Hornbeam

Hornbeams are hardwood trees in the plant genus Carpinus in the family Betulaceae. Its species occur across much of the temperate regions of the Northern Hemisphere.

Common names

The common English name hornbeam derives from the hardness of the woods (likened to horn) and the Old English beam, "tree" (cognate with Dutch Boom and German Baum).

The American hornbeam is also occasionally known as blue-beech, ironwood, or musclewood, the first from the resemblance of the bark to that of the American beech Fagus grandifolia, the other two from the hardness of the wood and the muscled appearance of the trunk and limbs.

The botanical name for the genus, Carpinus, is the original Latin name for the European species, although some etymologists derive it from the Celtic for a yoke.<ref>Gledhill D. 1985. The Names of Plants. Cambridge University Press Template:ISBN</ref>

Description

File:Carpinus betulus 001.JPG

European hornbeam in Germany, during May

Hornbeams are small, slow-growing, understory trees with a natural, rounded form growing Template:Convert tall and wide; the exemplar species—the European hornbeam—reaches a maximum height of Template:Convert.<ref name="Stace-2010">Template:Cite book</ref>Template:Rp

Leaves are deciduous, dark-green, alternate and simple with a coarsely-serrated margin, varying from Template:Convert in length. In autumn, leaves turn various shades of yellow, orange and red. Hornbeam saplings, stressed trees, and the lower branches of mature trees may exhibit marcescence—where leaves wither with autumn but abscission (leafdrop) is delayed until spring.<ref>Template:Cite book</ref>

The smooth, gray trunk and larger branches of a mature tree exhibit a distinctive muscle-like fluting.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

As with other members of the birch family, hornbeam flowers are wind-pollinated pendulous catkins, produced in spring. Male and female flowers are on separate catkins, but on the same tree (monoecious). Female flowers give way to distinctive clusters of winged seeds that somewhat resemble the hops-like seeds of ironwood.<ref>Template:Cite journal</ref>

The fruit is a small nut about Template:Convert long, held in a leafy bract; the bract may be either trilobed or simple oval, and is slightly asymmetrical. The asymmetry of the seedwing makes it spin as it falls, improving wind dispersal. The shape of the wing is important in the identification of different hornbeam species. Typically, 10–30 seeds are on each seed catkin.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>Template:Cite book</ref>

Taxonomy

Formerly some taxonomists segregated them with the genera Corylus (hazels) and Ostrya (hop-hornbeams) in a separate family, Corylaceae. Modern botanists place Carpinus in the subfamily Coryloideae of the family Betulaceae.<ref name="Pigg-2003">Template:Cite journal</ref><ref name="Forest-2005">Template:Cite journal</ref> Species of Carpinus are often grouped into two subgenera Carpinus subgenus Carpinus and Carpinus subgenus Distegicarpus.

Phylogentic analyses have shown that Ostrya likely evolved from a Carpinus ancestor somewhere in C. subg. Distegicarpus making Carpinus paraphyletic. The fossil record of the genus extends back to the Early Eocene, Ypresian of northwestern North America, with the species Carpinus perryae described from fossil fruits found in the Klondike Mountain Formation of Republic, Washington.<ref name="Pigg-2003" />

File:Carpinus austrobalcanica (2) Photo University of Belgrade Nevena Kuzmanović.jpg

Carpinus austrobalcanica, southern Balkan hornbeam, first described 2024

Species

43 species are currently accepted.<ref name="POWO">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

• Carpinus austrobalcanica N.Kuzmanović, D.Lakušić, I.Stevanoski, P.Schönswetter, B.Frajman – Southern Albania, Northwestern Greece
• Carpinus betulus Template:Small – European hornbeam - Europe to Western Asia; naturalized in North America.<ref name="RHS-2003"/>
• Carpinus caroliniana Template:Small – American hornbeam - Eastern North America
• Carpinus chuniana Template:Small – Guangdong, Guizhou, Hubei
• Carpinus cordata Template:Small – Sawa hornbeam - Primorye, China, Korea, Japan
• Carpinus dayongiana Template:Small – Hunan
• Carpinus faginea Template:Small – Nepal, Himalayas of northern India
• Carpinus fangiana Template:Small<ref name="RogersTrees&Shrubs">{{#invoke:citation/CS1|citation

