Red alder

Alnus rubra
Red alder Red alder

A medium-sized broad-leaf tree, up to 24 metres tall. Trees growing in the forest develop a slightly tapered trunk extending up to a narrow, rounded crown. Trees in the open have crowns that start near the ground giving it a broad cone shape.

Red alder leaves

Bright green above and greyish underneath. They are oval-shaped, with pointed tips, and coarsely toothed edges that tend to curl under. The hair-covered veins form a ladder-like pattern. Leaves stay green until they drop off.
The flowers occur as either male or female clusters. Male flowers are in long, drooping, reddish catkins, and female flowers are in short, woody, brown cones.
Red alder female catkins
Female catkins
Red alder male catkins
Male catkins
The female cones are oval-shaped, 2 centimetres long. The seed is a narrow winged nutlet.
Red alder bark Bark
Thin, greenish on young trees, turning grey to whitish with age. The inner bark and fresh wounds tend to turn deep reddish-orange when exposed to air.

Where to find red alder
It occurs along the entire coast of British Columbia.

Red alder does not tolerate shade and occupies a site quickly after disturbance. It grows rapidly, often shading out conifers such as Douglas-fir. It tends to occur on sites rich in nutrients, including floodplains and streambanks.

Red alder occurs with all of the low elevation coastal tree species, including black cottonwood, grand fir, Douglas-fir, and the cedars. It tends to be associated with a dense layer of shrubs and herbs, including salmonberry, red elderberry, and several ferns.

Where to find red alder
Aboriginal people used the bark for dyeing basket material, wood, wool, feathers, human hair, and skin. Depending on the technique used, the colours ranged from black to brown to orangey-red. Some coastal groups used the tree's inner cambium layer for food. The wood is low in pitch, which makes it a good wood for smoking meat. The wood was also used for carving items such as bowls.Caution

Red alder is used for furniture, flooring, and firewood.

Red alder is short-lived, with an average life span of 40 to 60 years.

It is a nitrogen-fixer, meaning that it puts nitrogen back into the soil, unlike most plants. Small bumps, called nodules, on the roots house an organism that can convert the nitrogen in the soil into a form that plants can absorb. When the nitrogen-rich leaves fall, they provide a nutritious compost on the forest floor.

Previous <<    >> Next