Cladus: Eukaryota Name Abies fraseri (Pursh) Poir. Reference Encycl. suppl. 5:35. 1817 Vernacular names Abies fraseri (Fraser fir) is a species of fir native to the mountains of the eastern United States and Canada. It is closely related to Abies balsamea (balsam fir), 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 The species is named after the Scottish botanist John Fraser (1750–1811), who made numerous botanical collections in the region.[3] It is sometimes mis-spelled 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 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
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 will likely be attacked and killed by the adelgids as well. For this reason, the future of the species is still uncertain. 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 Fraser fir is widely used as a Christmas tree. Its fragrance, shape, strong limbs, and ability to retain its soft needles for a long time when cut (which do not prick easily when hanging ornaments) make it one of the best trees for this purpose. The 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. It is grown in plantations in Scotland and sold by the thousands throughout the United Kingdom and Ireland. References 1. ^ Conifer Specialist Group (1998). Abies fraseri. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 11 May 2006. Listed as Vulnerable (VU D2 v2.3) .
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