Cornus florida | |
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Flowering dogwood in Spring | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Cornales |
Family: | Cornaceae |
Genus: | Cornus |
Subgenus: | Cornus subg. Cynoxylon |
Species: | C. florida |
Binomial name | |
Cornus florida | |
Natural range of Cornus florida | |
Synonyms [3] | |
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Cornus florida, the flowering dogwood, is a species of flowering tree in the family Cornaceae native to eastern North America and northern Mexico. An endemic population once spanned from southernmost coastal Maine south to northern Florida and west to the Mississippi River. [4] The tree is commonly planted as an ornamental in residential and public areas because of its showy bracts and interesting bark structure.
The flowering dogwood is usually included in the dogwood genus Cornus as Cornus florida L., although it is sometimes treated in a separate genus as Benthamidia florida (L.) Spach. Less common names for C. florida include American dogwood, Florida dogwood, Indian arrowwood, Cornelian tree, white cornel, white dogwood, false box, and false boxwood.
Two subspecies are generally recognized:
Image | Scientific name | Distribution |
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Cornus florida subsp. florida | eastern + south-central United States. | |
Cornus florida subsp. urbiniana (Rose) Rickett | northeastern Mexico (Nuevo León, Veracruz). | |
This section needs additional citations for verification .(September 2023) |
Flowering dogwood is a small deciduous tree growing to 10 m (33 ft) high, often wider than it is tall when mature, with a trunk diameter of up to 30 cm (1 ft). A 10-year-old tree will stand about 5 m (16 ft) tall. The leaves are opposite, simple, ovate, 6–13 cm (2.4–5.1 in) long and 4–6 cm (1.6–2.4 in) broad, with an apparently entire margin (actually very finely toothed, under a lens); they turn a rich red-brown in fall.
Flowering dogwood attains its greatest size and growth potential in the Upper South, sometimes up to 40 feet in height. At the northern end of its range, heights of 30–33 feet are more typical. Hot, humid summer weather is necessary for new growth to harden off in the fall.
The maximum lifespan of C. florida is about 80 years. [5]
The flowers are individually small, inconspicuous, and hermaphroditic, with four, greenish-yellow petals (not bracts) 4 mm (0.16 in) long. Around 20 flowers are produced in a dense, rounded, umbel-shaped inflorescence, or flower-head, 1–2 cm (0.39–0.79 in) in diameter. The flower-head is surrounded by four conspicuous large white, pink or red bracts (not petals), each bract 3 cm (1.2 in) long and 2.5 cm (0.98 in) broad, rounded, and often with a distinct notch at the apex.
When in the wild they can typically be found at the forest edge and frequently on dry ridges. While most of the wild trees have white bracts, some selected cultivars of this tree also have pink bracts, some even almost a true red. They typically flower in early April in the southern part of their range, to late April or early May in northern and high altitude areas. The similar Kousa dogwood ( Cornus kousa ), native to Asia, flowers about a month later.
The fruit is a cluster of two to ten separate drupes, (fused in Cornus kousa), each 10–15 mm (0.39–0.59 in) long and about 8 mm (0.31 in) wide, which ripen in the late summer and the early fall to a bright red, or occasionally yellow with a rosy blush. They are an important food source for dozens of species of birds, which then distribute the seeds. They are also a larval host plant for several moth varieties, including Eudeilinia herminiata , the dogwood thyatirid moth, Antispila cornifoliella , the stinging rose moth, the grand arches moth, [6] the pecan bark borer, [7] the dogwood borer, [8] the rosaceous leaf roller, the diamondback epinotia moth, spring azures, [9] cecropia moths, [9] and the Io moth. While not poisonous to humans, the fruit is extremely sour and unpleasant-tasting.[ citation needed ] Flowering dogwood is monoecious, meaning the tree has both male and female flowers, and all trees will produce fruit.
