Pseudotsuga menzeisii, the Douglas-fir, “Nature’s All-Purpose Tree”
It’s a spruce, it’s a pine, it’s a…. well…what is it? Since it was first noted by Archibald Menzies in 1793, taxonomists have called it a pine, a spruce, a hemlock, and a fir. In fact, before Pseudotsuga menzeisii, the botanical name for Doug-fir was Pseudotsuga taxifolia, meaning, a false hemlock with yew-like foliage. Despite the apparent difficulty classifying the tree, it is easy to identify by its distinct cone. In Native American lore, a Douglas-fir invited a mouse to escape a sweeping forest fire by hiding in its cones. We can still see the hind feet and tail peaking out from beneath the scales! These three pronged bracts are unique to the genus and are seen in varying forms on other species.
Barring what the tree is not, what the Douglas-fir is, is remarkable. It is the most common tree in thePacific Northwest, accounting for 8 out of every 10 trees! The ultimate generalist, Doug-firs are variously early successional, late successional, and monotypic, depending on the climate and fire regime. This ability is owed to some shade tolerance and thick bark, which protects the tree from fire.
Earlier this month, I wrote about a giant left over from a previous epoch and a tree we widely recognize as the tallest in the world: the coastal redwood. What is less widely known is that the Douglas-fir is the second tallest tree in the world, and may once have competed with the redwood as the tallest –over 400 feet. Though no Tree of Life <link to Western Red Cedar> , the Douglas-fir was nonetheless important for medicine, wood, and deodorizing. Today, the Douglas-fir “furnishes more products for use than any other tree in the world” according to Edward Jensen. For the fungi-philes out there, the Douglas-fir furnishes something else: a delicious mycorrhizal associate – the chanterelle.
Five Doug-firs grace the Heritage Tree list including #134 on the TREEsure map atLowerMacleayPark. This is the tallest tree inPortland, at 242 feet. For East Portlanders, Heritage Tree #279 is located on the walking trail at Glendoveer Golf Course along the north fenceline.