The Dogwoods comprise a group of 30-50 species of mostly deciduous woody plants growing as shrubs and trees, some species are herbaceous perennial plants and a few of the woody species are evergreen. They are in the family Cornaceae, divided into one to nine genera or subgenera (depending on botanical interpretation). Four subgenera are enumerated here.
Many species in subgenus Swida are stoloniferous shrubs, growing along waterways. Several of these are used in naturalizing landscape plantings, especially the species with bright red or bright yellow stems. Most of the species in subgenus Benthamidia are small trees used as ornamental plants. As flowering trees, they are of rare elegance and beauty, comparable to Carolina silverbell, Canadian serviceberry, and the Eastern Redbud for their ornamental qualities.
The fruit of several species in the subgenera Cornus and Benthamidia is edible, though without much flavour. The berries of those in subgenus Swida are mildly toxic to people, though readily eaten by birds. Dogwoods are used as food plants by the larvae of some Lepidoptera species including Emperor Moth, The Engrailed, Small Angle Shades and the following case-bearers of the genus Coleophora: C. ahenella, C. salicivorella (recorded on Cornus canadensis), C. albiantennaella, C. cornella and C. cornivorella (The latter three feed exclusively on Cornus). They were used by pioneers to brush their teeth. The pioneers would peel off the bark, bite the twig and then scrub their teeth.
The inflorescence of Pacific Dogwood is the official flower of the province of British Columbia
The Dogwood (Cornus florida) and its inflorescence are the state tree and the state flower respectively for the U.S. Commonwealth of Virginia. It is also the state tree of Missouri and the state flower of North Carolina.
Larger items were also made of dogwood such as the screw in basket-style wine or fruit presses, also made were the first styles of the tennis racket made out of the bark cut in thin strips.
Another earlier name of the dogwood in English is the whipple-tree. Geoffrey Chaucer uses the word whippletree in the Canterbury Tales (The Knight's Tale, verse 2065) to refer to the dogwood. Another larger item made of dogwood still bears the name of the tree from which it is carved. The whippletree is an element of the traction of a horse-drawn cart, which links the drawpole of the cart to the harnesses of the horses in file.
The name Dog-Tree entered English vocabulary by 1548, and had been further transformed to Dogwood by 1614. Once the name dogwood was affixed to the tree, it soon acquired a secondary name as the Hound's Tree, while the fruits came to be known as dogberries or houndberries (the latter a name also for the berries of Black nightshade & alluding to Hecate's hounds).
It is possible that the common name of Dogwood may have come because “dogs were washed with a brew of its bark, hence Dogwood.” Another name is blood-twig, due to the red colour it turns in autumn.
In botany and in colloquial use, the term dogwood winter may be used to describe a cold snap in spring.