Douglas-fir

Leaves

Form

• Needles evergreen
• Remaining on tree for 5–8 years
• Flat, flexible, grooved above
• Often sharp-pointed
• Narrowed at the base into a slender short stalk, set on a leaf-cushion
• Needles spirally arranged along the twig
• On horizontal branches, spreading out from the sides in 2 ranks or spreading out from 3 sides and moderately parted on the upper side
• Midvein prominent
• 2 resin ducts visible in cross-section
• Slight apple odour when crushed

Length

• 2–3 cm

Colour

• Upper surface bright yellowish-green
• Lines of white dots on lower surface

Buds

Form

• Terminal bud narrowly conical, sharp-pointed
• A small cluster of lateral buds occurs just below the terminal bud, separated by a few needles
• Other lateral buds scattered along the twig

Length

• Up to 10 mm

Colour

• Many shiny reddish-brown overlapping scales

Twigs

Form

• Moderately stout and flexible, hairy
• Leaf-cushion a low ridge of bark darkened at the forward end
• After the needles have fallen, the branchlets show slightly raised oval scars on the leaf-cushions

Colour

• Greenish-brown becoming greyish-brown

Seed cones (immature)

Form

• Conelets borne in the upper part of the crown, in leaf axils near the forward end of previous year’s twig
• Seed-cone buds are larger than shoot buds

Length

• About 30 mm

Colour

• At pollination, green to purple to red

Structure

• Oblong at pollination
• Erect, short-stalked, with distinctive 3-pronged bracts extending beyond the scales and partially obscuring them
• After pollination, the cone stalk bends downward

Timing

• Mature in late summer of first season

Pollen cones

Form

• Cylindrical to conical, fleshy, catkin-like, pendulous
• Pollen-cone buds are paler than shoot buds

Length

• 10–20 mm

Colour

• Yellow to orange-red

Structure

• Borne in the upper-middle, middle, and lower parts of the crown, in leaf axils of previous year’s twigs

Timing

• Pollination takes place in early spring as new leafy shoots start to elongate; cones then wither and fall away

Seed cones (mature)

Form

• Narrowly ovoid
• Pendulous on stout stalks

Length

• 6–9 cm

Colour

• Yellowish-brown to purplish-brown

Structure

• Scales numerous, broad, rounded, leathery
• Bracts prominent, 3-pronged, longer than the scales

Timing

• Seeds shed throughout fall, winter, and spring
• Cones drop intact after seed dispersal

Seeds

Form

• Somewhat triangular

Length

• Seed 5–7 mm
• Seed wing 15–18 mm

Colour

• Seed shiny reddish brown

Seedlings

Form

• Newly germinated seedlings with a stalk surmounted by a whorl of 5–10 upcurved cotyledons with smooth edges
  
• Needles form above the cotyledons, clustered at first, later spreading along the new shoot

Length

• Seedlings about 4 cm
• Cotyledons about 2 cm

Colour

• Cotyledons green
  

Bark

Form

• Smooth, thin, resin-blistered when young
• Becoming deeply furrowed with irregular, broad ridges
• Up to 30 cm thick

Colour

• Grey when young, becoming dark reddish-brown

Wood

Texture

• Moderately heavy and hard
• Exceptionally strong

Colour

• Heartwood reddish-brown
• Sapwood yellowish-white

Morphology

• Marked contrast between earlywood and latewood
• Resin ducts present

Uses

• Wood pulp, lumber
• Used for structural purposes
• Shipbuilding, laminated beams, interior and exterior finishings
• Boxes, railway ties, piling and decking for marine structures

Size

Height

• To 60 m

Diameter

• To 200 cm

Maximum age

• 500 years

Tree form

Forest-grown

Trunk

• In old trees, long, branch-free, cylindrical

Crown

• In old trees, short, columnar, flat-topped
• In young trees, narrowly conical crowns often extend to the ground
• Principal branches in irregular whorls at the annual nodes, lesser branches in between
• Dead branches may remain on the trunk for years

Root system

• Strong, wide-spreading

Habitat

Site

• Varied soils, best growth on deep, well-drained, sandy loams and where moisture in the soil and atmosphere is plentiful
• Commonly a pioneer species that regenerates after forest fires, logging, and other disturbances

Light tolerance

• Requires some shade in first year but then thrives in sunlight
• Less shade-tolerant than its associates

Associated species

• Western hemlock, amabilis fir, western redcedar, and grand fir

Range

Vancouver Island and the Pacific coast from central British Columbia to California