Cornus

The genus Cornus is also known as the dogwoods[?], with over fifty species. Most species have opposite leaves. The fruit of all species is a drupe with one or two seeds. Flowers have four parts.

Cornus has been divided into various subgenera, with numbers ranging from four to nine or more. Four subgenera are enumerated here:

• With semi-showy flower clusters, usually white or whitish, in cymes, fruit blue to white:

• Mesomora, with alternate leaves
• Svida, with opposite leaves

• With inconspicuous flower clusters, usually greenish, surrounded by showy petal-like bracts, fruit usually red:

• Chamaeperi- clymenum, subshrubs growing from woody stolons
• Cynoxylon, shrubs and trees, including the flowering dogwood, Cornus florida

Many species in the Svida group are stoloniferous shrubs, growing along waterways. Several of these are used for naturalizing landscape plantings, especially the species with bright red or bright yellow stems.

Most of the species in the Cynoxylon group are small trees used as ornamentals. One, the Cornelian cherry, has edible fruit.

Eastern North American species of Cornus:

Mesomora

• Cornus alternifolia -- pagoda dogwood or alternate-leaved dogwood, most of eastern U.S. east of Great Plains, and extreme southeast Canada

Svida (Swida)

• Cornus amomum -- most of U.S. east of Great Plains except for deep south, and extreme southeast Canada
• Cornus drummondii -- rough-leaf dogwood, U.S. between the Appalachian belt and Great Plains, and southern Ontario
• Cornus racemosa -- northern swamp dogwood, extreme southeast Canada and northeast U.S.
• Cornus rugosa -- round-leaf dogwood, southeast Canada and extreme northeast U.S.
• Cornus stricta -- southern swamp dogwood, southeast U.S.

Chamaepericlymenum

• Cornus canadensis -- bunchberry, throughout Canada, into eastern Asia, and extreme northeast U.S.
• Cornus suecica -- Swedish cornel, eastern Canada

Cynoxylon

• Cornus florida -- U.S. east of the Great Plains into southern Ontario

Flowering dogwood, Cornus florida, in bloom

For a treatment of Asian dogwoods, see: http://hua.huh.harvard.edu/china/mss/volume14/Cornaceae-AGH_coauthoring.htm