Host an Event Volunteer Join Tickets

Support the plant database you love!


Plant Database

Search for native plants by scientific name, common name or family. If you are not sure what you are looking for, try the Combination Search or our Recommended Species lists.

Enter a Plant Name:
Or you can choose a plant family:

Alnus rubra

Alnus rubra Bong.

Red Alder, Western Alder

Betulaceae (Birch Family)

Synonym(s): Alnus oregona, Alnus oregona var. pinnatisecta

USDA Symbol: alru2

USDA Native Status: L48 (N), AK (N), CAN (N)

Graceful tree with straight trunk, pointed or rounded crown, and mottled, light gray to whitish, smooth bark. Alder roots, like those of legumes, often have swellings or root nodules containing nitrogen-fixing bacteria, which enrich the soil by converting nitrogen from the air into chemicals like fertilizers that the plants can use. The common name describes the reddish-brown inner bark and heartwood.


From the Image Gallery

No images of this plant

Plant Characteristics

Duration: Perennial
Habit: Tree
Leaf Retention: Deciduous
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Shape: Elliptic , Ovate
Leaf Venation: Pinnate
Leaf Margin: Double-serrate
Breeding System: Flowers Unisexual , Monoecious
Inflorescence: Catkin
Fruit Type: Samara
Size Notes: Height 20-40 feet, spread 20-30 feet.
Leaf: Dark green above.
Fruit: Cone-like, 1/2 to 1 inch long.

Bloom Information

Bloom Color: Red , Green , Brown
Bloom Time: Mar , Apr


USA: AK , CA , ID , OR , WA
Canada: BC
Native Distribution: SE. Alaska southeast to central California; also local in N. Idaho; to 2500' (762 m).
Native Habitat: Moist soils including loam, gravel, sand, and clay, along streams and lower slopes; often in nearly pure stands.

Growing Conditions

Water Use: High
Light Requirement: Sun , Part Shade , Shade
Soil Moisture: Moist
CaCO3 Tolerance: Low


Use Food: Used in smoking meats and fish.
Use Other: Furniture, veneer, cabinets. Bark was used by Indians for dyes.
Interesting Foliage: yes
Attracts: Birds


Propagation Material: Seeds , Softwood Cuttings
Seed Treatment: Best germination in full sun.
Maintenance: Can be shaped by pruning when young.

Find Seed or Plants

Find seed sources for this species at the Native Seed Network.

View propagation protocol from Native Plants Network.

National Wetland Indicator Status

This information is derived from the U.S. Army Corps of Engineers National Wetland Plant List, Version 3.1 (Lichvar, R.W. 2013. The National Wetland Plant List: 2013 wetland ratings. Phytoneuron 2013-49: 1-241). Click here for map of regions.

From the National Organizations Directory

According to the species list provided by Affiliate Organizations, this plant is on display at the following locations:

Native Seed Network - Corvallis, OR


Bibref 1149 - Alaska Trees And Shrubs (2007) Viereck, L. A. and Little, E. L.
Bibref 698 - Native Plants for Use in the California Landscape (1978) Labadie, E. L.

Search More Titles in Bibliography

Additional resources

USDA: Find Alnus rubra in USDA Plants
FNA: Find Alnus rubra in the Flora of North America (if available)
Google: Search Google for Alnus rubra


Record Modified: 2009-01-29
Research By: TWC Staff

Go back