Family: Cornaceae (dogwood family)
Common Names: dogwood, flowering dogwood
Description
The graceful yet compact shape and brilliant springtime blooms make this a favorite landscape tree throughout its range. The flowering dogwood is just about the finest flowering tree you can find. It is beautiful in all seasons and even though it is nearly ubiquitous in home landscapes, it never seems to be overplanted.
Flowering dogwood is a small tree, up to 30 ft (9 m) in height and 35 ft (10.7 m) across, but the typical size is more like 15 ft (4.6 m) tall and 15-20 ft (4.6-6 m) across. It has a short trunk and a full, rounded crown with horizontal branches often in layered tiers, spreading wider than its height. The bark on mature trees is broken up into small square blocks. Flowering dogwood has opposite, deciduous midgreen leaves, 3-6 in (7.6-15 cm) long, which turn red and purple in autumn. Flowering dogwood blooms in the spring, as its new leaves are unfolding, and usually remains showy for 2-3 weeks.
The inflorescence consists of four showy petal-like bracts, usually snow white or pink, surrounding a cluster of tiny inconspicuous yellowish flowers. The bracts are 1-2 in (2.5-5 cm) long and obovate in shape, usually with a cleft at the tip. Clusters of bright red football shaped fruits, about a half inch long, follow the flowers and often persist into winter.
It grows in a variety of habitats throughout its range, but generally occurs on fertile, well drained but moist sites. Flowering dogwood is usually an understory component in mixed hardwood forests or at the edges of pine forests.
Culture
Light: Partial or broken shade is best, but flowering dogwood can tolerate full sun, too. It does best with some shade in the south and full sun in the north.
Moisture: Established specimens are tolerant of normal dry periods, but will need supplemental watering during extreme droughts. Stress of any kind makes dogwoods susceptible to diseases.
Propagation
Propagate dogwood from greenwood cuttings in spring, hardwood cuttings in summer, or from seed. Cultivars are usually bud grafted onto seedling rootstock.
Pests and diseases
In recent years, flowering dogwood has been severely impacted by dogwood blight, a fungus disease that can decimate natural populations. The disease was first discovered in the 1970's, and by the 90's it had spread throughout most of the dogwood's range. Infected trees show small spots with purple margins on the leaves. The disease eventually kills the leaves, and in 2-3 years the tree dies. The disease (an anthracnose in the genus Discula) thrives in cool, moist weather. Dogwoods in the open, with good air circulation and sunlight, are not usually attacked as are trees in the forest understory.
Several other diseases (powdery mildew, cankers, phytophthora leaf blight, etc.) attack flowering dogwood, especially in wet weather, but, although unsightly, they are rarely fatal. Twig borers often infest flowering dogwood, killing the tips of young twigs.
Varieties
Hundreds of selections have been named. 'Cherokee Chief' has dark pink bracts. 'Cloud Nine' has large bracts which overlap each other. 'First Lady' has yellow variegated leaves. 'Plena' has 7 or 8 bracts instead of four. 'Nana' is a dwarf, to 6 ft (m) tall. 'Pendula' has weeping branches.