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Scientific name: Anthophyta: Dicotyledonae: Sapindales: Aceraceae:
Common Name: Information Sheet, Eastern Flowering Dogwood

Country: USA
State/District: DC
County: not applicable
Date (D-M-Y): 5 - 2001

Photographer: E. M. Barrows

Identifier: E. M. Barrows
Collector: not applicable
Location: Rock Creek Park
Keywords: A FEtr Glover-Archbold green flower green fruit information sheet red fruit yellow flower
Additional Information:

Cornus florida Linnaeus (= Cynoxylon floridum (Linnaeus) Rafinesque) Eastern Flowering Dogwood (= Dogwood, Flowering Dogwood)

[Latin cronu, a horn, alluding to the hardness of the wood; florida, flowering]
[Old English dagge, a dagger or sharp pointed object; possibly alluding to hard daggers make from dogwood wood]
[The common name "Flowering Dogwood" refers to the large pink through white bracts of this species which surround small yellowish green flowers, making an entire inflorescence superficially look like one large flower.]
(Sutton & Sutton 1985, plates 52, 160, 190, 214; Petrides 1988, plate 14; Kricher & Morrison 1998, 53, 313, 411)

Range.   Eastern Flowering Dogwood is native to FL through TX and Mexico, north through southwest ME, southern NH, southern VT, NY, southern Ontario, OH, IN, AL, MO, and KS.   This species grows up to 12 m tall and commonly grows in forest edges and as an understory tree in forests.

Habit.   Tree, up to 50 ft tall, often 15–30 ft tall   Sometimes under 15 ft tall as a mature specimen.   Trunk, short, up to 1.5 ft across. Bark, with thin, squarish plates, looking like alligator hide.   Crown, spreading or nearly horizontal branches; covered with white bracts in spring; a very pretty tree in flower.   Flowers: April.   Fruit: green through red drupes.

General roles in forests.   Eastern Flowering Dogwood is an autotroph that generally live in forests, forest edges, successional areas, and yards.   Many kinds of organisms consume dead and living Eastern Flowering Dogwood fruits, leaves, roots, and stems.

Specific roles in forests.   Eastern Flowering Dogwood is a common successional tree and a common understory tree in many parts of the U.S. Dogwood (as a group) in the U.S. have these leaf, root, and stem feeders (parasites): 5 aphid spp., 1 bacterium sp., 1 beetle sp., 6 borer spp., 7 cicada spp., 31 fungus spp., 2 leafhopper spp., 1 mistletoe sp., 3 nematode spp., 2 virus kinds, 1 whitefly sp., and 1 weevil spp. (Horst 1990, 625).   Dogwood Anthracnose (a fungus) is a now a major Eastern Flowering Dogwood disease, and spot Anthracnose is a minor disease of this tree (Mitchell 1990, F2).   Deer and rabbits eat dogwood stems.   Nectar and pollen feeders (parasites, pollinators, predators) are many kinds of arthropods consume their nectar, pollen, or both; they include bee spp., the Honey Bee, beetle spp., flower-fly spp., other fly spp., and wasp spp.   Fruit feeders include Bobwhites, Eastern Gray Squirrels, Prairie Chickens, Ring-necked Pheasants, Ruffed Grouse, Sharp-tailed Grouse, other small mammal spp., many songbird spp., and Wild Turkeys (Farrar 1995).   In Bethesda, MD, Eastern Gray Squirrels pick the fruits off trees in August and September, split the ripening fruits, longitudinally, remove the seeds, and eat them (personal observation, 1996).

Identification by leaves. See Dicots: Ebenaceae: Common Persimmon.

Human uses.   We plant Eastern Flowering Dogwoods as ornamental shade trees.   In rural and urban areas, this species makes "white clouds" of bracts in April.   In fall, these trees have crimson leaves which are major autumnal beauty.   The showy cultivar Cornus florida 'Pluribracteata' has 6, or more, bracts per inflorescence.   We widely plant forms with pink through red bracts, as well as those with white bracts.   We have long used the wood of the European C. sanguinea for daggers and skewers.   We use the compact, dense, fine-grained, hard, strong, tough, and very heavy wood for chisel handles, engravers' and jewelers' blocks, golf-club heads, mallets, pulleys, roller skate wheels, other turned articles (turnery), tool handles, weaving shuttles, wheel hubs (Brown 1921, 299; Stephens 1969, 201).

Comments.   Eastern Flowering Dogwood is the state tree of Massachusetts and Virginia and the state flower of North Carolina.

Wood.   Xylem: close grained, hard, heavy, light, reddish brown, strong.   Phloem: lighter colored than xylem, thick.

Dogwood Anthracnose (DA)
      Dogwood Anthracnose began killing Eastern Flowering Dogwoods the Washington, D.C., Area in the 1980s.   Researchers first discovered DA on Long Island, NY, in 1978 (Fenyvesi 1991, 22).   In the 1980s, DA killed huge stands of Eastern Flowering Dogwoods in natural woodlands from Maine through Georgia.   Researchers found the disease in Rock Creek Park in 1990.   Dogwood Anthracnose killed many beautiful Eastern Flowering Dogwoods in national parks and elsewhere.
      An Eastern Flowering Dogwood that is dying from DA first has spots (tan with dark purple borders) on its leaves (Fenyvesi 1991, 22).   Then its leaves become blighted, droop, and drop, and the twigs and limbs wither.   Water sprouts (which are tiny spots) appear on its trunk, followed by cankers.   Finally the tree dies.   Rain and wind carry the spores to other trees.   An infected tree shows leaf dieback that first occurs in its lower crown and moves up the tree (Mielke and Daughtrey 1989, Weaver and Smith 1999, Hansen 2000).   Leaves develop tan spots with purple borders or tan blotches which often expand Dogwood Anthracnose DA infection moves from the leaves to the twigs.   Cankers develop from leaf nodes and cause twig dieback.   Dead twigs are tan and are often covered with tiny black fungal fruiting bodies (called conidiomata) which produce masses of orange spores during wet weather.   A tree may grow water sprouts (succulent shoots) on its as after twig dieback.   The fungus spreads from the twigs to the main branches, and multiple cankers coalescing and girdle individual branches. The fungus can kill a tree in 2–3 years.
      Control.   Plant resistant trees (Fenyvesi 1991, 22).   At least two trees in the Catoctin Mountains escaped DA attack.   They might be resistant.   Many urban trees have remained uninfected, and might also be resistant.   Some trees in Silver Spring and on Long Island have been infected as long as 10 years and remained prosperous.
      The fungicides Benomyl, Bravo, Chlorothalonil, Daconil, and Mancozeb prevent infection.   Researchers are working on improved, new fungicides.   Heat waves slow down the fungus which is not active at temperatures above 75 degrees.
      The Asian Dogwood, Cornus kousa, is DA resistant but not immune (Mitchell 1990, F2).   Hybrids between C. florida and C. kousa might result in resistant trees that resemble our native Eastern Flowering Dogwood.

Fenyvesi, C.   1991.   Hope for the Dogwood.   Washington Post Home 27 June 1991: 22.

Mitchell, H.   1990.   The demise of the Dogwood.   Washington Post 8 April 1990: F2.

E.M.B. (2002)

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