Hornbeam

Hornbeam — Plants in the genus Carpinus (Cár-pi-nus) are commonly called Hornbeams. They are relatively small hardwood trees. Many botanists place the hornbeams in the birch family Betulaceae, though some group them with the hazels (Corylus) and hop-hornbeams (Ostrya) in a segregate family, Corylaceae. The 30-40 species occur across much of the north temperate regions, with the greatest number of species in east Asia, particularly China. Only two species occur in Europe, and only one in eastern North America.

The leaves are deciduous, alternate, and simple with a serrated margin, and typically vary from 3-10 cm in length. The flowers are wind-pollinated pendulous catkins, produced in spring. The male and female flowers are on separate catkins, but on the same tree (monoecious). The fruit is a small nut about 3-6 mm 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. There are typically 10-30 seeds on each seed catkin.

Hornbeams are used as food plants by the larvae of some Lepidoptera species including Autumnal Moth, Common Emerald, Feathered Thorn, Svensson’s Copper Underwing and Winter Moth (recorded on European Hornbeam) as well as the Coleophora case-bearers C. currucipennella and C. ostryae.