![Aesculus carnea BotGartenMuenster PurpurKastanie 6685](https://upload.wikimedia.org/wikipedia/commons/4/48/Aesculus_carnea_BotGartenMuenster_PurpurKastanie_6685.jpg)
The
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
''Aesculus'' (
or ), with species called buckeye and horse chestnut, comprises 13–19 species of
flowering plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s in the family
Sapindaceae
The Sapindaceae are a family of flowering plants in the order Sapindales known as the soapberry family. It contains 138 genera and 1858 accepted species. Examples include horse chestnut, maples, ackee and lychee.
The Sapindaceae occur in tempera ...
. They are
tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
s and
shrub
A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...
s
native
Native may refer to:
People
* Jus soli, citizenship by right of birth
* Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory
** Native Americans (disambiguation)
In arts and entert ...
to the
temperate
In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...
Northern Hemisphere, with six species native to North America and seven to 13 species native to Eurasia. Several
hybrids occur. ''Aesculus'' exhibits a classical
Arcto-Tertiary distribution.
Mexican buckeye seedpods resemble the ''Aesculus'' seedpods, but belong to a different genus.
Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...
named the genus ''Aesculus'' after the Roman name for an edible acorn. Common names for these trees include "buckeye" and "horse chestnut", though they are not in the same order as the true chestnuts, ''
Castanea
The chestnuts are the deciduous trees and shrubs in the genus ''Castanea'', in the beech family Fagaceae. They are native to temperate regions of the Northern Hemisphere.
The name also refers to the edible nut (fruit), nuts they produce.
Th ...
'' in the
Fagales
The Fagales are an order of flowering plants, including some of the best-known trees. The order name is derived from genus ''Fagus'', beeches. They belong among the rosid group of dicotyledons. The families and genera currently included are a ...
. Some are also called white chestnut or red chestnut. In Britain, they are sometimes called conker trees because of their link with the game of
conkers
Conkers is a traditional children's game in Great Britain and Ireland played using the seeds of horse chestnut trees—the name 'conker' is also applied to the seed and to the tree itself. The game is played by two players, each with a conker ...
, played with the seeds, also called conkers.
Description
''Aesculus'' species have stout shoots with resinous, often sticky, buds, with opposite, palmately divided leaves, often very large—to across in the Japanese horse chestnut, ''A. turbinata''. Species are deciduous or evergreen. Flowers are showy, insect- or bird-pollinated, with four or five
petal
Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...
s fused into a lobed
corolla tube
Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually ...
, arranged in a panicle inflorescence. Flowering starts after 80–110
growing degree day
Growing degree days (GDD), also called growing degree units (GDUs), are a heuristic tool in phenology. GDD are a measure of heat accumulation used by horticulturists, gardeners, and farmers to predict plant and animal development rates such as the ...
s. The fruit matures to a
capsule diameter, usually globose, containing one to three seeds (often erroneously called a
nut
Nut often refers to:
* Nut (fruit), fruit composed of a hard shell and a seed, or a collective noun for dry and edible fruits or seeds
* Nut (hardware), fastener used with a bolt
Nut or Nuts may also refer to:
Arts, entertainment, and media Com ...
) per capsule. Capsules containing more than one seed result in flatness on one side of the seeds. The point of attachment of the seed in the capsule (hilum) shows as a large, circular, whitish scar. The capsule epidermis has "spines" (botanically: prickles) in some species, while other capsules are warty or smooth. At maturity, the capsule splits into three sections to release the seeds.
''Aesculus'' seeds were traditionally eaten, after
leaching
Leaching is the loss or extraction of certain materials from a carrier into a liquid (usually, but not always a solvent). and may refer to:
*Leaching (agriculture), the loss of water-soluble plant nutrients from the soil; or applying a small amoun ...
, by the
Jōmon people
is the generic name of several peoples who lived in the Japanese archipelago during the Jōmon period (). The Jōmon people may have consisted of multiple groups, which arrived and merged at different times in the Japanese archipelago, using multi ...
of Japan over about four millennia, until 300 AD.