Flowering dogwood does best horticulturally in moist, acidic soil in a site with some afternoon shade, but good morning sun. It does not do well when exposed to intense heat sources such as adjacent parking lots or air conditioning compressors. It also has a low salinity tolerance. The hardiness zone is 5–9 and the preferred pH is between 6.0 and 7.0. [10] In urban and suburban settings, care should be taken not to inflict mower damage on the trunk or roots, as this increases the tree's susceptibility to disease and pest pressure. [10] : 98–100 The common flowering dogwood has been placed on the endangered species list in Ontario. [11] [12] [13] Sites should be selected for reasonably well-drained, fertile soils; full sun is recommended in high-hazard areas (such as stream or pond banks). New plantings should be mulched to a depth of 5 to 10 cm (2 to 4 in), avoiding the stem. Dead wood and leaves should be pruned and completely removed and destroyed yearly. Plants should be watered weekly during droughts, with watering done in the morning, avoiding wetting the foliage. Registered fungicides can be applied when necessary, according to manufacturers instructions and advice of local Extension Service. [14]
Flowering dogwood is grown widely throughout the temperate world.
Cornus florida is easily propagated by seeds, which are sown in the fall into prepared rows of sawdust or sand, and emerge in the spring. Germination rates for good clean seed should be near 100% if seed dormancy is first overcome by cold stratification treatments for 90 to 120 days at 4 °C (39 °F). [10] : 100–102 [17] Flowering dogwood demonstrates gametophytic self-incompatibility, meaning that the plants can't self-fertilize. This is important for breeding programs as it means that it is not necessary to emasculate (remove the anthers from) C. florida flowers before making controlled cross-pollinations. These pollinations should be repeated every other day, as the flowers must be cross-pollinated within one or two days of opening for pollinations to be effective. [18]
Softwood cuttings taken in late spring or early summer from new growth can be rooted under mist if treated with 8,000 to 10,000 ppm indole-3-butyric acid (IBA). In cold climates, potted cuttings must be kept in heated cold frames or polyhouses the following winter to maintain temperatures between 0 and 7 °C (32 and 45 °F). Although rooting success can be as high as 50–85%, this technique is not commonly used by commercial growers. Rather, selected cultivars are generally propagated by T-budding in late summer or by whip grafting in the greenhouse in winter onto seedling rootstock. [17] [10] : 102
Micropropagation of flowering dogwood is now used in breeding programs aiming to incorporate resistance to dogwood anthracnose and powdery mildew into horticulturally and economically important cultivars. Nodal (axillary bud) sections are established in a culture of Woody Plant Medium (WPM) amended with 4.4 μmol/L 6-Benzyladenine (BA) to promote shoot growth. [19] Rooting of up to 83% can be obtained when 5–7 week-old microshoots are then transferred to WPM amended with 4.9 μmol/L IBA. [20]
Dogwood anthracnose caused by the fungi Discula destructiva has caused severe mortality of dogwoods. [21] In regions where dogwood anthracnose is a problem, homeowners and public land managers are encouraged to know the symptoms and inspect trees frequently. The selection of healthy, disease-free planting stock is essential and transplanting trees from the forest, particularly from mountain forests, should be avoided. [22] Species of Phytophthora cause root rot. [23]
Native Americans used the bark and roots in a remedy for malaria; a red dye was also extracted from the roots. [24] The species has been used in the production of inks, scarlet dyes, and as a quinine substitute. The hard, dense wood has been used for products such as golf club heads, mallets, wooden rake teeth, tool handles, jeweler's boxes and butcher's blocks. [25] [10] : 100 Cornus florida is the state tree and flower of Virginia, [26] the state tree of Missouri, and state flower of North Carolina. [27] [28] It was used to treat dogs with mange, which may be how it got its name. [28] The red berries are not edible, despite some rumors otherwise. [29]
In 1915, 40 dogwood saplings were donated by the U.S. to Japan in the 1912-15 exchange of flowers between Tokyo and Washington, D.C. While the cherry blossom trees survived the ensuing sour relations of these two countries and are the main feature of the National Cherry Blossom Festival, all dogwood trees in Tokyo died except the one that had been planted in an agriculture high school. In 2012, the United States sent 3,000 dogwood saplings to Japan to commemorate the 100th anniversary of the Washington, D.C., cherry trees given as a gift to the U.S. by Japan in 1912. [30] [31]
Quercus velutina, the black oak, is a species of oak in the red oak group, native and widespread in eastern and central North America. It is sometimes called the eastern black oak.
