Alnus viridis ssp. sinuata
Alnus viridis (Chaix) DC. ssp. sinuata (Regel) Á. Löve & D. Löve
Sitka Alder, Mountain Alder
Betulaceae (Birch Family)
Synonym(s): Alnus alnobetula, Alnus crispa ssp. laciniata, Alnus crispa ssp. sinuata, Alnus sinuata, Alnus viridis var. sinuata, Duschekia sinuata
USDA Symbol: ALVIS
A thicket-forming shrub, usually 10-15 ft. tall, with short, nearly horizontal branches forming a narrow crown. The shiny, oval, toothed leaves and catkins develop with the leaves on growth of the current season. Bark is reddish-brown, becoming gray-black.
In Alaska, Sitka Alder is a pioneer in disturbed areas, following landslides, logging, and glacial retreat. Adapted to soils too barren for other trees, this subspecies improves soil conditions by adding organic matter and nitrogen from bacteria in its root nodules. It acts as a short-lived nurse tree for Sitka Spruce (Picea sitchensis), later dying when shaded by the larger conifer.
From the Image Gallery
Plant CharacteristicsDuration: Perennial
Leaf Retention: Deciduous
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Shape: Ovate
Leaf Venation: Pinnate
Leaf Margin: Double-serrate
Leaf Texture: Papery
Breeding System: Flowers Unisexual , Monoecious
Fruit Type: Samara
Size Notes: Up to about 30 feet tall, often much shorter.
Leaf: Green to yellow-green above and paler green below.
Autumn Foliage: yes
Fruit: Brown cone-like, 1/2 to 1 inch long.
Bloom InformationBloom Color: Green , Brown
Bloom Time: Mar , Apr , May , Jun , Jul , Aug
DistributionUSA: AK , CA , ID , MT , OR , WA , WY
Canada: AB , BC
Native Distribution: AK to n. CA & through the Rockies to WY
Native Habitat: Moist woods; stream banks; pond margins; open, mt. slopes
Growing ConditionsWater Use: High
Light Requirement: Sun , Part Shade , Shade
Soil Moisture: Moist
CaCO3 Tolerance: Low
Soil Description: Moist soils.
Conditions Comments: Useful in erosion control. Alders fix nitrogen and thus serve as nutrient-giving pioneers in reclamation projects.
PropagationDescription: Propagated from freshly collected seeds released from the female conelets in fall.
Seed Treatment: If seeds have dried in storage, a cool-moist stratification at 41 degrees for 180 days will be necessary.
Commercially Avail: yes
Find Seed or Plants
Find seed sources for this species at the Native Seed Network.
From the National Organizations DirectoryAccording to the species list provided by Affiliate Organizations, this plant is on display at the following locations:
Native Seed Network - Corvallis, OR
Web ReferenceWebref 30 - Calflora (2018) Calflora
Webref 3 - Flora of North America (2014) Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
Additional resourcesUSDA: Find Alnus viridis ssp. sinuata in USDA Plants
FNA: Find Alnus viridis ssp. sinuata in the Flora of North America (if available)
Google: Search Google for Alnus viridis ssp. sinuata
MetadataRecord Modified: 2022-09-27
Research By: TWC Staff