All parts of the buckeye or horse chestnut tree are moderately toxic, including the nut-like seeds.
The toxin affects the gastrointestinal system, causing gastrointestinal disturbances. The USDA notes that the toxicity is due to
saponin
Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...
aescin
Aescin or escin is a mixture of saponins with anti-inflammatory, vasoconstrictor and vasoprotective effects found in ''Aesculus hippocastanum'' (the horse chestnut). Aescin is the main active component in horse chestnut, and is responsible for m ...
and
glucoside
A glucoside is a glycoside that is derived from glucose. Glucosides are common in plants, but rare in animals. Glucose is produced when a glucoside is hydrolysed by purely chemical means, or decomposed by fermentation or enzymes.
The name was o ...
aesculin
Aesculin, also called æsculin or esculin, is a coumarin glucoside that naturally occurs in the trees horse chestnut (''Aesculus hippocastanum''), California buckeye (''Aesculus californica''), prickly box (''Bursaria spinosa''), and daphnin (the ...
, with
alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...
s possibly contributing.
Native Americans used to crush the seeds and the resulting mash was thrown into still or sluggish waterbodies to stun or kill fish.
They then boiled and drained (leached) the fish at least three times to dilute the toxin's effects.
New shoots from the seeds also have been known to kill grazing cattle.
The genus was considered to be in the ditypic family
Hippocastanaceae
Hippocastanoideae is a subfamily of flowering plants in the soapberry family Sapindaceae. The group was formerly treated as the separate families Aceraceae and Hippocastanaceae. Molecular phylogenetic research by Harrington et al. (2005) has s ...
along with ''
Billia
''Billia'' is a genus of trees in the family Sapindaceae and native to the Americas, from central Mexico to Ecuador. The wood is used in carpentry.
Species
The following species are recognized:
* ''Billia hippocastanum''
* ''Billia rosea
...
'',
but phylogenetic analyses of morphological
and molecular data
have more recently caused this family, along with the
Aceraceae
Aceraceae were recognized as a family of flowering plants also called the maple family. They contain two to four genera, depending upon the circumscription, of some 120 species of trees and shrubs. A common characteristic is that the leaves are ...
(
maple
''Acer'' () is a genus of trees and shrubs commonly known as maples. The genus is placed in the family Sapindaceae.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 nd more or less continuously updated since http ...
s and ''
Dipteronia
''Dipteronia'' is a genus with two living and one extinct species in the soapberry family Sapindaceae. The living species are native to central and southern China, The fossil species has been found in Middle Paleocene to Early Oligocene sediments ...
''), to be included in the soapberry family (Sapindaceae).
Selected species
The species of ''Aesculus'' include:
Cultivation
The most familiar member of the genus worldwide is the common horse chestnut, ''
Aesculus hippocastanum
''Aesculus hippocastanum'', the horse chestnut, is a species of flowering plant in the maple, soapberry and lychee family Sapindaceae. It is a large, deciduous, synoecious (hermaphroditic-flowered) tree. It is also called horse-chestnut, Europ ...
''. The yellow buckeye, ''
Aesculus flava
''Aesculus flava'', the yellow buckeye, common buckeye, or sweet buckeye, is a species of deciduous tree. It is native to the Ohio Valley and Appalachian Mountains of the Eastern United States. It grows in mesophytic forest or floodplains, genera ...
'' (syn. ''A. octandra''), is also a valuable ornamental tree with yellow flowers, but is less widely planted. Among the smaller species is the bottlebrush buckeye, ''
Aesculus parviflora
''Aesculus parviflora'', the bottlebrush buckeye, is a species of suckering deciduous shrub in the family Sapindaceae. The species is native to the southeastern United States, where it is found primarily in Alabama and Georgia, with a disjunct p ...
'', a flowering shrub. Several other members of the genus are used as ornamentals, and several horticultural hybrids have also been developed, most notably the red horse chestnut
''Aesculus'' × ''carnea'', a hybrid between ''A. hippocastanum'' and ''A. pavia''.
