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Fraser fir
was named for John Fraser (1750-1811), a Scot botanist who explored
the southern Appalachian Mountains in the late 18th century. The species
is sometimes called Southern balsam or Southern balsam fir. Locally
Fraser fir is known as "She balsam" because of the resin filled blisters
on the tree's trunk. Red spruce, often associated with Fraser fir, is
called "He balsam" and lacks the distinctive blisters. 
Fraser fir is a
uniformly pyramid-shaped tree which reaches a maximum height of about
80 feet and a diameter of 1-1.5 feet. Strong branches are turned slightly
upward which gives the tree a compact appearance. Leaves (needles) are
flattened, dark-green with a medial groove on the upper side and
two broad silvery-white bands on the lower surface. These bands consist
of several rows of stomata (pores). Leaves are 1/2 to one inch long,
have a broad circular base, and are usually dark green on the upper
surface and lighter on the lower surface. On lower branches, leaves
are two-ranked (occurring in two opposite rows). On upper twigs, leaves
tend to curl upward forming a more "U-shaped" appearance.
Fraser
fir is monecious meaning that both male and female flowers (strobili)
occur on the same tree. Flowers are receptive in May to June depending
on elevation and other environmental conditions. The species is wind
pollinated, and cones mature in a single season. At maturity, cones
are 2-2 1/2 inches long with bracts longer than the scales and appearing
reflexed (bent over). The presence of these visible cone bracts is a
distinguishing feature of Fraser fir as compared to balsam fir. Upon
ripening in September to November, cones fall apart leaving an erect
central core. Red squirrels are the primary consumers of seeds.
Bark is usually
gray or gray-brown, thin, smooth with numerous resin blisters on young
trees. As trees become older, the bark tends to develop into thin, papery
scales.
Fraser fir is intermediate in shade tolerance and is usually found on
fertile, rocky to sandy soils which are acidic. Natural associates are
red spruce, beech and yellow birch. Rhododendrons also are found in
this ecosystem, and add significant beauty during their flowering season.
The
most damaging natural enemy is the balsam woolly adelgid (formerly called
an aphid) which is an imported, wingless insect. Phytophthora root disease
attacks Fraser fir, but is most harmful at lower elevations. Some scientists
also point to air pollution as a contributor to the decline of many
natural red spruce-Fraser fir stands. The combination of form, needle
retention, dark blue-green color, pleasant scent and excellent shipping
characteristics has led to Fraser fir being a most popular Christmas
tree species. North Carolina produces the majority of Fraser fir Christmas
trees. It requires from 7 to 10 years in the field to produce a 6-7
feet tree.
Fraser fir
has a somewhat restricted range. It grows naturally only at elevations
above 4,500 feet in the Southern Appalachian Mountains from southwest
Virginia, through western North Carolina, and into eastern Tennessee.
A number of stands occur in the Great Smoky Mountains National Park.
Its highest native habitat is Mt. Mitchell, North Carolina (6,684 feet)
which is the highest U.S. point east of the Mississippi River. A variety
of balsam fir, phanerolepis, occurs in the Northeast United States and
Canada and as far south as West Virginia and Virginia (38 degees north
latitude). This variety is best described as an intermediate form between
balsam fir and Fraser fir and may represent a remnant of a once continuous
range of the two species.
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