leaf margin is flat to more or less wavy, smooth, and sometimes he is cartilaginous and white. The stem leaves are obsolete and in their axils of new leaves develop. This pendant leaves have 7 to 20 mm long and 3-10 mm wide leaf blade. Sometimes the predominantly light green leaves are tinged with yellowish or reddish.

Inflorescence and flower

The flowering period extends into Central Europe from July to October and in California from June to October. The White Foxtail is monoecious getrenntgeschlechtig ( monoecious ). The green, green or yellowish - wießlich flower clusters are leaf axils. Female and male flowers are messed up in the flower clusters. The below each flower bracts are three and a half to twice as long as the perianth and lanceolate - linear to stachelspitzigen commended shaped with more or less pungent upper end at a length of 1.5 to 4 mm.

The inconspicuous, unisexual flowers are triple and green. Each flower contains only three green to brown, free bracts, which are significantly shorter than the bracts. Male flowers contain three free, fertile stamens. Female flowers contain three more or less equal, with a length of usually 1 to 1.5 ( 0.7 to 2 ) mm lanceolate -oblong to linealische, or narrow - ovate -free, thin bracts with pointed top and three durable, sedentary, erect, slender, papillary scarring. The egg-shaped, unilocular, Upper constant ovary contains only an erect ovule.

Fruit and seeds

The durable, ellipsoid - ovoid perianth enclosing the fruit and green-white to brown, and the lower part smooth during fruit ripening, above, especially near the upper end rugose - tuberculate. The fruit is ellipsoidal oval with a length of 1.5 to 2 mm. The pericarp ruptures at approximately half the height across with smooth edge on ( circumscissil ). Each fruit contains just one seed. The seeds are lens-shaped with a length of 0.8 to 1.1 mm. The seed coat is shiny reddish- brown to black and smooth.

Set of chromosomes

The basic chromosome number is x = 16; it lies in front of diploidy, ie 2n = 32

Confusion with other species

Especially when it comes to confusion herbarium of Amaranthus albus Amaranthus and blitoides. Both species are easily distinguished by the size and splendor of their seeds.

Ecology

The White Foxtail is a Therophyt. A copy developed up to about 100,000 seeds.

The flowers protogyn, which means the first female flower organs are capable of pollination and later scatter the male flower organs their pollen, but there is some overlap. This principle promotes cross-pollination, but it comes with this type usually to self-pollination. There is self- compatibility. Rarely Pollination is by wind.

Usually the seeds are the diasporas. Large specimens form tumbleweeds, also called steppe scooter; Winter tearing the whole plant above the ground and is further transported by the wind, the seeds are released and thus spread over wide areas.

The wind-pollinated flowers are not visited by many insects. Several species of insects feed on the leaves of Amaranthus species, for example, the beetle Disonycha triangularis, the caterpillars of Pholisora ​​catullus and some moth species. The seeds of Amaranthus species are eaten by some bird species, mainly those who are looking to open areas on base for food, especially in autumn and winter.

Occurrence

The natural range of the white fox tail are the central United States. It is naturalized in many areas of North America and in Mexico for a long time. InSüdamerika, Eurasia, Africa and Australia (New South Wales, Victoria and South Australia ), he is a neophyte.

The White Foxtail usually belongs to the ruderal vegetation. He settled in the climatically favored regions of Central Europe open sandy areas near villages, it grows along roads, on garbage dumps or old compost deposits, but also on railway ballast. He is said to have been introduced with grain from its North American home to Central Europe; speaks for its occurrence in the vicinity of loading facilities, in ports and rail yards. 1723 he first appeared in Tuscany. In Germany, the White Foxtail is naturalized since 1880. In Austria in this new citizen moderately frequent, otherwise scattered in the Pannonian region and lacking in Salzburg. In North America, the white fox tail thrives in disturbed habitats, fallow land, railway embankments, river banks, sandy sites, roadsides and in fields at altitudes 0-2200 meters.

In Central Europe, the White Foxtail thrives in "first year ruderal " class Sisymbrietea officinalis, such as crop inventories (excluding meadows, pastures, forests ), field Beikrautfluren (often short-lived due to crop rotation, by urgent) Association Violenea arvensis, or herb corridors, seams, herbaceous heaps outside the floodplains, ephemeral ruderal, salt herb corridors on urban-industrial special locations Salsolion Association, or river and meandering streams at lower elevations, one-year growth dried up river bank association Bidentetea tripartiti, it also occurs in association Eragrostion. The White Foxtail is Kennart Class Chenopodietea Br.-Bl. In 1951.

The White Foxtail need loose, slightly loamy or sandy, nutrient - and especially nitrate-rich soils, which should be fairly dry and the need to get very warm in the summer. Indicator values ​​according to Ellenberg are: light: 8 = half -light to full light plant, temperature: 8 = heat to extreme heat pointer Kontinentalitätszahl: 6 = temperate steppe climate pointing, moisture: 2 = strong drought to drought pointer, humidity change: no change of moisture showing reaction number: indifferent, nitrogen: 7 = nitrogen wealth showing salt: 1 = salt ertragend, but mostly no or low salt content showing heavy metal resistance: not resistant to heavy metal. Pointer values ​​for the civilization influence are after Kunick 1974 and Frank & Klotz 1988: human influence ( hemeroby ): 6 = polyhemerobic = very strong human influence, binding to cities ( urban ): = Urbanophil bound to cities.

System

The first publication of Amaranthus albus was made in 1759 by Carl Linnaeus in Systema Naturae, Editio Decima 2, p in 1268. Homonyms for Amaranthus albus Amaranthus albus L. are Thunb. (published in Flora Capensis, 2nd edition, 1823, p 215) and Amaranthus albus Rodschied ex F. Dietr. (published in Complete Lexicon of gardening and botany, 2nd edition, 1, 1824, p 196). Amaranthus albus L. Synonyms for are: Amaranthus albus var pubescens ( Uline & WLBray ) Fernald, Amaranthus gracilentus HWKung, Amaranthus pubescens ( Uline & WLBray ) Rydb. The specific epithet albus meaning white.

Amaranthus albus belongs to the subgenus of the genus Amaranthus Albersia within the family Amaranthaceae.

Use

The leaves and young aerial parts of Amaranthus albus cooked taste mild. They are rich in vitamins and minerals and can be eaten like spinach. The seeds are eaten raw or cooked. The seeds are ground into flour and baked bread from it. The fiddly with a diameter of about 1 mm in size are very nutritious. If the seeds are cooked as a whole siey gelatinous, but it is difficult to chew all the small seeds in the mouth and so they pass through the digestive system undigested ( dietary fiber).

It is yellow and green with the plant parts of Amaranthus albus.

Trivial names

Trivial names are other languages: in French and Italian Amaranto Amarante blanche bianco.

Swell

• Sergei L. & Kenneth R. Robertson Mosyakin: Amaranthus: Amaranthus albus, S. 413 - the same text online as well as printed work, In: Flora of North America Editorial Committee ( eds.): Flora of North America North of Mexico, Volume 4 - Magnoliophyta: Caryophyllidae, part 1 Oxford University Press, New York and Oxford, 2003, ISBN 0-19-517389-9 ( Description section ).
• Mihai Costea, 2012: Data sheet at Jepson eFlora. ( Description section )