In art
![Reims Notre Dame column detail - horse chestnut](https://upload.wikimedia.org/wikipedia/commons/e/e7/Reims_Notre_Dame_column_detail_-_horse_chestnut.jpg)
Interpretations of the tree leaves can be seen in architectural details in the
Reims Cathedral
, image = Reims Kathedrale.jpg
, imagealt = Facade, looking northeast
, caption = Façade of the cathedral, looking northeast
, pushpin map = France
, pushpin map alt = Location within France
, ...
.
In history
The horse chestnut was not native to Britain and was only introduced from Europe in 1650 (on the eastates of both
Dawyck House
Dawyck House is a historic house at Dawyck, in the parish of Drumelzier in the former Peeblesshire, in the Scottish Borders area of Scotland. The alternative name is 'Dalwick House'. Canmore ID 49816.
Dawyck Castle was built about the Thirteenth ...
and
Stobo Castle
Stobo Castle is located at Stobo in the Scottish Borders, in the former county of Peeblesshire. The Manor of Stobo was originally owned by the Balfour family. It became the family seat of the Graham-Montgomery Baronets from 1767. The buildin ...
).
[Scottish Garden Buildings by Tim Buxbaum p.11]
The leaf of Aesculus was the official symbol of
Kyiv
Kyiv, also spelled Kiev, is the capital and most populous city of Ukraine. It is in north-central Ukraine along the Dnieper, Dnieper River. As of 1 January 2021, its population was 2,962,180, making Kyiv the List of European cities by populat ...
on its
coat of arms
A coat of arms is a heraldry, heraldic communication design, visual design on an escutcheon (heraldry), escutcheon (i.e., shield), surcoat, or tabard (the latter two being outer garments). The coat of arms on an escutcheon forms the central ele ...
used from 1969 to 1995.
It remains an official symbol of Kyiv to this day.
In the
1840 U.S. presidential campaign, candidate
William Henry Harrison
William Henry Harrison (February 9, 1773April 4, 1841) was an American military officer and politician who served as the ninth president of the United States. Harrison died just 31 days after his inauguration in 1841, and had the shortest pres ...
called himself the "log cabin and hard cider candidate", portraying himself sitting in a log cabin made of buckeye logs and drinking hard cider, causing Ohio to become known as "the Buckeye State".
In
Geneva
Geneva ( ; french: Genève ) frp, Genèva ; german: link=no, Genf ; it, Ginevra ; rm, Genevra is the List of cities in Switzerland, second-most populous city in Switzerland (after Zürich) and the most populous city of Romandy, the French-speaki ...
,
Switzerland
). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...
, an
official chestnut tree is used to indicate the beginning of the
Spring
Spring(s) may refer to:
Common uses
* Spring (season), a season of the year
* Spring (device), a mechanical device that stores energy
* Spring (hydrology), a natural source of water
* Spring (mathematics), a geometric surface in the shape of a ...
; every year since 1818, the tree is observed by the secretary of the
Grand Council of Geneva
The Grand Council of Geneva (french: Grand Conseil de Genève) is the legislature of the canton of Geneva, in Switzerland. Geneva, styled as a 'Republic and Canton', has a unicameral legislature. The Grand Council was established in its prese ...
(the local parliament), and the opening of the first leaf is recorded and announced publicly. Over the years, four different horse chestnut trees have been used for these recordings.
See also
*
Anne Frank tree
The Anne Frank tree ( nl, Anne Frankboom or, incorrectly, ''Anne Frank boom'') was a horse-chestnut tree (''Aesculus hippocastanum'') in the city center of Amsterdam that was featured in Anne Frank's ''The Diary of a Young Girl''. Anne Frank de ...
References
Explanatory notes
Citations
External links
Germplasm Resources Information Network: ''Aesculus''* Forest, F., Drouin, J. N., Charest, R., Brouillet, L., & Bruneau A. (2001)
"A morphological phylogenetic analysis of Aesculus L. and Billia Peyr. (Sapindaceae)" ''Can. J. Bot.'' 79 (2): 154–169. .
King's American Dispensatory
{{Authority control
Sapindaceae genera
Taxa named by Carl Linnaeus