Douglas Fir
Pseudotsuga menziesii
The Douglas fir is an incredibly large coniferous tree, soaring 60-75 meters (200-250 ft) tall in old growth stands. The wide, straight trunks are branchless until the high foliage, as older trees lose their lower branches; the branches may start as high up as 34 meters or 100 feet from the ground. The bark of this tree varies greatly in appearance depending on age. Younger trees have smooth, thin, gray bark, while mature trees have thick, corky bark with deep vertical fissures. On older trees the layers of dark brown bark are intermixed with lighter, corky material and can be over a foot thick. The soft, flat needles, 2-4 cm long, completely encircle the branches. The scaly female cones, 6-10 cm long, droop down from the branches. The scales of the light brown cone have a distinctive edge, with three protruding points that resemble the back half of a mouse, with two feet and a long tail.
Basic Information
Member of the Pinaceae, or pine, family
Evergreen conifer
Commonly lives 500 years, though it can live over 1,000
The oldest specimen is over 1,300 years old
There are three varieties:
P. menziesii var. menziesii — coast Douglas-fir
This is the only douglas fir found on the SF Peninsula
P. menziesii var. glauca — Rocky Mountain Douglas-fir
P. menziesii var. lindleyana — Mexican Douglas-fir
Habitat
Native to coastal western North America, from west-centra British Columbia south to central California
In California, it is found in the Klamath and Coast Ranges as far south as the Santa Cruz Mountains, and in the Sierra Nevada as far south as the Yosemite region
Commonly found in mixed coniferous forests
Ecological Role
Douglas fir is a “keystone species” with great influence over the ecosystem
The trees capture enormous amounts of carbon
They also stabilize the soil, regulate temperature and hydrologic functions, and provide many more ecological functions
Numerous animals and plants rely on this tree as a food source and habitat
The seeds of this tree are an extremely important food source for small mammals, including moles, shrews, and chipmunks
These small mammals consume an estimated 65% of each annual seed crop
The Douglas squirrel hoards Douglas-fir cones and consumes many parts of the tree including the mature pollen cones, the inner bark, terminal shoots, and young needles
The inner bark is the primary winter food for the North American porcupine
Old growth Douglas-fir forest is the primary habitat of the red tree vole (Arborimus longicaudus) and the spotted owl (Strix occidentalis).
Breeding pairs of spotted owls need at least 400 ha (4 square kilometers, 990 acres) of old growth as home ranges
The red vole nests almost exclusively in the foliage of the trees and its diet consists chiefly of Douglas-fir needles
Large ungulates (hoofed mammals) generally don’t consume the needles, but in food-scarce winters it can become important
As an exception, black-tailed deer often browse new seedlings and saplings in spring and summer
The spring diet of the blue grouse prominently features Douglas-fir needles
Many insects also rely on this tree, including the woolly conifer aphid, the gelechiid moths Chionodes abella and C. periculella, and the tortrix moth
The bark of this tree is extremely thick, making it one of the most fire-resistant trees in the Pacific Northwest
Reproduction
Blooms from March-May
Alternative Names
Brummit Fir, Douglas spruce, Oregon pine, Columbian Pine, Douglas pine, Pudget Sound pine, red fir
The Coast Salish name in the Halkomelem language is lá:yelhp.
In the Lushootseed language, the tree is called čəbidac
Historical Uses
Being such an important and widespread tree, the Douglas fir played a massive role in Native American life, influencing medicine, diet, and culture
Widely used for medicinal purposes:
the bark, resin, and pine needles were used to make herbal treatments for various diseases
The Bella Coola mixed the resin with dogfish oil for many medicinal applications
Wood frequently used for firewood, tool making (bows, spears), and all forms of construction, including for floors, beams, and carvings
Native Hawaiians built the double hulled waʻa kaulua canoes from coast Douglas-fir logs that drifted ashore
Needles used as a coffee substitute
Additional Information
The Douglas fir is the second tallest conifer in the world, behind only the Coast Redwood
The tallest recorded tree was 393 feet tall
Prior to massive logging, Douglas firs often grew over 300 ft tall, though some ~1000-year-old titans like surpassed 400 ft in height
Douglas-fir may have been the tallest tree species on the planet; however, so many trees were lost to logging that it is impossible to know now
The tree trunk can reach a diameter 4.5-6 meters, or 15-20 feet
best timber-producing species in North America, yielding more timber than any other species on the continent
Many of the oldest stands of Douglas fir have been ravaged by logging, resulting in massive loss of habitat and ecosystem devastation
The few remaining patches of rapidly shrinking old growth are not large enough to support the animals and plants that previously relied on them