Red Alder (Alnus rubra), Birch Family (Betulaceae) 

Description

The trunk on this tree grows straight and develops a rounded crown. This tree lives in moist soils along streams or lower slopes. I found this one on a path not far from the river.

Bark

The bark is smooth, gray and beautifully mottled with white patches that remind me of little clouds.

Leaves

The leaves are ovate to elliptical, wavy-lobed and doubly saw-toothed. They are 3” - 6” long and 1.75” - 3” wide. A distinguishing characteristic is that the edges of the leaf are slightly rolled under (revolute) which creates a small, green rim on the underside of the leaf. The leaves have nearly straight, parallel veins that are distinctly seen on both sides of the leaf. The leaves are dark green above and lighter below with small hairs.

Cones

The cones are elliptical and about .5” - 1” long. The cones are on short stalks and turn brown and woody. The seeds are oval, winged nutlets. I’ve seen chickadees poking around these cones presumably eating the seeds.

References

National Audubon Society Field Guide to North American Trees - Western Region, Knopf, 1998. pp. 377 - 378.
Trees to Know in Oregon, Oregon State University Extension Service, Revised April 2005. pp. 64 - 65.
Oregon State University - Oregon Wood Innovation Center - Red Alder (website).

Quick Reference:

Height: 40 - 100’
Leaves: Ovate to elliptical, doubly saw-toothed
Fruit: Woody, brown cones, approx. 1”
Habitat: Moist soils along streams and slopes

Photo Location:
Mt. Pisgah Arboretum
Mt. Pisgah Arboretum Plant List
Eugene, OR