Horse chestnuts
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Common horse chestnut ( Aesculus hippocastanum ) |
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The horse chestnut ( Aesculus ) are a genus of flowering plants in the family of the soap tree plants (Sapindaceae). The twelve or so species are native to the northern hemisphere in North America and Eurasia . In Europe the common horse chestnut is widely planted as a park and avenue tree. A partial name correspondence with the sweet chestnut ( Castanea sativa ) is based on a superficial similarity of the fruits, not on relationship; both belong to different families.
description
Appearance and leaves
The horse chestnut species are deciduous trees or shrubs . They are among the shallow roots . The winter buds are large, often resinous, and consist of several pairs of imbricate scales. The outside of the scales is bald or slightly hairy.
The constantly against arranged on the branches leaves are divided into petiole and leaf blade. The leaf blades are finger-shaped and consist of five to eleven pinnate leaves . The leaflets have a serrated to serrated edge .
Inflorescences and flowers
The inflorescences are cylindrical to conical thyrses with simple side branches. Bracts are missing.
The mostly large and showy flowers are four or five-fold with a double flower envelope . The sepals are fused and form a tubular to bell-shaped calyx tube. The petals are often unequal. They are nailed, the plate is obovate, lanceolate or spatulate. The ovary does not stand on a gynophore , the stylus is long and slender, the scar , when compressed, is spherical, sometimes slightly lobed.
Fruits and seeds
The spherical to pear-shaped capsule fruits often contain only one seed . The pericarp is usually smooth, less often wrinkled or prickly, the latter in the common horse chestnut . Like the capsule fruit, the seeds are spherical to pear-shaped and 2 to 7 cm in size. The seed coat is brown, the umbilicus ( hilum ) is large, pale and takes up a third to half of the seed.
Chromosome set
The basic chromosome number is x = 20.
Distribution and location requirements
The oldest found fossils of the genus date from the Paleocene ; in Europe the oldest finds come from the Oligocene .
The genus Aesculus is widespread in the northern hemisphere and occurs here mainly in the temperate climatic zone. The distribution area of the genus is fragmented ( disjoint ) and is divided into three sub-areas: In North America there are seven species from the west to the east coast, in Asia five or six species from the Himalayan area through Southeast Asia and China to Japan. One species, the common horse chestnut, is native to south-eastern Europe, but is widely planted in Europe. The horse chestnut genus ( Aesculus ) is the only one of the three genera of the subfamily of the horse chestnut family (Hippocastanoideae) that was cultivated by humans.
Systematics
The genus Aesculus was established by Carl von Linné .
From their natural habitat in Europe, horse chestnuts are only represented by one species; numerous species can be found in Asia and North America.
The genus Aesculus is divided into several sections:
- Parryanae Wiggins Section
- Aesculus parryi A.Gray : This endemic occurs only in northwest Baja California .
- Section Aesculus (Syn .: Hippocastanum (Mill.) K. Koch )
- Japanese horse chestnut ( Aesculus turbinata flower ): It is only found in Japan.
- Common horse chestnut ( Aesculus hippocastanum L. ): It is endemic to the Balkans and is widely planted in the temperate regions.
- Section Calothyrsus (Spach) Pax
- California horse chestnut ( Aesculus californica (Spach) Nutt. ): It is endemic to California .
- Aesculus assamica handle. : It is common in Southeast Asia.
- Chinese horse chestnut ( Aesculus chinensis Bunge ): It occurs in China.
- Indian horse chestnut ( Aesculus indica (Wall. Ex Camb.) Hook. )
- Aesculus wilsonii Rehder , was added to Aesculus chinensis in 2005 and is no longer listed as a separate species.
- Section Macrothyrsus (Spach) K. Koch
- Bush horse chestnut ( Aesculus parviflora Walter ): It occurs in Georgia and Alabama.
- Section Pavia (Mill.) Pers.
- Ohio horse chestnut ( Aesculus glabra Willd. ): It occurs in the southeastern United States.
- Yellow horse chestnut ( Aesculus flava Sol. , Formerly Aesculus octandra Marshall ): It occurs in the southeastern United States.
- Aesculus sylvatica W.Bartram : It occurs in the southeastern USA.
- Red horse chestnut ( Aesculus pavia L. ): It occurs in the USA.
Among the horse chestnuts there are numerous inter-species hybrids, some of which are also important as ornamental trees , such as the red horse chestnut ( Aesculus × carnea Hayne , Aesculus hippocastanum × Aesculus pavia ).
Naming
The genus name Aesculus was first transferred to the horse chestnut by Carl von Linné . In ancient times, the Latin word aesculus was used to denote a species of oak that was sacred to Jupiter , grew on mountains, was tall and made of solid wood. The word possibly referred to the grape oak ( Quercus petraea ).
