Dogwood family (Cornaceae)
Description: This native shrub is 3-9' tall (rarely taller), developing multiple ascending stems from the ground. The basal stems branch outward toward along the upper portion of each shrub. The mature stems become woody; their bark is smooth, dark red, hairless, and shiny (less often it is yellow or brown). The bark is often covered with numerous white lenticels (air pores). Pairs of opposite leaves develop along the new growth of the stems. The leaf blades are 2-4" long and 1-3" across; they are ovate-lanceolate to ovate in shape and smooth along their margins. The upper surfaces of the leaf blades are medium green and hairless, while their lower surfaces are pale green. Depending on the local ecotype or variety, fine pubescence is sometimes present along the lower surfaces of the leaf blades.
Flat-headed panicles (or cymes) of white flowers occur among the leaves. These panicles span about 2-3" across. Individual flowers are ¼" across, consisting of a small green calyx with 4 narrow teeth, 4 white petals, 4 stamens, and a pistil with a single style. The petals are narrowly lanceolate and spread outward from the center of each flower. The blooming period occurs from late spring to early summer and sometimes later in the year. The flowers are fragrant. After the blooming period, the flowers are replaced by globoid drupes (one-seeded berries) up to 1/3" across that become white at maturity. Each fleshy drupe contains a single large seed. The drupes are mildly bitter and sour. The woody root system is branching and shallow. Vegetative offsets are often produced from either underground runners or above ground stolons, resulting in colonies of shrubs.
Cultivation: The preference is full sun to partial shade, moist conditions, and soil that is loamy, silty, or sandy. This shrub develops fairly quickly and tolerates temporary flooding. It should not be located at sites that are hot and dry.
Range & Habitat: Red-Osier Dogwood is occasional in the northern half of Illinois, while in the southern half of the state it is uncommon. It tends to be more common in sandy areas than non-sandy areas. Habitats include moist sandy thickets, shrub swamps, shrubby bogs, sandy areas along rivers, fens, interdunal swales, marshes, and sandy ditches. This shrub is often used as a landscaping plant and there are many cultivars available.
Faunal Associations: The nectar and pollen of the flowers attract many kinds of insects, including long-tongued bees, short-tongued bees, wasps, flies, and butterflies. The short-tongued bee, Andrena fragilis, is an oligolectic visitor (specialist pollinator) of Cornus spp. (Dogwood shrubs). Other insects feed on the leaves, suck plant juices, or bore through the wood. These species include the caterpillars of many moths (see Moth Table), long-horned beetles (Cerambycidae), leaf beetles (Chrysomelidae), aphids (Aphididae), plant bugs (Miridae), and others (see Insect Table). Because of their higher than average fat content, the white drupes of Red-Osier Dogwood are an important food source of wood ducks, songbirds, and upland gamebirds (see Bird Table). The White-Footed Mouse and other small rodents also eat the drupes. The White-Tailed Deer and Cottontail Rabbit browse on the leaves and woody stems; beavers also use the stems as a food source and as construction material for their dams and lodges. To a minor extent, the fallen leaves are eaten by some turtles, including Chelydra serpentina (Snapping Turtle) and Trachemys scripta (Slider).
Photographic Location: On the grounds of the Independent Media Center in Urbana, Illinois.
Comments: Because of its attractive woody stems, Red-Osier Dogwood is one of the more attractive Cornus spp. (Dogwood shrubs), particularly during the winter. Because of these showy stems, it is fairly easy to identify. Other Dogwood shrubs with white berries include Cornus racemosa (Gray Dogwood) and Cornus drummondii (Rough-Leaved Dogwood). Gray Dogwood has gray or brown twigs, while the young shoots and leaves of Rough-Leaved Dogwood are more hairy than those of Red-Osier Dogwood. There is a variety of Red-Osier Dogwood, var. baileyi, that is found in the sand dune region along Lake Michigan. In contrast to the typical variety (described above), this variety has leaf undersides with appressed pubescence and its stems are more brown. A scientific synonym of Red-Osier Dogwood is Cornus stolonifera.