The genus Cornus is also known as the dogwoods, with about 30-50 species depending on taxonomic interpretation. Most species have opposite leaves, but alternate in a few. 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 red, blue or white:

• Subgenus Cornus: flower clusters with a deciduous involucre
• Subgenus Swida: flower clusters without an involucre

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

• Subgenus Chamaepericlymenum: subshrubs growing from woody stolons
• Subgenus Benthamidia (Cynoxylon): shrubs and trees, including the flowering dogwood, Cornus florida

Many species in the Swida 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 Benthamidia group are small trees used as ornamentals.

Eastern North American species of Cornus:

• Subgenus Swida
  • Cornus alternifolia -- Alternate-leaved Dogwood or Pagoda Dogwood; most of eastern U.S. east of the Great Plains, and extreme southeast Canada
  • Cornus amomum -- most of U.S. east of the Great Plains except for deep south, and extreme southeast Canada
  • Cornus drummondii -- Rough-leaf Dogwood; U.S. between the Appalachian belt and the 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.
• Subgenus Chamaepericlymenum
  • Cornus canadensis -- Dwarf Cornel or Bunchberry; throughout Canada, into eastern Asia, and extreme northeast U.S.
  • Cornus suecica -- Swedish Cornel; eastern Canada
• Subgenus Benthamidia (Cynoxylon)
  • Cornus florida -- Flowering Dogwood; 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

Common dogwood flowering (Cornus sanguinea)

Species list

• Subgenus Cornus
  • Cornus mas - European Cornel
  • Cornus chinensis - Chinese Cornel
  • Cornus officinalis - Japanese Cornel
  • Cornus sessilis - Blackfruit Cornel
• Subgenus Swida
  • Cornus alba - Tatarian Dogwood
  • Cornus alternifolia - Alternate-leaf Dogwood
  • Cornus austrosinensis
  • Cornus amomum - Silky Dogwood
  • Cornus asperifolia - Rough-leaf Dogwood
  • Cornus bretschneider
  • Cornus controversa - Table Dogwood
  • Cornus coreana
  • Cornus drummondii - Rough-leaf Dogwood
  • Cornus foemina - Swamp Dogwood
  • Cornus hemsleyi
  • Cornus koehneana
  • Cornus macrophylla - Bigleaf Dogwood
  • Cornus obliqua - Pale Dogwood
  • Cornus oligophlebia
  • Cornus papillosa
  • Cornus parviflora
  • Cornus quinquenervis
  • Cornus racemosa - Northern Swamp Dogwood
  • Cornus rugosa - Round-leaf Dogwood
  • Cornus sanguinea - Common Dogwood
  • Cornus schindleri
  • Cornus sericea - Redtwig Dogwood
  • Cornus stricta - Southern Swamp Dogwood
  • Cornus ulotricha
  • Cornus walteri - Walter Dogwood
  • Cornus wilsoniana
• Subgenus Chamaepericlymenum
  • Cornus canadensis - Dwarf Cornel or Bunchberry
  • Cornus glabrata
  • Cornus sessilis
  • Cornus suecica - Swedish Cornel
  • Cornus unalaschkensis
• Subgenus Benthamidia (Cynoxylon)
  • Cornus angustata
  • Cornus capitata - Himalayan Flowering Dogwood
  • Cornus florida - Flowering Dogwood
  • Cornus hongkongensis
  • Cornus kousa - Kousa Dogwood
  • Cornus multinervosa
  • Cornus nuttallii - Pacific Dogwood
  • Cornus urbaniana - Mexican Flowering Dogwood

Cornus is also the name of a commune in the Aveyron département, in France