Pseudotsuga menziesii var menziesii

The Coast Douglas fir is one of the tallest trees in the world. The Mineral tree, near Mineral, in Lewis County, was measured at 120 meters (393 feet) in 1924. There is a 1901 report of logging a douglas fir 411 feet tall. However, the tallest living Douglas fir today is only 326 feet, easily eclipsed by the largest Coast redwood (Sequoia sempervirens) at 379 feet tall. The tallest tree ever measured was an Australian mountain ash (Eucalyptus regnans), 435 feet tall. That tree was also promptly logged.

Douglas fir is still economically important here in Wastern Washington. In 2010, 46,052 thousand board feet of Douglas fir were harvested in King County alone. Douglas fir wood has a very high strength-to-weight ratio, so is used extensively for structural timbers and plywood. Douglas fir also accounts for more than half the Christmas trees produced in Washington State.

Douglas fir is an early seral species. After a disturbance such as fire or logging, the forest can regrow into an almost pure Douglas fir stand, though most timberlands are now planted with seedlings to give them a jump on the red alders (Alnus rubra) which can otherwise shade them out. Since a Douglas fir can live over 750 years, they remain an important species in older forests as well.

Douglas firs begin to produce strobili (cones) at about 12-15 years of age. It takes about 17 months from the start of bud development to cone maturation. The seeds are wind dispersed, and usually fall within 150 meters of the parent tree, though they can travel for over a kilometer. Seed production varies by year, with a heavy crop every seven years or so. Trees 200-300 years old produce the most seeds.


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