White Ash

Appearance

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. White ash leaves turn yellow or red in autumn. Despite some overlap, the two species tend to grow in different locations as well; white ash is a forest tree that commonly occurs alongside sugar maple while green ash is a pioneer species that inhabits riparian zones and disturbed areas. The white ash's compound leaves usually have 7 leaflets per leaf whereas the counts in other ash trees more often vary.

Like other species in the section "Melioides", "Fraxinus americana" is dioecious, with male and female flowers produced on separate individuals.

Distribution

Isolated populations have also been found in western Texas, Wyoming, and Colorado, and the species is reportedly naturalized in Hawaii.

There are an estimated 8 billion ash trees in the United States – the majority being the white ash trees and the green ash trees.

Uses

White ash is one of the most used trees for everyday purposes and, to keep up with high demand, is cultivated almost everywhere possible. The wood is white and quite dense, strong, and straight-grained. Its species produces an ideal, atypical dominant excurrent structured crown. It is a traditional timber of choice for production of baseball bats and tool handles. The wood is also favorable for furniture and flooring. A study compared it to eight other different species, and it showed the highest antibacterial activity in the context of manufacturing chopping boards.

Woodworkers use the timber mainly for interior uses due to high perishability in contact with ground soil. It is also used to make lobster traps. Since the 1950s, it has also become a popular choice for solid electric guitar bodies. It makes a serviceable longbow if properly worked. The wood was used in ceiling fan blades from the 1970s through the mid-1980s, though cane was sometimes simulated with plastic then. It is no longer used for ceiling fan blades in most countries.

White ash is not seen in cultivation as often as green ash, due to its preference for undisturbed forest sites away from urban pollution and soil compaction. It sometimes has been planted for its consistently reliable autumn colors, which typically are bright orange and red hues as opposed to other species of ash that produce a uniform yellow color.

Cultivation of white ash differs across North American continent. For example, within the City of Chicago region, 2010 statistics show most common street tree species is white ash at 6.2%. Along with third ranked green type at 4.9%, ashes combine to make up 11% percent of the city's street trees, with an overall population of 13,648,044 million standing ashes within Cook County alone.

Autumn Purple, or Junginger, a wild variety of American white ash selected for its purple leaf color, was discovered by University of Wisconsin horticulturist Karl Junginger of McKay Nursery in Waterloo, Iowa. After its introduction in 1956, it quickly became the most popular and most expensive landscaping selection, surpassing the high priced ginkgo, London plane and white/burr oak. A related species, Biltmore ash, is sometimes treated as a variety of white ash. Other taxonomists argue that Biltmore ash is its own species.

North American native ash tree species are used by North American frogs as a critical food source, as leaves that fall from the trees are particularly suitable for tadpoles to feed upon in ponds, large puddles, and other water sources. Species such as red maple, which are taking the place of ash due to the ash borer, are much less suitable for the frogs as a food source — resulting in poor frog survival rates and small frog sizes. The lack of tannins in the American ash variety makes them a good food source for frogs, but are not resistant to the ash borer. Varieties of ash from outside North America typically have much higher tannin levels and resist the borer. Maples and various non-native invasive trees, trees that are taking the place of American ash species in the North American ecosystem, typically have much higher leaf tannin levels. Ash species native to North America also provide important habitat and food for various other creatures that are native to North America.