Cornus is a genus of about 30–60 species of woody plants in the family Cornaceae, commonly known as dogwoods, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduous trees or shrubs, but a few species are nearly herbaceous perennial subshrubs, and some species are evergreen. Several species have small heads of inconspicuous flowers surrounded by an involucre of large, typically white petal-like bracts, while others have more open clusters of petal-bearing flowers. The various species of dogwood are native throughout much of temperate and boreal Eurasia and North America, with China, Japan, and the southeastern United States being particularly rich in native species.
Platanus × acerifolia, Platanus × hispanica, or hybrid plane, is a tree in the genus Platanus. It is often known by the synonym London plane or London planetree. It is a hybrid of Platanus orientalis and Platanus occidentalis.
Lagerstroemia, commonly known as crape myrtle, is a genus of around 50 species of deciduous and evergreen trees and shrubs native to the Indian subcontinent, southeast Asia, northern Australia, and other parts of Oceania, cultivated in warmer climates around the world. It is a member of the family Lythraceae, which is also known as the loosestrife family. The genus is named after Swedish merchant Magnus von Lagerström, a director of the Swedish East India Company, who supplied Carl Linnaeus with plants he collected. These flowering trees are beautifully colored and are often planted both privately and commercially as ornamentals.
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture. Typically, they also look different from the parts of the flower, such as the petals or sepals. A plant having bracts is referred to as bracteate or bracteolate, while one that lacks them is referred to as ebracteate and ebracteolate, without bracts.
Salvia spathacea, the California hummingbird sage or pitcher sage, is a species of flowering plant in the family Lamiaceae, native to southern and central California growing from sea level to 610 m (2,001 ft). This fruity scented sage blooms in March to May with typically dark rose-lilac colored flowers. It is cultivated in gardens for its attractive flowering spikes and pleasant scent.
Cornus kousa is a small deciduous tree 8–12 m (26–39 ft) tall, in the flowering plant family Cornaceae. Common names include kousa, kousa dogwood, Chinese dogwood, Korean dogwood, and Japanese dogwood. Synonyms are Benthamia kousa and Cynoxylon kousa. It is a plant native to East Asia including Korea, China and Japan. Widely cultivated as an ornamental, it is naturalized in New York State.
Cornus nuttallii, the Pacific dogwood,western dogwood, or mountain dogwood, is a species of dogwood tree native to western North America. The tree's name used by Hul'q'umi'num'-speaking nations is Kwi’txulhp.
Cornus canadensis is a species of flowering plant in the dogwood family Cornaceae, native to eastern Asia and North America. Common names include Canadian dwarf cornel, Canadian bunchberry, quatre-temps, crackerberry, and creeping dogwood. Unlike its relatives, which are for the most part substantial trees and shrubs, C. canadensis is a creeping, rhizomatous perennial growing to about 20 centimetres tall.
Quercus coccinea, the scarlet oak, is a deciduous tree in the red oak section Lobatae of the genus Quercus, in the family Fagaceae.
Cornus sericea, the red osier or red-osier dogwood, is a species of flowering plant in the family Cornaceae, native to much of North America. It has sometimes been considered a synonym of the Asian species Cornus alba. Other names include red brush, red willow, redstem dogwood, redtwig dogwood, red-rood, American dogwood, creek dogwood, and western dogwood.
Xerochrysum bracteatum, commonly known as the golden everlasting or strawflower, is a flowering plant in the family Asteraceae native to Australia. Described by Étienne Pierre Ventenat in 1803, it was known as Helichrysum bracteatum for many years before being transferred to a new genus Xerochrysum in 1990. It is an annual up to 1 m (3.3 ft) tall with green or grey leafy foliage. Golden yellow or white flower heads are produced from spring to autumn; their distinctive feature is the papery bracts that resemble petals. The species is widespread, growing in a variety of habitats across the country, from rainforest margins to deserts and subalpine areas. The golden everlasting serves as food for various larvae of lepidopterans, and adult butterflies, hoverflies, native bees, small beetles, and grasshoppers visit the flower heads.
