Fraser Fir

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Fraser Fir
Foliage and cone
Conservation status
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Pinaceae
Genus: Abies
Species: A. fraseri
Binomial name
Abies fraseri
(Pursh) Poir., 1817
Natural range of Abies fraseri

Fraser Fir (Abies fraseri) is a species of fir native to the mountains of the eastern United States. It is closely related to Balsam Fir (Abies balsamea), of which it has occasionally been treated as a subspecies (as A. balsamea subsp. fraseri (Pursh) E.Murray) or a variety (as A. balsamea var. fraseri (Pursh) Spach).[2][3][4][5]

Names

Fraser Fir on the Slopes of Clingman's Dome

The species is named after the Scottish botanist John Fraser (1750–1811), who made numerous botanical collections in the region.[3] It is sometimes misspelled as "Frazer" or "Frazier".

In the past, it was also sometimes known as "she-balsam" because resin could be "milked" from its bark blisters,[6] in contrast to the "he balsam" (Red Spruce) which could not be milked. It has also occasionally been called balsam fir, inviting confusion with A. balsamea.[7]

Description

Seedlings of Fraser fir (blue-green, longer needles) and Red Spruce (green, shorter needles)

The Fraser Fir is a small evergreen coniferous tree growing to between 30 and 50 feet (10–15 m) tall (rarely to 80 ft [25 m]) with a trunk 16 to 20 inches (40–50 cm) across (rarely up to 30 in, 75 cm). The crown is conical, with straight branches either horizontal or angled 40° upward from the trunk; it is dense when the tree is young, but becomes more open as it ages. The bark is thin and smooth, gray-brown with numerous resin blisters on young trees, becoming fissured and scaly with age. The foliage is strongly turpentine-scented.

The leaves are needle-like, arranged spirally on the twigs but twisted at the base to spread in two rows; they are 0.4 to 0.9 inches (10–23 mm) long and 79 to 87 mils of an inch (2–2.2 mm) broad, flat and flexible with a rounded or slightly notched tip, dark green to glaucous green above, often with a small patch of stomata near the tip, and with two silvery white stomatal bands on the underside.

The cones are erect, cylindric, 1.4 to 2.75 inches (3.5–7 cm) long (rarely to 3.2 in [8 cm]) and 1.0 to 1.2 inches (2.5–3 cm) broad (rarely as broad as 1.5 in [4 cm]) broad, dark purple, turning light brown when mature, with long reflexed green, yellow or pale purple bract scales, and often resinous. The cones disintegrate when mature at four to six months old to release the winged seeds.[2][3][4]

The balsam fir variety Abies balsamea var. phanerolepis is regarded by some botanists as a natural hybrid between balsam fir and Fraser fir, as Abies × phanerolepis (Fernald) Liu.[3]

Ecology

Distribution

Fraser Fir forest, with many trees killed by Balsam woolly adelgid

The Fraser Fir is restricted to the southeastern Appalachian Mountains in southwestern Virginia, western North Carolina and eastern Tennessee, where it occurs at high elevations, from 3,900 feet to the summit of Mount Mitchell, the highest point in the region at 6,683 feet (1,200 m up to 2,037 m). It lives in acidic moist but well-drained sandy loam, and is usually mixed with Picea rubens (Red Spruce). Other trees it grows with include Tsuga caroliniana (Carolina Hemlock), Betula alleghaniensis (Yellow Birch), Betula papyrifera (Paper Birch), and Acer saccharum (Sugar Maple). The climate is cool and moist, with short, cool summers and cold winters with heavy snowfall.[2][3]

Pests

The species is severely damaged by a non-native insect, the Balsam woolly adelgid (Adelges piceae). The insect's introduction and spread led to a rapid decline in Fraser fir across its range, with over 80 percent of mature trees having been killed. The rapid regeneration of seedlings with lack of canopy has led to good regrowth of healthy young trees where the mature forests once stood. However, when these young trees get old enough for the bark to develop fissures, they may be attacked and killed by the adelgids as well. For this reason, the future of the species is still uncertain, though the Mount Rogers (Virginia) population has largely evaded adelgid mortality. The decline of the Fraser fir in the southern Appalachians has contributed to loss of moss habitat which supports the Spruce-fir moss spider.[5]

Cultivation and uses

Although not important as a source of timber, Fraser Fir is widely used as a Christmas tree. Its mild fragrance, shape, strong limbs, and ability to retain its soft needles (which do not prick easily when hanging ornaments) for a long time when cut make it one of the best trees for this purpose.[8] Fraser Fir has been used more times as the Blue Room Christmas tree (the official Christmas tree of the President of the United States's White House) than any other type of tree.[citation needed]

It is grown in plantations in Scotland and sold by the thousands throughout the United Kingdom and Ireland.[citation needed] It is also cultivated from seedlings in several northern states in the USA and adjacent parts of Quebec province especially for the Christmas tree trade.[citation needed]

See also

References

  1. ↑ Farjon, A. (2011). "Abies fraseri". IUCN Red List of Threatened Species. Version 3.1. International Union for Conservation of Nature. Retrieved 2013-11-10. 
  2. ↑ 2.0 2.1 2.2 Farjon, A. (1990). Pinaceae. Drawings and Descriptions of the Genera. Koeltz Scientific Books ISBN 3-87429-298-3.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 Liu, T.-S. (1971). A Monograph of the Genus Abies. National Taiwan University.
  4. ↑ 4.0 4.1 Flora of North America: Abies fraseri
  5. ↑ 5.0 5.1 Gymnosperm Database: Abies fraseri
  6. ↑ Frankenberg, D. (2000). Exploring North Carolina's Natural Areas: Parks, Nature Preserves, and Hiking Trails. Chapel Hill: University of North Carolina Press. ISBN 0-8078-4851-4.  p343
  7. ↑ Sutton, M., & Sutton, A. (1985). Eastern forests (Audubon Society Nature Guides). New York: Knopf. ISBN 0-394-73126-3.  p363
  8. ↑ Hendrix, Steve, "A Christmas tree’s remarkable journey", The Washington Post, December 21, 2011.

External links

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