Filtered (75)
In the spring, American cranberry shrubs produce flattened panicles of flowers 2-5" across that bear two types of flowers — around the edges are five-petaled, white flowers about 1" across that are sterile (lacking both pistils and stamens), while in the center of the cluster are five-petaled, cream-colored flowers 1/4" across that are fertile (with both a pistil and five long stamens). By late summer, the flowers are replaced by bright red "cranberries" (actually drupes with a single seed) 1/4-1/2" across that prove very popular with birds (which distribute the seeds) and our local coyotes (whose scat is full of the seeds). After removing the seed, the tart flesh (high in vitamin C) can be eaten raw or cooked. In the fall, the leaves also turn red. Viburnum opulus var. americanum is said to be distinct from Viburnum trilobum (aka, highbush cranberry) by Illinois Wildflowers (www.illinoiswildflowers.info) and Minnesota Wildflowers (www.minnesotawildflowers.info), but plants.usda.gov insists that the latter is a synonym of the former. Worldfloraonline.org only adds to the confusion by insisting that the two names are BOTH junior synonyms of Viburnum opulus. ITIS.gov says that V. opulus is the correct name for the European species (now introduced to the U.S.) and Viburnum opulus var. americanum is the correct name for the American species. The easiest way to distinguish the two forms (if you care to) is to carefully inspect the nectary glands (extrafloral nectaries) on the petioles. In V. opulus americanum, the extrafloral nectaries are oval, with a concave top and a distinct rim; in Viburnum trilobum, the extrafloral nectaries are round in plan view with a convex top and no rim. Although rare in most of Illinois, guelder-rose (V. opulus americanum) is quite common around the lagoons of Jackson Park.

Viburnum

Viburnum opulus

American cranberry [Blooms: Apr-May]

Cymes of flowers arise from the leaf axils of blackhaw; the cymes are heavily branched but are sessile on the leaf axil. Individual flowers are 1/4" across with a 2 mm long calyx tube with five apical lobes that are shorter than the petals; a tubular corolla with five white, rounded lobes (the "petals"); five stamens with white filaments and yellow anthers extending outside the corolla lobes; and a small (less than 1 mm long), cream-colored pistil. The fruit is a fleshy drupe (like a plum or cherry) about 8 mm long containing a single brown nutlet that is flat on one side; the fruit becomes blue-black as it matures. The fruits are edible and popular with birds. Blackhaw is similar to nannyberry (Viburnum lentago, also found in Jackson Park) — both have white flowers and blue-black fruits that are drupes — but nannyberry leaves have a long, narrow tip on their leaves in contrast to the rather blunt tip and reddish petioles on blackhaw leaves. The stamens in blackhaw flowers are slightly shorter than those in nannyberry flowers but the difference is subtle; leaf form and petiole color are better differentiators.

Viburnum

Viburnum prunifolium

blackhaw [Blooms: May-June]

Many of the upper shoots of downy arrowwood end in 1.5-3" wide, dome-shaped panicles of flowers with slightly fuzzy, light green branches. Individual flowers are 1/4" across with a short, light green calyx with five short, broad teeth; a white tubular corolla with five rounded, spreading lobes; five stamens with white filaments and tan anthers that extend outside the corolla; and a single white style. The flowers have an unpleasant odor described by various sources as "rotting flesh." The fruit is a small (1/4-1/2") drupe (a stone fruit like cherries or a plum) 8 mm long and dark blue-violet to black at maturity. Downy arrowwood can be distinguished from other Viburnum spp. by its (1) its small size (less than six feet tall), (2) the relatively few teeth along the leaf margins (5-10 per side), (3) the short (about 1/4") leaf petioles, (4) the small, narrow stipules at the petiole bases, and (5) its flowers' unpleasant odor. The common name derives from the fact that the straight stems of the various arrowwoods was preferred by indigenous Americans for arrow shafts.

Viburnum

Viburnum rafinesquianum

downy arrowwood [Blooms: Aug–Sep]