Douglas Fir is a “false fir”, as its botanical name, Pseudotsuga menzesii implies : pseudo = false, and Tsuga is the genus name for hemlock, which resembles firs. Despite its name, this tree is a handsome, large evergreen, named after David Douglas (1799- 1834), a Scotsman reputed to be the greatest of all botanical explorers.
Douglas Fir is native to the western United States and Canada but now grows all over the country, including Ewing, NJ. It is among the tallest conifers in the world, second only to Coast Redwoods, and has been known to reach 330’ in its native habitat; 40’ to 80’ tall and 12’-20’ in spread is more common, however, and its USDA Hardiness Zone is 4-6 (Ewing is USDA Zone 6b). It is reported to live more than 500 years in good habitats, and one tree is reported to have survived 1000 years.
The leaves ( needles), are flat and spirally arranged on the stems. The bark is thin, smooth and grey in youth, turning reddish-brown and ridged, with resin “blisters” in maturity; the needles are deep green; it has a resinous, fruity odor. The pendant cones are oval, usually reaching 2-3” long and have long bracts projecting from the scales. The cones persist into winter. The shape of the tree is open-pyramidal with straight, stiff branches. The lower branches in older specimens droop but are retained for a long time.
Douglas Fir does poorly in windy or crowded areas. It needs deep, cool, well-drained, neutral to slightly acid soil, and full sun. It seems to be fairly fire and drought-tolerant. It transplants well balled and burlapped. Be warned, however, that Pseudotsuga menzesii hosts many insect pests and needs monitoring in residential and park landscapes.
This is a very ornamental tree which is outstanding in the landscape as a specimen or in a group. The seeds are important food for mice, voles, chipmunks and squirrels, and the tree is a favorite habitat for many species of birds. The needles are a favorite food for porcupines and blue grouse. The buds are used to flavor eau de vie and colorless fruit brandy, and it is very popular as a Christmas tree, especially since the needles do not fall easily.
This tree, with its very strong but lightweight wood, yields more timber than any other North American tree: it is used for dimensional lumber, timbers, plywood, railroad ties, furniture, posts, fencing and flooring.
Ann Farnham, LLA
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