- Name also: Guelder Rose, Rose Elder, Water Elder, Cramp Bark, High Bush Cranberry, High Cranberry, May Rose, King’s Crown, Silver Bells, Snowball Tree, European Cranberrybush, European Highbush (Canada)
- Family: Muskroot Family – Adoxaceae
(formerly Honeysuckle Family – Caprifoliaceae)
- Growing form and height: Shrub. 1–3 m (3–10 ft.).
- Flower: Inflorescence a flat-topped corymb, approx. 10 cm (4 in.) wide, consisting of two kinds of flower. Sterile outer flowers large, white, with 5 rounded perianth-segments. Inner flowers bisexual, white, bell-shaped. Stamens 5. Pistil formed from 3, fused carpels. Stigmas 3, styles absent.
- Leaves: Opposite. Exstipulate, stalked. Blade greyish and fine-hairy beneath, ca. 6 cm (2.4 in.) long, three-lobed, lobes taper-pointed, large-toothed.
- Buds: Egg-shaped, non-symmetrical, brownish green, glabrous, shiny. Buds opposite.
- Fruit: Red, single-seeded drupe.
- Habitat: Broadleaf woods, rich mixed swamps, streamsides. Also an ornamental.
- Flowering time: June–July.
The genus Viburnum comprises close to 150 species. Most of the species are native to the temperate regions of the Northern hemisphere. There are only three European species. Many ornamentals grown in Europe are originally North American. So is the case also with many species of Viburnum.
Guelder-rose is a shrub with angled stems and showy flowers, thriving best on damp, rich soils. The large, white outer flowers in the inflorescences have no stamens nor carpels, they only function as attractions for insects. The fertile central flowers are pollinated e.g. by bees and some beetles. Also self pollination takes place. The bark and wood of poisonous guelder-rose are fetid. The bark has been and still is used as a pain-alleviating medicine, That’s why the name ‘cramp bark’.