Fir, Douglas (Pseudotsuga menziesii)
Douglas fir is an evergreen conifer native to North America.
Common name: Douglas fir
Scientific name: Pseudotsuga menziesii
UK provenance: non-native
Interesting fact: Douglas fir bark is non-flammable. This protects the tree from fires in its native range.
What does Douglas fir look like?
Overview: can grow to 55m and live for more than 1000 years. It was introduced to the UK in 1827 by Scottish botanist David Douglas. The bark of young trees is grey-green with highly scented blisters, and becomes purple-brown, thick and corky with horizontal fissures over time.
Leaves: needle-like leaves are flat, soft and flexible, and distributed around the twig. They are green in colour with white-green stripes on the underside. Buds resemble those of beech trees - they are red-brown, scaly and slender, and taper to a point.
Flowers: Douglas fir is monoecious, meaning both male and female flowers are found on the same tree. Male flowers are oval clusters of yellow stamens growing on the underside of the previous year's shoots. Female flowers are green to red upright tufts, and grow at the tips of twigs.
Fruits: after pollination by wind, female flowers develop into oval cones, which hang straight down from the branches and change in colour from yellow to pink to light brown. From each scale protrudes a unique three-pointed bract.
Look out for: the trunk has resin filled blisters and the scales on cones have three pointed tips. When crushed, the leaves have a sweet resin smell.
Could be confused with: other planted fir trees.
Identified in winter by: it is an evergreen so its features are present year round.
Where to find Douglas fir
Douglas fir can be found in a variety of habitats including open forests with plenty of moss and rainy conditions. It thrives in western areas of the UK, where rainfall is higher.
Value to wildlife
Because the trees are so long-lived, they provide deadwood cavities, in which birds and bats can shelter. Being tall, they also make suitable nesting sites for larger birds of prey, such as buzzards, sparrowhawks and hobbies.
The spruce carpet and dwarf pug moths feed on the leaves, while the seeds are eaten by finches and small mammals. In Scotland, Douglas fir forests provide habitats for the red squirrel and pine marten.
Mythology and symbolism
A Native American myth describes the unusual pointed cone bracts as the tail and hind legs of mice. It was said the mice hid in the cones to escape forest fires.
How we use Douglas fir
Douglas fir timber is of great commercial importance, and is used to make beams, veneers, furniture, cladding, decking and flooring.
Douglas fir can be vulnerable to infection by various fungal diseases.