Douglas Fir (Pseudotsuga menziesii)
The Arboretum's Conifer Collection hosts a variety of conifers native to the western US. A specimen of one of these, Douglas fir, can be found near the Pawpaw planting along Arboretum Drive below the Program Shelter. The scientific name Pseudotsuga, meaning false hemlock, reflects its resemblance to Hemlock (Tsuga), while the specific name menziessi recognizes Archibald Menzies who first discovered this tree on Vancouver Island in the 1790s. The common name pays tribute to David Douglas, an early British botanist/explorer who "rediscovered" the tree along the Columbia River Basin in the 1820s and later throughout the Pacific Northwest and the Rocky Mountain Region.
Two varieties of Douglas Fir are recognized - Coastal Douglas Fir (var. menziesii) occurs along the Pacific coast from central British Columbia south to northern California where it can grow to 300 ft. in height and 30 ft. in diameter. Rocky Mountain Douglas Fir (var. glauca) is found throughout the Rocky Mountain Region east of the Cascades and Sierra Nevada mountains south to Arizona and New Mexico. Our specimen planted in 1965 is var. glauca. The biggest trees (var. menziesii) in an ancient, old growth stand known as Cathedral Grove on Vancouver Island, British Columbia, are about 800 years, 250 ft. tall, and up to 29 ft. in diameter.
The dark green needles of Douglas Fir have white bands underneath and are spirally arranged, the branches resembling a bottle brush. The 3-inch cones are pendulous (as opposed to the upright cones of true firs, Abies spp.) and have distinctive 3-lobed seed bracts growing between the cone scales.
Douglas Fir is an important lumber tree with dense durable wood that is resistant to decay and used for many types of construction. It is also a popular Christmas tree. The seeds are an important food for squirrels, birds and other wildlife.
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