flowering dogwood, Cornus florida
Scientific Name
Cornus is from the word cornu which means “horn” and refers to the hard wood; florida is from the Latin flos, which means “flower” or “flowery” in reference to the showy flowers.
Common Name
Flowering dogwood is named for the showy spring flowers. The common name dogwood comes from one colonial description of the fruit as being edible but not fit for a dog. The common name dogwood is also thought to be from the use of the wood for skewers or “dogs.” Other common names include boxwood and cornel.
NATIVE RANGE AND HABITAT
Flowering dogwood trees can be found from Toronto south to the Gulf Coast and from southern Maine to eastern Texas. Trees grow in the understory on lower and middle slopes. Flowering dogwood occurs frequently across Kentucky in dry to wet woods.
CONSERVATION INFORMATION
Flowering dogwood is seriously threatened by dogwood anthracnose which is caused by a fungus. The disease is spreading rapidly throughout the species’ range. Trees are typically killed in 2 to 3 years. The fungus requires high humidity for infection, so trees growing on moist, shady sites are most susceptible.
Silky dogwood is not ranked as a plant of conservation concern by the Kentucky State Nature Preserves Commission. It is listed on the Threatened and Endangered Species List in both Maine and Vermont.
Growth Habit and Form
Flowering dogwood is a small, showy, deciduous tree. Trees typically grow 20 feet tall. Young trees tend to be upright to rounded and mature specimens growing up to 50 percent wider than tall. The crown is round to flat-topped. The lateral branches are somewhat horizontal and form a recognizable feature in the winter landscape.
Leaves
The opposite leaves are simple, oval to ovate, 3 to 6 inches long and half as wide with smooth edges. Summer leaves are bright green above and lighter on the underside. Fall color can be a spectacular scarlet to purplish.
Flowers
The small flower clusters are surrounded by four, showy, petal-like bracts that turn white as they expand. On some cultivated varieties bract color is creamy, pink to nearly red. True flowers are greenish yellow. Total width of each floral display ranges from 3 to 5 inches across. Flowers bloom in early spring before the leaves emerge.
Fruit is a brilliant red, shiny, oval drupe that is ½ inch long, borne in groups of as few as 1 or 2 and as many as 10 or more. Fruit ripen between September and October and the red coloration complements the fall foliage. Some fruits remain on the plant into winter.
Bark
First year stems are purple to reddish green, turning gray by year two. Older branches and trunks develop a blocky pattern of gray to reddish-brown. The wood is extremely dense but highly susceptible to decay.
Wild and Cultivated Varieties
Cultivated varieties of flowering dogwood are typically divided into groups based on certain characteristics: large flowers, pink flowers, red flowers, fragrant flowers, double flowers, heavy blooming, variegated leaves, dwarf form, or weeping form. Over 100 varieties are recognized by authorities. More commonly available selections include the following.
‘Cherokee Chief’ has ruby, red bracts and is one of the most poplar red-bract dogwoods.
‘First Lady’ has yellow and green variegated leaves and white flowers. Variegation is temperature sensitive.
‘Fragrant Cloud’ is a prolific white flowering tree. The flowers are lightly scented.
‘Poinsett’ has a compact form and yellow fall berries. The cultivar was introduced by Pete Girard of Geneva, Ohio.
‘Royal Red’ has deep red spring and fall foliage. The flowers are red and very large.
‘Sweetwater Red’ has deep red flowers. The foliage is reddish throughout the growing season, turning reddish-purple in autumn. The cultivar was selected by the Howell Nursery in Tennessee in 1954.
HORTICULTURE
Landscape Use
Flowering dogwood is a spectacular flowering tree native to our region and one of the most popular small ornamental trees in America. Flowering dogwood has been named the state tree of both Virginia and Missouri, and the state flower of North Carolina. It is a plant with four-season character – showy spring flowers, summer and fall foliage, fall fruit and winter branching habit. Trees can be used in groupings, as specimens or in naturalized areas. The average lifespan is 80 years.
Hardiness Zone
Flowering dogwood is rated hardy in USDA Zones 5 to 9.
Growth Rate
The growth rate is slow upon transplanting, gradually assuming a medium rate.
Cultivation and Propagation Information
Plant flowering dogwood grown from seed collected from trees indigenous to your local area. Dogwood grows best in deep, moist soils and in full sun or partial shade. Trees grow easily from seed but are not easily transplanted. Clean seed that has been cold stratified for 90-120 days germinates near 100 percent. Transplant balled-and-burlapped or container-grown plants in the spring. Flowering dogwood was introduced into cultivation in the 1730s. George Washington and Thomas Jefferson reportedly planted dogwoods around their estates and gardens.
Diseases and Insects
Trees are susceptible to anthracnose, dogwood borer and powdery mildew. Flowering dogwood is seriously threatened by dogwood anthracnose which is caused by a fungus. The disease first became a problem around 1980 and is spreading rapidly throughout the trees’ range. Trees are typically killed in 2 to 3 years. The fungus requires high humidity for infection, so trees growing on moist, shady sites are most susceptible. Dogwood borer (Synanthedon scitula) is a clearwing moth that is attracted to weakened trees, pruning cuts, and sunscald-damaged bark areas.
Wildlife Considerations
The fruits are eaten by migrating birds and are an important food for overwintering birds such as bluebirds. Fruit is also eaten by ruffed grouse, quail, black bear, deer, chipmunks, skunks and squirrels. The fruits, flowers, twigs, bark and leaves are eaten by a variety of wildlife.
Maintenance Practices
Good cultural practices translate to healthy trees. Hearty, well-maintained flowering dogwood trees in sunny areas with good air circulation and proper soil moisture are rarely impacted by anthracnose. Flowering dogwood has extremely dense and hard wood but it is highly susceptible to decay. Bark damage of any kind heals very slowly and flowering dogwood does not tolerate heavy pruning.
TRADITIONAL AND MODERN USES
The hard wood was used to make weaving shuttles and golf club heads. The wood is used for specialty products such as spools and jewelry boxes.
Root, stem and twig bark was used as a native substitute for quinine.
Native Americans made an infusion from the flowers for fevers and colic. Flowering dogwood is an important ornamental tree.