Common name: Douglas-fir

Scientific Name: Psuedotsuga menziesii
“Psuedo”= false; “tsuga”= hemlock
“menziesii”= name of first person to identify the tree

Description:  This tree grows to 70m (210 feet) tall on average, occasionally reaching heights of 80-90m (240-270 feet).  The crown of the Douglas-fir is pointy, like a pyramid, while the lower half of the tree skirts out in an irregular pattern. The branches are spreading with a slight droop. The bark is thick, rough, grayish-brown, with deep crevasses in between ridges. The bark can be up to 12 inches thick. The needles spiral around the central branch in a bottle brush structure.  Each individual needle is flat, bright green, with two lobes on the tip (not pointy).  A single groove that runs the length of the needle can be seen on the upper side of each needle and two white grooves on the underneath side (Pojar and Makinnon 1994). When the needles are removed, a flat, circular scar is left behind.  Cones point downward and have three forked bracts that resemble the feet and tail of a mouse protruding from beneath each seed shield.

Geographical range: The geographical range of this tree extends along the coastline and slightly interior from British Columbia, Canada, to the coastline of Northern California, U.S. Patches of the Douglas-fir also exist through the western region of the U.S.

Habitat:  This tree inhabits a multitude of climates from dry lowland forests, to moist upland forests.  However, it does primarily establish in an environment with direct sunlight and moist soils.

Reproduction:  Both male and female cones are present on one tree. Pollen from the male cone is wind dispersed and pollinates the female cone.  When the female cone is fertilized, the cone develops seeds and matures on the tree.  The seeds are spread when either a small animal rips the cone open to eat the seeds and accidentally drops or stashes a viable seed or when the cone opens naturally and drops the seeds upon the forest floor.

Input requirements (food supply): Like all plants, the Douglas fir tree depends on photosynthesis for its survival. Using the energy of the sun, the tree chemically converts nutrients, water, and air into sugars and carbohydrates on which it feeds.  This process is called photosynthesis.

Role in the ecosystem: This tree creates a habitat for insects, small mammals (including Northern flying squirrels and red tree voles), and many epiphytic plants (like lichens and mosses).  This tree is also important for supporting thousands of species of microscopic fungi and Scuzz.  Scuzz in an compound comprised of fungus, yeast, and bacteri. Scuzz lives on top of and inside the needles of the fir and supports an intricate food web of insects and mammals.

Use as a Human Resource: Douglas-fir has been historically used by humans as a vital resource.  The wood was used by Native American tribes to make spears, spoons harpoon shafts, salmon weirs, fire tongs, caskets, and fishhooks. The pitch (sap) was used as a medicinal salve for wounds and skin irritations.  The Nuxalk, Quinalt, and other tribes made torches using the pitch of the Douglas-fir (Pojar and Makinnon 1994).
Douglas-fir is probably the most sought after tree for present day timber harvesting. According to Franklin et al (1981), Douglas fir is a relatively fast growing tree, maturing in 60-70 years.  It is also highly demanded as timber because it grows straight up due to the direct exposure and has straight fibers, thus making it easier to process and a more dependable timber product.

Notes: The Douglas-fir can live to be 1000 years old.  Its thick bark protects the tree from fire and many old-growth forest Douglas-firs show a legacy of fires through their burn scars.  This tree arrived in our region approximately 7,000 years ago, shortly after the retreating of the ice sheets that ended with the Pleistocene era (the Ice Age) (Pojar and Makinnon 1994).

Resources:
Pojar, J. and A. MacKinnon. 1994. Plants of the Pacific Northwest Coast; Washington, Oregon, British Columbia, and Alaska. Lone Pine Publishing, Redmond, WA. 528 pp.