Square willowherb
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Square willowherb ( Epilobium tetragonum ) |
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The square willowherb ( Epilobium tetragonum ) in the broader sense (see left) is an herbaceous plant from the evening primrose family (Onagraceae).
description
The square willowherb reaches heights of between 30 and 100 centimeters. It is a rosette plant with perennial buds ( hemicryptophyte , herbaceous chamaephyte ) lying close to the surface . The stems are rounded below. At the top they have two to four raised ridges that are often reddish. While the stems of the common square willowherb are bare, the gray-green willowherb has a pressed gray hair. The leaves of the first-mentioned subspecies are lanceolate to ovate and have sharp cartilaginous serrations forward, fresh green, shiny and almost bare. The leaves of the gray-green willowherb, on the other hand, are dull with scattered teeth, slightly bluish green and often reddish tinged.
The flowers are 4 to 6 millimeters ( Epilobium tetragonum subsp. Tetragonum ) or 8.5 millimeters ( Epilobium tetragonum subsp. Lamyi ) long, in Epilobium tetragonum subsp. tournefortii even 7 to 11.5 mm long. The petals are pale pink. The scar is clubbed. The capsules are hairy when pressed, gray-green and glandless. The seeds are evenly finely warty.
The two subspecies occurring in Central Europe have the chromosome number 2n = 36.
Occurrence
distribution
The square willowherb is common throughout Europe with the exception of Scandinavia to Central Asia. There are also populations in Africa. The common square willowherb is the most widespread. The gray-green willowherb is not found in Asia.
Locations
The square willowherb often grows on fresh to moderately dry, nutrient-rich clay soils. It is a light to partial shade plant. The subspecies In Central Europe, tetragonum grows primarily in Galio-Urticenea and Sisymbrion societies, but also in Filipendulion or Agrostietalia societies. The subspecies lamyi, on the other hand, prefers Alliarion and Polygono-Chenopodietalia societies.
Systematics
Two subspecies are known in Central Europe:
- The Ordinary four-edged fireweed ( Epilobium tetragonum subsp. Tetragonum )
- The gray-green willowherb ( Epilobium tetragonum subsp. Lamyi (FWSchultz) Nyman ).
In the Mediterranean there is a third subspecies:
- Epilobium tetragonum subsp. tournefortii (Michalet) Léveillé . Their petals are 7 to 11.5 mm long and, in contrast to the other two subspecies, the stigma rises above the stamens at full bloom.
photos
blossom
fruit
inflorescence
literature
- Henning Haeupler, Thomas Muer: picture atlas of the fern and flowering plants of Germany . Ed .: Federal Agency for Nature Conservation (= The fern and flowering plants of Germany . Volume 2 ). Eugen Ulmer, Stuttgart (Hohenheim) 2000, ISBN 3-8001-3364-4 .
Individual evidence
- ↑ a b 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. 686 .
- ^ A b Peter Hamilton Raven: Epilobium L. In: TG Tutin, VH Heywood, NA Burges, DM Moore, DH Valentine, SM Walters, DA Webb (eds.): Flora Europaea . Volume 2: Rosaceae to Umbelliferae . Cambridge University Press, Cambridge 1968, ISBN 0-521-06662-X , pp. 310 (English, limited preview in Google Book Search).
Web links
- Epilobium tetragonum s. l.
- Square willowherb. In: FloraWeb.de.
- Profile and distribution map for Bavaria . In: Botanical Information Hub of Bavaria .
- Epilobium tetragonum L. s. l. In: Info Flora , the national data and information center for Swiss flora . Retrieved December 29, 2015.
- Thomas Meyer: Data sheet with identification key and photos at Flora-de: Flora von Deutschland (old name of the website: Flowers in Swabia )
- Epilobium tetragonum subsp. tetragonum
- Square willowherb . In: BiolFlor, the database of biological-ecological characteristics of the flora of Germany.
- Epilobium tetragonum L. s. st. In: Info Flora , the national data and information center for Swiss flora . Retrieved December 29, 2015.
- Distribution in the northern hemisphere from: Eric Hultén, Magnus Fries: Atlas of North European vascular plants. 1986, ISBN 3-87429-263-0 at Den virtuella floran. (swedish).
- Epilobium tetragonum subsp. lamyi
- Square willowherb . In: BiolFlor, the database of biological-ecological characteristics of the flora of Germany.
- Epilobium tetragonum subsp. lamyi (FW Schultz) Nyman In: Info Flora , the national data and information center for Swiss flora . Retrieved December 29, 2015.
- Distribution in the northern hemisphere from: Eric Hultén, Magnus Fries: Atlas of North European vascular plants. 1986, ISBN 3-87429-263-0 at Den virtuella floran. (swed.)