|CitationClass=web }}</ref> – Sichuan, Guangxi

• Carpinus fargesiana Template:Small – central and east-central China
• Carpinus firmifolia Template:Small – Guizhou: Guiyang Shi
• Carpinus gigabracteatus Template:Small – Yunnan
• Carpinus hebestroma Template:Small – Taiwan
• Carpinus henryana Template:Small – southern China
• Carpinus insularis Template:Small – Hong Kong
• Carpinus japonica Template:Small – Japanese hornbeam - Japan
• Carpinus kawakamii Template:Small – Taiwan, southeastern China
• Carpinus kweichowensis Template:Small – Guizhou, Yunnan
• Carpinus langaoensis Template:Small – Shaanxi, China
• Carpinus laxiflora Template:Small – Aka-shide hornbeam - Japan, Korea
• Carpinus lipoensis Template:Small – Guizhou
• Carpinus londoniana Template:Small – southern China, northern Indochina
• Carpinus luochengensis Template:Small – Guangxi
• Carpinus mengshanensis Template:Small – Shandong
• Carpinus microphylla Template:Small – Guangxi
• Carpinus mollicoma Template:Small – Tibet, Sichuan, Yunnan
• Carpinus monbeigiana Template:Small – Tibet, Yunnan
• Carpinus omeiensis Template:Small – Sichuan, Guizhou
• Carpinus orientalis Template:Small – Oriental hornbeam - Hungary, Balkans, Italy, Crimea, Turkey, Iran, Caucasus
• Carpinus paohsingensis Template:Small – China
• †Carpinus perryae Template:Small - Ypresian, Klondike Mountain Formation
• Carpinus polyneura Template:Small – southern China
• Carpinus pubescens Template:Small – China, Vietnam
• Carpinus purpurinervis Template:Small – Guizhou, Guangxi
• Carpinus putoensis Template:Small – Putuo hornbeam - Zhejiang
• Carpinus rankanensis Template:Small – Taiwan
• Carpinus rupestris Template:Small – Yunnan, Guangxi, Guizhou
• Carpinus × schuschaensis Template:Small (C. betulus × C. orientalis) – Caucasus and northern Iran
• Carpinus shensiensis Template:Small – Gansu, Shaanxi
• Carpinus shimenensis Template:Small – Hunan
• †Carpinus tengshongensis Template:Small<ref>Template:Cite journal</ref> – Pliocene Yunnan
• Carpinus tibetana Template:Small – Tibet
• Carpinus tientaiensis Template:Small – Zhejiang: Tianmu Shan
• Carpinus tropicalis Template:Small – Mexico, Central America
• Carpinus tsaiana Template:Small – Yunnan, Guizhou
• Carpinus tschonoskii Template:Small – Asian Hornbeam, Chonosuki's Hornbeam - southern China, Korea, Japan
• Carpinus turczaninovii Template:Small – Korean hornbeam<ref>Template:Cite book</ref> - China, Korea, Japan
• Carpinus viminea Template:Small – China, Korea, Himalayas, northern Indochina

Distribution and habitat

The 43 species occur across much of the temperate regions of the northern hemisphere, with the greatest number of species in east Asia, particularly China. Only three species occur in Europe, only one in eastern North America, and one in Mesoamerica.<ref name="KewChecklist">{{#invoke:citation/CS1|citation |CitationClass=web }}Template:Dead link</ref><ref>Flora of China, Vol. 4 Page 289, 鹅耳枥属 e er li shu, Carpinus Linnaeus, Sp. Pl. 2: 998. 1753. </ref><ref>Flora of North America, Vol. 3, Hornbeam, Carpinus Linnaeus, Sp. Pl. 2: 998. 1753; Gen. Pl. ed. 5, 432, 1754. </ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Carpinus betulus can be found in Europe, Turkey and Ukraine.<ref name="RHS-2003">Template:Cite book</ref>

Ecology

File:20140204Hainbuche Neulussheim3.jpg

Hornbeam trunk

Hornbeams are used as food plants by the larvae of some Lepidoptera species, including autumnal moth, common emerald, feathered thorn, walnut sphinx, Svensson's copper underwing, and winter moth (recorded on European hornbeam) as well as the Coleophora case-bearers C. currucipennella and C. ostryae.<ref name="USDA-1972">Template:Cite book</ref>

Uses

Hornbeams yield a very hard timber, giving rise to the name "ironwood".<ref name="Eichhorn-2011">Archived at GhostarchiveTemplate:Cbignore and the Wayback MachineTemplate:Cbignore: {{#invoke:citation/CS1|citation |CitationClass=web }}Template:Cbignore</ref> Dried heartwood billets are nearly white and are suitable for decorative use. For general carpentry, hornbeam is rarely used, partly due to the difficulty of working it.

The wood is used to construct carving boards, tool handles, handplane soles, coach wheels, piano actions, shoe lasts, and other products where a very tough, hard wood is required.

The wood can also be used as gear pegs in simple machines, including traditional windmills.<ref name="Eichhorn-2011"/> It is sometimes coppiced to provide hardwood poles. It is also used in parquet flooring and for making chess pieces.

External links

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|CitationClass=web }}