Cornus alba

American, or red osier dogwood is sometimes considered to be a subspecies, but sometimes as a species in its own right. It is a little lower and less stiffly growing than Tatarian dogwood (C. alba subsp. alba) and spreads faster to form typical dogwood thickets.

American dogwood produces white flowers in June, with decorative pale blue or white berries in autumn. New shoots are green in spring but later change to red; older shoots turn pale brown and the bark splits. Removal of old growth helps to keep the shrub colourful.

All the shrubby dogwoods have rich foliage and a dense habit, while their stems add colour to the winter scene. In the garden they look best against a light or dark background, against a wall or large rock, for example. Many of the dogwood varieties are in fact grown specifically for their colourful stems. The variety ‘Flaviramea’, so common in Finnish gardens, has yellow stems.

The Native North Americans used American dogwood in their medication, dyes were made from the bark, and they wove baskets from the stems.

Cornus was what the Romans called the red-berried Cornelian cherry (C. mas), which grows into a small tree. The word cornus also means horn and may be a reference to the strong and durable timber. Nowadays the genus Cornus includes two herbaceous and about 40 woody species, mainly in Eurasia and North America.

This subspecies of Siberian dogwood is a broad shrub whose lower branches often touch the ground, when they can root. The inflorescences are white, and produce round, remarkably white berries, sometimes with a bluish tint. The colours of foliage and stems vary and the most colourful forms are sold as nursery varieties. The most popular in Finland has been the so-called “coral dogwood” (C. alba ‘Sibirica’), whose stems are a very strong red when grown in full light, even in winter.

American dogwood (C. alba subsp. stolonifera) differs from the eastern subspecies in the shape of its narrower leaves, slightly earlier flowering, rounder white berries and abundant root suckers.