Slideshow image
Viburnum opulus var. americanum Aiton (redirected from: Viburnum trilobum)
Family: Adoxaceae
American cranberrybush,  more...
[Viburnum opulus var. trilobum (Marsh.) R.T. Clausen,  more]
Viburnum opulus var. americanum image
Shrub 1 - 5 m tall Leaves: opposite, stalked, 5 - 10 cm long, as wide or wider, three-lobed, maple-like, base rounded to truncate (cut straight across), lobes pointed, coarsely toothed, palmately veined, slightly hairy on the lower surface. Leaf stalks 1 - 3 cm long, with one to six large glands near the top. Glands stalked, mostly taller than wide, and round-topped. Flowers: in branched clusters (cymes). Cymes terminal, flat-topped, 5 - 10 cm wide, with large sterile flowers surrounding much smaller fertile flowers. Fertile flowers five-lobed, white, to 5 mm wide, tubular, sparsely hairy inside. Stamens five, exserted from the corolla. Filaments white. Anthers tan to yellow. Stigma three-lobed. Sterile flowers marginal, five-lobed, white, 1.5 - 2.5 cm wide, slightly irregular. Fruit: berry-like (drupe), in clusters, bright red, 10 - 15 mm wide, rounded, single-seeded. Twigs: stout, ribbed. Form: rounded.

Similar species: Another variety found in the Chicago Region, var. opulus, differs by having stalkless glands on the leaf stalks that are wider than tall and concave on top. Viburnum acerifolium and V. acerifolium var. ovatum are also similar but have slightly hairy branchlets, purplish black mature drupes, and dots on the leaf undersides.

Flowering: June to July

Habitat and ecology: Rare in rich woods, and has been seen in a bog.

Occurence in the Chicago region: native

Notes: About 200 species of Viburnum occur between North America, Europe and Asia. Many are ornamental shrubs cultivated for their showy flowers, autumn foliage, and attraction to wildlife.

Etymology: Viburnum is the Latin word for the Wayfaring tree. Opulus is the Latin word for a type of Maple. Americanum means "of the Americas" (North or South).

Author: The Morton Arboretum