The common German name horse chestnut actually refers to the common horse chestnut . It is based on the seeds that are visually similar to the sweet chestnut , which the Ottomans brought with them as horse fodder and as a remedy for horse coughing, and thus reached Central Europe. The addition "Ross" was used to distinguish these inedible seeds from the edible chestnuts that have been known for a long time.
use
Most Aesculus species are fast-growing, decorative leafy, medium-sized to large trees (only a few species are shrub-like) with striking inflorescences with numerous often colored flowers. Different species and their varieties are therefore often planted as park, avenue and street trees almost all over the world .
All parts of the horse chestnut are slightly poisonous. The digestive disorders that occur when taking parts of plants are probably caused by the saponins and the glucoside esculin . You may also carry alkaloids help. Horses can suffer coordination disorders after consuming chestnuts, while deer and other mammals can neutralize the substances contained in the digestive tract.
The chestnuts were eaten by the people on the Japanese islands during the Jōmon period , after the incompatible substances had been leached out by boiling and watering.
American Indians crushed chestnuts and poured the pulp into calm waters to stun or kill fish living there.
For the use of the species widespread in Europe see common horse chestnut #use .
Pests
Since the 1980s the horse chestnut leaf miner has spread from the Balkans throughout Europe and increasingly also in the neighboring Asian countries , which almost exclusively infects the common horse chestnut, but to a lesser extent the Japanese horse chestnut .
supporting documents
- Nianhe Xia, Nicholas J. Turland: Aesculus. , Pp. 2–4 - same text online and printed work (pdf; 197 kB) In: Wu Zheng-yi, Peter H. Raven, Deyuan Hong (ed.): Flora of China . Volume 12: Hippocastanaceae through Theaceae . Science Press / Missouri Botanical Garden Press, Beijing / St. Louis 2007, ISBN 978-1-930723-64-1 (English). (Sections Description and Distribution)
Individual evidence
- ↑ Contributions to the horse chestnut appendix: Overview of the types and varieties of the chestnut. (Page 80) www.lwf.bayern.de (pdf; 10.8 MB)
- ↑ James W. Hardin: A Revision of the American Hippocastanaceae-II. In: Brittonia , Volume 9, 1957, pp. 173-195.
- ↑ Nicholas J. Turland, Nianhe Xia: A New Combination in Chinese Aesculus (Hippocastanaceae). In: Novon 15, September 21, 2005, pp. 488–489 ( web document , pdf)
- ↑ a b Siegmund Seybold (Ed.): Schmeil-Fitschen interactive (CD-Rom), Quelle & Meyer, Wiebelsheim 2001/2002, ISBN 3-494-01327-6 .
- ↑ a b Helmut Genaust: Etymological dictionary of botanical plant names. 3rd, completely revised and expanded edition. Birkhäuser, Basel / Boston / Berlin 1996, ISBN 3-7643-2390-6 , p. 42 (reprint ISBN 3-937872-16-7 ).
- ^ Alan Hall: The Wild Food Trail Guide , second. Edition, Holt, Rhinehart and Winston, New York 1976, p. 214.
- ^ Lee Peterson: A field guide to edible wild plants of eastern and central North America . Houghton Mifflin Co., Boston 1977, p. 172.
- ↑ a b Guy Nelson: Ohio Buckeye ( Aesculus glabra Willd.), Plant Guide . US Department of Agriculture, Natural Resources Conservation Service, Washington, DC 2006.
- ↑ Lon D. Lewis: Feeding and care of the horse . Wiley-Blackwell, 1995, ISBN 9780683049671 (Retrieved October 21, 2011).
- ^ Jack R. Harlan: The Living Fields: Our Agricultural Heritage , 1st publ. Edition, Cambridge Univ. Press, Cambridge [and a.] 1995, ISBN 0-521-40112-7 , p. 15.
- ↑ T. Akazawa, CM Aikens: Prehistoric Hunter-Gathers in Japan . University of Tokyo Press, 1986.
- ↑ CM Aikens, T. Higachi: Prehistory of Japan . New York Academic Press, 1982.
- ↑ Thomas R. Dale, Dixie B. Scogin: 100 woody plants of Louisiana . The Herbarium of Northeast Louisiana University, Monroe, Louisiana 1988, p. 118.
Web links
- Laurence C. Hatch: Nos Aesculus Page , plantnames.org 1998–2005 (Eng.)
- 2012: The bacterium Pseudomonas syringae pv.aesculi is spreading in North Rhine-Westphalia and elsewhere