Cornus alternifolia is a species of flowering plant in the dogwood family Cornaceae, native to eastern North America, from Newfoundland west to southern Manitoba and Minnesota, and south to northern Florida and Mississippi. It is rare in the southern United States. It is commonly known as green osier, alternate-leaved dogwood, and pagoda dogwood.
Cornus alba, the red-barked, white or Siberian dogwood, is a species of flowering plant in the family Cornaceae, native to Siberia, northern China and Korea. It is a large deciduous surculose (suckering) shrub that can be grown as a small tree. As a popular ornamental used in landscaping its notable features include the red stems in fall (autumn) through late winter, bright winter bark; and the variegated foliage in some cultivars, such as C. alba 'Elegantissima'. C. alba can grow to 3 m (10 ft) high, but variegated forms are less vigorous. For the brightest winter bark, young shoots are encouraged by cutting to the ground some older stems at the end of the winter, before leaves are open. The oval fruits are white, sometimes tinted blue.
Fittonia is a genus of evergreen perennial flowering plants in the acanthus family, Acanthaceae. The genus is native to tropical and subtropical forested areas in northern and western South America, mainly Perú.
Oidium mangiferae is a plant pathogen that infects mango trees causing powdery mildew. Powdery mildew of mango is an Ascomycete pathogen of the Erysiphales family that was initially described by Berthet in 1914, using samples collected from Brazil. O. mangiferae is found in all areas where mangoes have been raised long term, but is particularly widespread in India where both the host and the pathogen are native. Currently no teleomorph stage has been identified, but due to certain morphological characteristics it has been suggested that O. mangiferae belongs in the Erysiphe polygony group. Mango is the only known host for this pathogen, though O. mangiferae appears to be identical to fungi responsible for powdery mildew diseases on various other plant species, particularly oak, though some differences may be observed. In particular, the number of cells in conidiophores varies from 2 on mango to 3-5 on oak. O. mangiferae has been known to infect oak leaves in the laboratory, however due to the lack of a known teleomorph stage O. mangiferae is still considered to only be a pathogen of mango. Recent analysis of its ribosomal DNA suggests it is conspecific with Erysiphe alphitoides, the causative agent of powdery mildew in European oaks.
Carya tomentosa, commonly known as mockernut hickory, mockernut, white hickory, whiteheart hickory, hognut, bullnut, is a species of tree in the walnut family Juglandaceae. The most abundant of the hickories, and common in the eastern half of the United States, it is long lived, sometimes reaching the age of 500 years. A straight-growing hickory, a high percentage of its wood is used for products where strength, hardness, and flexibility are needed. The wood makes excellent fuel wood, as well. The leaves turn yellow in Autumn.
Liatris spicata, the dense blazing star, prairie feather, gayfeather or button snakewort, is a herbaceous perennial flowering plant in the family Asteraceae. It is native to eastern North America where it grows in moist prairies and sedge meadows.
Euonymus americanus is a species of flowering plant in the family Celastraceae. Common names include strawberry bush, American strawberry bush, bursting-heart, hearts-a-bustin, and hearts-bustin'-with-love. It is native to the eastern United States, its distribution extending as far west as Texas. It has also been recorded in Ontario.
Parkia filicoidea, or African locust bean, is a large, spreading flat-crowned tree to 30 metres tall, the bole of which may be narrowly buttressed to a height of about 3 metres, and up to 120 cm DBH. It occurs in wet evergreen or semi-deciduous forest, sometimes on forest fringes, riverbanks and lakes, termite mounds, at elevations up to 1000 metres from Côte d’Ivoire, east to Sudan and Somalia, Uganda, Kenya, Malawi and south to Angola, Zambia, Zimbabwe and Mozambique. Bark on trunk scaly or smooth, grey to yellow-brown, branchlets glabrous to puberulous.