Plants of the Eloise Butler Wildflower Garden

The Viburnums are shrubs of woodlands and moist woodland borders. The Highbush Cranberry is a native tall shrub, reaching to 15 feet in height, with arching multiple stems.

Twigs are a light reddish brown and have opposite buds with reddish- brown scales.

Bark on older stems becomes gray and scaly.

The leaves are opposite, simple three lobed and with course teeth and 1 to 6 small glands, on short stalks, near the base of the blade on the grooved reddish-brown stalk. The leaves are green during the summer and turn to a nice purplish-red in Autumn. The undersides are hairy. There is a pair of slender stipules where the stalk attaches to the stem, but these drop away early. The groove on the stalk is wide and flat-bottomed.

The inflorescence consists of flat-topped clusters of stalked flowers (a cyme), each cluster up to 3 to 4 inches wide, on the tips on new growth.

The flowers are of two types - an outer ring of florets that are particularly showy and noticeable. These are sterile, whereas the inner cluster of small florets are fertile. The corollas are white, 5-parted. The outer florets have corollas with 5 spreading rounded lobes, a short green calyx with 5 pointed lobes. The inner florets are similar in shape but only 1/4 inch wide. These have the reproductive parts of 5 stamens that have white filaments and creamy colored anthers and which are exserted from the corolla. These are spreading and placed alternate to the petals. The pistil and ovary lack a style.

Eloise Butler wrote of the flowers: Dame Nature, who practices economy when she can, had intended the neutrals for guide boards to insects that, in getting the food prepared for them in the numerous small perfect flowers, would do service in turn, by insuring fruit for birds and humans.["Shrubs in the Wild Garden" - 1926]

Fruit: After flowering in May the fruit forms and gradually changes color from green to the deep red of Autumn. Each drupe is about 1/3 inch across and contains one flattened 5mm wide seed. The fruit is acidic but edible off the plant and when properly prepared makes a good preserve.

Habitat: Highbush Cranberry prefers the consistently moist soils of low places as long as the soil is loamy with drainage, and it needs plenty of sun to flower and fruit sufficiently. Pruning is best done immediately after flowering. The majority of these shrubs in the Woodland Garden of Eloise Butler are found near the wetland pool, are quite old and produce quantities of berries.

Names: In the never ending quest for specificity, botanists have recently moved the Viburnum genus into the Adoxaceae plant family, which is a small group of 5 genera of shrubs that have opposite leaves, mostly 5-petaled flowers that produce a small drupe. Minnesota authorities have made this change, USDA has not yet. Botanists have also recently reclassified the species of this plant from the old Viburnum trilobum to a variety with the name Viburnum opulus var. americanum. Interestingly, in Eloise Butler's time the plant was known as V. opulus var. americanum. The genus name, Viburnum, covers a large number of shrubs and the name is an old Latin name for one particular member of the genus. The species opulus, is taken directly from the Greek where it referred to a type of maple and was applied here due to the maple-like leaf shape. The author name for the plant classification, ‘Aiton’ is for William Aiton (1731-1793), Scottish botanist, who succeeded Philip Miller as superintendent of the Chelsea Physic Garden and then became director of Kew Gardens, where he published Hortus Kewensis, the Garden’s catalogue of plants.

Comparisons: While there are other Viburnums in Minnesota as denoted below, the one closely resembling this species is the introduced European Cranberrybush, V. opulus var. opulus. The European variety grows in more upland sites but does hybridize with the American variety. The tiny glands on the leaf stalk are usually sessile. The groove on the leaf stalk is narrow with a v-shaped bottom. A fairly complete review of both species is found in this Technical Conservation Assessment (pdf) from the USDA Forest Service.