This section is from the book "Wayside And Woodland Blossoms", by Edward Step. Also available from Amazon: Wayside And Woodland Blossoms: A Guide To British Wild-Flowers.
It is in our experience that though many townsmen think they know the Beech there are comparatively few of them that cannot be deceived into accepting the Hornbeam as Fagns sylvatica. It must be admitted that there is a strong superficial resemblance to a small Beech; but on closer examination it will be found that the differences are greater than the likeness. The Hornbeam has a light-grey smooth bark, but instead of the very round trunk of the Beech, that of the Hornbeam appears to have been laterally squeezed, for the diameter taken one way is longer or shorter than if taken at right angles to the first measurement. Then again the leaf of Carpinns if placed upon that of Fagus will be found to be much less rotund in proportion to its length; the surface is rough, and instead of the cleanly cut margins of Fagus we have a coarse double-toothing.
The Hornbeam when full-grown is a much smaller tree than the Beech, rarely exceeding seventy feet in height, with a trunk circumference of ten feet; whereas the Beech reaches a height of considerably over a hundred feet, with a girth of nearly thirty feet. When naturally grown, too, it is by no means so picturesque as the Beech, but in places where it is most plentiful, as in Essex, especially Epping Forest, it is generally pollarded, and seldom allowed to exhibit its true form.
The male flowers form a pendulous catkin, originating in the axils, and each consisting of an egg-shaped bract, holding about a dozen stamens at its base. The female flowers form an erect flower-head, shaped like an artichoke at the end of a twig, the three-lobed bracts each containing two flowers. After fertilization these lobes enlarge considerably, and the flower-head lengthens into the pendulous string of fruits shown in our illustration. The flowers appear in May.