Hornbeam wood is so hard it earned the nickname ironwood
Run a hand over a mature hornbeam and the smooth grey trunk ripples like flexed muscle. The wood beneath is so tough that carpenters rarely bother with it for everyday work. Instead it went into the parts that take a beating: windmill gear pegs, coach wheels, tool handles, piano actions and chess pieces.
The name says it all. Horn refers to the hardness of the wood, and beam is Old English for tree, related to the Dutch boom and German Baum. In North America the local species is also called blue-beech, for bark that resembles the American beech, and ironwood or musclewood for its toughness and its sinewy, fluted trunk. The genus name Carpinus was the Latin word for the European species, though some etymologists link it to a Celtic word for yoke.
Most hornbeams are small, slow-growing trees of the forest understorey, reaching 4.5 to 9 metres with a rounded crown, though the European hornbeam can top 32 metres. Their toothed leaves turn yellow, orange and red in autumn, and young or stressed trees often cling to their dead leaves until spring. In spring they hang out wind-pollinated catkins, male and female on the same tree. Each small nut rides on a lopsided leafy wing that makes it spin as it drops, carrying it further on the breeze, and the wing's shape helps botanists tell species apart.
There are 45 species across the temperate Northern Hemisphere, most of them in East Asia, particularly China; Europe has just three and eastern North America only one. Genetic studies suggest the hop-hornbeams evolved from within the group. Fossil fruits from the Klondike Mountain Formation in Washington state show the genus already existed in the Early Eocene. The leaves feed the caterpillars of several moths, including the winter moth.
Dried heartwood is nearly white and handsome enough for decorative work, but the difficulty of cutting it keeps it out of general carpentry. It finds its place where toughness matters: carving boards, plane soles, shoe lasts and parquet floors. Trees are sometimes coppiced to produce straight hardwood poles.
Source: Hornbeam
