Knotweed

Knotweed
	Knotweed ( Fallopia convolvulus )
Systematics
	Nuclear eudicotyledons
Order :	Clove-like (Caryophyllales)
Family :	Knotweed family (Polygonaceae)
Subfamily :	Polygonoideae
Genre :	Winged knotweed ( fallopia )
Type :	Knotweed
Scientific name
	Fallopia convolvulus
	( L. ) Á.Löve

The knotweed or field knotweed ( Fallopia convolvulus (L.) A. Löve , syn .: Polygonum convolvulus L. ) is a species of knotweed ( Fallopia ) in the knotweed family (Polygonaceae). The EPPO code is POLCO. It is considered an annual "field weed" that germinates mainly in spring.

Stems with flowers and fruits with fruit perigone

The perigone is densely dotted with glands. The outer tepals are keeled, but do not run down the fruit stalk. This is structured above the middle.

Knotweed ( Fallopia convolvulus )

The stem is angular and rough due to the downwardly directed chin-up hooks.

The fruits are grainy to finely striped lengthways and matt.

description

It is an annual herbaceous plant that grows crawling or climbing with a stalk over a meter long. The stem is angular and rough, at least in the lower area. The species is a right winder like the knotweed . It has roots up to 80 centimeters deep.

The cotyledons of the knotweed are three or more times as long as they are wide. The leaf halves are mostly unequal. The leaves are heart-shaped and inclined downward in the shape of an arrow towards the tip, in contrast to Convolvulus arvensis . In addition, the leaves are stalked and the leaf veins are clearly visible.

The flowers of the knotweed are white-green and inconspicuous. They stand in groups on long, narrow, spike- like to racemose inflorescences . In the lower area of the inflorescences these groups are usually further apart, in the upper area they are more or less dense. The five bracts are densely dotted with glands. In contrast to other Fallopia species, the three outer bracts are only slightly winged or bluntly keeled. The fruits are 3.5 to 5 mm long, black, matt nuts that stand on a 1 to 3 mm long stem.

The number of chromosomes is 2n = 40.

Distribution and location

The homeland of the knotweed extends over large parts of Eurasia ; it is also native to North Africa . In North America , South America, Hawaii, Australia, New Zealand, the Azores and South Africa , it is now naturalized as a neophyte.

The knotweed has no special location requirements, but likes to grow on slightly acidic, sandy, loamy or humus soils. Since it is deep-rooted , it is insensitive to drought. It is a character species of the order Centauretalia cyani, but also occurs in societies of the class Secalietea, the order Polygono-Chenopodietalia or the Sisymbrion association. In the Allgäu Alps, it rises to an altitude of around 1000 meters.

meaning

Charred fruits have been observed since the early Neolithic . In the Neolithic village near Ehrenstein , they were found in such quantities that they give rise to the assumption that they were cultivated as a prehistoric "flour fruit".

In one study it was found that the leaves of the plant, which are part of traditional Mediterranean diets, have both potentially anti-diabetes and cell-protective properties.

Field weeds

The knotweed occurs mainly in spring crops , for example in summer cereals , winter cereals , root crops or orchards . The growth of the knotweed is windy and leafy, which can lead to harvest difficulties or a reduction in yield. For this reason, only a low density is tolerated in agriculture.

Web links

Commons : Knotweed - album with pictures, videos and audio files

Entry in GRIN Taxonomy for Plants
Knotweed. In: FloraWeb.de.
Distribution map for Germany. In: Floraweb .
Fallopia convolvulus (L.) Á. Löve In: Info Flora , the national data and information center for Swiss flora . Retrieved October 7, 2015.
Distribution in the northern hemisphere according to: Eric Hultén , Magnus Fries: Atlas of North European vascular plants 1986, ISBN 3-87429-263-0
Thomas Meyer: Data sheet with identification key and photos at Flora-de: Flora von Deutschland (old name of the website: Flowers in Swabia )

Individual evidence

↑ ^a ^b ^c ^d Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas . 8th edition. Verlag Eugen Ulmer, Stuttgart 2001, ISBN 3-8001-3131-5 . Page XXX.
^ Fallopia in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved August 11, 2017.
↑ Erhard Dörr, Wolfgang Lippert : Flora of the Allgäu and its surroundings. Volume 1, IHW, Eching 2001, ISBN 3-930167-50-6 , p. 454.
↑ Jens Lüning, Stone Age farmers in Germany , Bonn, Habelt 2000 p. 92.
↑ Pharmacological Research 52 (2005) Understanding local Mediterranean diets: A multidisciplinary pharmacological and ethnobotanical approach here online (PDF file; 944 kB) last viewed in August 2009

[Oberdorfer2001-1] Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas . 8th edition. Verlag Eugen Ulmer, Stuttgart 2001, ISBN 3-8001-3131-5 . Page XXX.

[GRIN-2] Fallopia in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved August 11, 2017.

[Dörr-Lippert-3] Erhard Dörr, Wolfgang Lippert : Flora of the Allgäu and its surroundings. Volume 1, IHW, Eching 2001, ISBN 3-930167-50-6 , p. 454.

[4] Jens Lüning, Stone Age farmers in Germany , Bonn, Habelt 2000 p. 92.

[5] Pharmacological Research 52 (2005) Understanding local Mediterranean diets: A multidisciplinary pharmacological and ethnobotanical approach here online (PDF file; 944 kB) last viewed in August 2009