Grand fir (Abies amabilis)

Description

Abies grandis (grand fir,giant fir,lowland white fir,great silver fir,western white fir,Vancouver fir,or Oregon fir) is a fir native to the Pacific Northwest and Northern California of North America,occurring at altitudes of sea level to 1,800 m.It is a major constituent of the Grand Fir/Douglas Fir Ecoregion of the Cascade Range.The tree typically grows to 40?70 m in height.There are two varieties,the taller coast grand fir,found west of the Cascade Mountains,and the shorter interior grand fir,found east of the Cascades.It was first described in 1831 by David Douglas.It is closely related to white fir.The bark has historical medicinal properties,and it is popular in the United States as a Christmas tree.Its lumber is a softwood,and it is harvested as a hem fir.It is used in paper-making,as well as construction for framing and flooring,where it is desired for its resistance to splitting and splintering.The grand fir was first described by Scottish botanical explorer David Douglas,who in 1831 collected specimens of the tree along the Columbia River in the Pacific Northwest.Abies grandis is a large evergreen coniferous tree growing to 40?70 m (exceptionally 100 m) tall and with a trunk diameter of up to 2 m.The leaves are needle-like,flattened,3?6 cm long and 2 mm wide by 0.5 mm thick,glossy dark green above,and with two green-white bands of stomata below,and slightly notched at the tip.The leaf arrangement is spiral on the shoot,but with each leaf variably twisted at the base so they all lie in two more-or-less flat ranks on either side of the shoot.On the lower leaf surface,two green-white bands of stomata are prominent.The base of each leaf is twisted a variable amount so that the leaves are nearly coplanar.Different length leaves,but all lined up in a flat plane,is a useful way to quickly distinguish this species.The cones are 6?12 cm long and 3.5?4.5 cm broad,with about 100-150 scales;the scale bracts are short,and hidden in the closed cone.The winged seeds are released when the cones disintegrate at maturity about 6 months after pollination.