Red alder

Leaves

Form

• Oval to rhombic, tapered from the middle to both ends
• Thick, not sticky
• Veins hairy on lower surface
• 8–15 veins per side, impressed on upper surface
• Veinlets forming a ladder-like pattern
• Considerable leaf-fall during summer

Length

• 7–13 cm

Colour

• Upper surface dull dark green
• Lower surface greyish

Margin

• Double-toothed, the largest teeth almost lobe-sized
• Margin clearly rolled under

Buds

Form

• 2 or 3 hairy scales that meet along their edges
• Leaf scars with 3–5 vein scars

Colour

• Green

Twigs

Form

• Moderately stout
• Triangular or round in cross-section
• Pith indistinctly triangular in cross-section

Colour

• Purplish-brown

Flowers

Form

• Pollen catkins in small clusters at the shoot tips
• Seed catkins visible in winter in small lateral clusters

Length

• Pollen catkins about 3 cm in winter, 10–15 cm at pollination
• Seed catkins about 5 mm

Structure

• Monoecious

Fruits

Form

• Mature seed catkins short-stalked, abundant
• Nutlet narrow-winged or encircled by wing

Length

• Mature seed catkins 15–25 mm
• Nutlet about 2 mm

Timing

• Ripen in early autumn, shed in late autumn and into winter

Bark

Form

• Smooth, occasionally shallowly furrowed, with age separates into irregular flat plates

Colour

• Light grey, usually almost white with lichens
• Wounds turn red

Wood

Texture

• Fine, even-textured

Colour

• Light brown, often turns reddish after cutting

Uses

• Wood carving, furniture, firewood

Size

Height

• To 25 m

Diameter

• To 60 cm

Maximum age

• 75 years

Tree form

Forest-grown

Trunk

• Straight, slightly tapered
• Distinct to top of the crown

Crown

• Narrow, rounded

Open-grown

Crown

• Extends to the ground
• Broadly conical

Root system

• Shallow, wide-spreading

Habitat

Site

• Floodplains and along streams

Light tolerance

• Intolerant of shade

Associated species

• In pure stands; also mixed with black cottonwood, grand fir, Douglas-fir, western redcedar, western hemlock, western yew, bigleaf maple, and vine maple

Range

In Canada, a narrow band within 150 km of the Pacific coast; in the United States, the states of Washington and Oregon