Viburnum, an ancient name of a genus of monopetalous shrubs or small trees of the honeysuckle family (caprifoliaceoe), in which there are about 80 species; the majority are natives of North and South America, a few being found in Europe and Asia. The viburnums have opposite and simple leaves, and small white flowers in terminal, flat, compound cymes; the very minute flowers consist of a calyx, the tube of which is coherent with the ovary and fivetoothed, a deeply five-lobed spreading corolla, and five stamens; the one- to three-celled ovary is surmounted by a short three-lobed style, and ripens into a one-celled, one-seeded drupe, containing a single flattened stone.
There are about a dozen species in the United States, some of which, in the northern portions at least, form a considerable part of the coppice and undergrowth of woods. In two of our species the flowers upon the margin of the cyme are sterile and their corollas are greatly enlarged, forming a showy border to the cluster; a garden form of one of these, V. opulus (also a native of Europe), has all of the flowers sterile and showy. (See Guelder Rose.) The other species with sterile flowers is called hobble-bush, for the reason that its straggling reclining branches take root where they touch the ground, and impede the traveller; it is found in cold woods from New England to Pennsylvania, and further south along the mountains; its round-ovate leaves are heart-shaped at base, serrate, 4 to 8 in. across, with the veins and stalk covered with a rusty scurf; the heads of flowers are broad and showy, and the crimscm fruit is not edible. This species is named V. lantanoides from its resemblance in leaves, though not in flowers, to V. lantana of Europe, which is there called the wayfaring tree on account of its frequent occurrence on the roadside; and our shrub is sometimes called the American wayfaring tree.
Of the remaining species, without the conspicuous sterile flowers, the following deserve a special mention. The sweet viburnum, or sheep berry ( V. lentago), is one of the most frequent northern species; it has ovate, strongly pointed, very sharply serrate leaves, with margined petioles; the flower clusters are terminal and axillary, appearing in great abundance in May and June, and have a pleasant fragrance; the oval fruit, shining blue-black, half an inch or more long, is showy, sweet, and edible. This is one of our most beautiful shrubs, and when unmutilated (for cattle are fond of browsing on it) is sometimes a tree 20 to 30 ft. high. It has been successfully used to form an ornamental hedge. Arrowwood is the common name for another abundant species ( V. dentatum), which is widely distributed; it sometimes reaches 15 ft., but is usually only 5 or 8 ft. high; its leaves, from half an inch to an inch long, have very large and sharp teeth and strong veins; the fruit is bright blue. The mapleleaved viburnum (V. acerifolium), which in some parts of the country is called dockmackie, rarely grows above 6 ft., and may be readily mistaken when not in flower for a young maple sapling; its three-ribbed and three-lobed leaves are from 2 to 4 in. long and broad, and irregularly toothed on the margin; the fruit, at first crimson, turns to blackish purple and is inedible; it is very common in rocky woods.
The most important exotic species is V. tinus, which is not rare as a house plant under the name of laurestinus; it is a native of southern Europe; it has evergreen leaves and clusters of flowers which are rose-colored in the bud, but white when open; it continues long in flower, and is much valued for the house and for decoration.
Maple-leaved Viburnum (V. acerifolium).
Laurestinus (Viburnum tinus).