Fraxinus americana

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Fraxinus americana
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Lamiales Family: Oleaceae Genus: Fraxinus Species: F. americana
Binomial name
Fraxinus americana L.

Fraxinus americana (White Ash or American Ash) is a species of Fraxinus native to eastern North America found in mesophytic hardwood forests from Nova Scotia west to Minnesota, south to northern Florida, and southwest to eastern Texas.^[1]

It is a large deciduous tree growing to 20–30 m tall, exceptionally to 50 m, with a trunk 0.5–1.8 m diameter. The bark is smooth and gray on young trees, becoming fissured with age. The winter buds are dark brown or reddish-brown, with a velvety texture. The leaves are 20-30 cm long, pinnately compound with seven (occasionally five, nine or eleven) leaflets, these 5–15 cm (rarely 18 cm) long and 3–7.5 cm broad, with serrated margins and short but distinct petiolules up to 15 mm long. They are green above, whitish glaucous below, and turn yellow, red, or purple in the fall. The flowers are small, purplish, without petals; like all ashes, is usually dioecious, with male and female flowers being borne on separate trees. Flowering occurs in early spring after 30-55 growing degree days, before the new leaves expand; pollination is by wind. The fruit is a samara 2.5-6.5 cm long and 4–7 mm broad when fully formed, the seed 1.5-2 cm long with a pale brown wing 1.5-4 cm long, and can be blown a good distance from the parent tree.^{[2][3][4][5][6]}

The natural lifespan is up to a maximum of about 300 years.^[7]

The name White Ash derives from the glaucous undersides of the leaves. It is similar in appearance to the Green Ash, making identification difficult. The lower sides of the leaves of White Ash are lighter in color than their upper sides, and the outer surface of the twigs of White Ash may be flaky or peeling. Green Ash leaves are similar in color on upper and lower sides, and twigs are smoother. Also, these species tend to occupy different habitat niches, with White Ash found in moist upland sites and Green Ash in wet forests of floodplains or swamps, although there is some overlap in habitat distribution.^[2][4]

White Ash is also a food plant for the larvae of several Lepidoptera species - see List of Lepidoptera that feed on ashes.

[edit] Cultivation and uses

The wood is white, strong, and straight-grained. It is the timber of choice for production of baseball bats and tool handles. The wood is also favorable for furniture and flooring.

It is widely grown as an ornamental tree in North America. Cultivars selected for superior fall color include 'Autumn Applause' and 'Autumn Purple'.

Other names occasionally used for the species include Biltmore ash, Biltmore white ash and cane ash.

[edit] References