Mexican fleabane

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Mexican fleabane
Mexican fleabane (Erigeron karvinskianus)

Mexican fleabane ( Erigeron karvinskianus )

Systematics
Order : Astern-like (Asterales)
Family : Daisy family (Asteraceae)
Subfamily : Asteroideae
Tribe : Astereae
Genre : Fleabane Herbs ( Erigeron )
Type : Mexican fleabane
Scientific name
Erigeron karvinskianus
DC.

The Mexican fleabane ( Erigeron karvinskianus ), also Spanish daisies , Karwinsky fleabane or wall Daisy called, is a species of the genus erigeron ( Erigeron ) within the family of the daisy family (Asteraceae). It is common in Central and South America and is used as an ornamental plant.

description

Habit, leaves and flower heads
Habit, leaves and flower heads
Macro shot of an inflorescence

Vegetative characteristics

The Mexican fleabane is a basal woody, perennial , herbaceous plant with loosely branched stems . The carpet-forming plant can reach heights of 10 to 100 centimeters, the carpet up to 1 meter.

The gray-green, hairy leaves are elliptical-lanceolate with a length of up to 4 centimeters. The lower stem leaves are more or less three-lobed, the upper ones are lanceolate and smaller.

Inflorescence and flower

The flowering period extends mainly in summer from March to November. The cup-shaped inflorescences stand together individually or in loose umbrella-like overall inflorescences in pairs to five. The flower heads have a diameter of about 2 centimeters. The flower head contains tubular and 45 to 80 ray florets. The zygomorphic ray- flowers (= ray-flowers), which open up to white and later turn pink to purple in color, are 5 to 6 millimeters long. The yellow tubular flowers (= disc flowers) are 2 to 3.1 millimeters long.

fruit

1 to 1.4 mm long, two-ribbed achenes are formed. The pappus on the achenes consists of 15 to 27 bristles.

Chromosome number

The number of chromosomes is 2n = 36.

Persisted as an invasive plant

distribution

The original distribution area of Erigeron karvinskianus extends from Mexico via Central ( Guatemala to Panama ) to South America .

Erigeron karvinskianus was introduced to Europe as an ornamental plant in the 18th century . Today the species is established as a neophyte on all the Azores islands , Madeira , the Canaries and in southern Europe as far as Switzerland (for example in the canton of Ticino ) and in southern Germany .

It often grows there on damp walls, especially bank walls, in ravines and on rocks up to an altitude of 800 meters. The Mexican fleabane can form thick carpets that can suppress natural vegetation.

There is its own plant society Erigeronetum karvinskiani Oberd. 1969 from the association Centrantho-Parietarion at wall locations, where the fleabane can be found in the company of plants such as snapdragon ( Antirrhinum majus ), Asarina procumbens , caper ( Capparis spinosa ), gold lacquer ( Erysimum cheiri ) as well as red spur flower ( Centranthus ruber ), yellow lark spur ( Corydalis lutea ) and cymbal herb ( Cymbalaria muralis ).

Taxonomy

The first description of Erigeron karvinskianus was in 1836 by Augustin-Pyrame de Candolle . The specific epithet Erigeron karvinskianus honors Wilhelm Friedrich von Karwinsky von Karwin (1780–1855). A synonym of Erigeron karvinskianus DC. is Erigeron mucronatus DC.

use

Some varieties are used as an ornamental plant. It is cultivated as an annual plant , but can also survive the winter in Central Europe with some protection.

literature

  • Eckehart J. Jäger, Friedrich Ebel, Peter Hanelt, Gerd K. Müller (eds.): Excursion flora from Germany . Founded by Werner Rothmaler. tape 5 : Herbaceous ornamental and useful plants . Springer, Spektrum Akademischer Verlag, Berlin / Heidelberg 2008, ISBN 978-3-8274-0918-8 .
  • DuMont's large plant encyclopedia , Volume 1, A – J: DuMont Buchverlag, Cologne. 3rd edition, 2000, ISBN 3-7701-4350-7 .
  • Guy L. Nesom: Erigeron. Erigeron karvinskianus , p. 337 - the same text online as the printed work , In: Flora of North America Editorial Committee (Hrsg.): Flora of North America North of Mexico. Volume 20: Magnoliophyta: Asteridae, part 7: Asteraceae, part 2 (Astereae, Senecioneae) , Oxford University Press, New York and Oxford. 2006, ISBN 0-19-530564-7 . (Sections Description and Taxonomy)

Individual evidence

  1. ^ Erich Oberdorfer : Plant-sociological excursion flora for Germany and neighboring areas . With the collaboration of Angelika Schwabe and Theo Müller. 8th, heavily revised and expanded edition. Eugen Ulmer, Stuttgart (Hohenheim) 2001, ISBN 3-8001-3131-5 , pp.  914 .
  2. ↑ Dietmar Brandes: Asplenietea companies at secondary locations in Central Europe .

Web links

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