Sitka Alder vs Red Alder - TreeTime.ca

Sitka Alder vs Red Alder

Alnus alnobetula subsp. sinuata

Alnus rubra

CUSTOM GROW

CUSTOM GROW

Sitka Alder
Red Alder

Sitka Alder is a native deciduous shrub or small tree that often forms dense thickets. Its extensive root system stabilizes slopes and streambanks. Nitrogen-fixing capabilities and nutrient-rich leaf litter improve soil fertility, creating better growing conditions for surrounding plants. These qualities make it especially effective in disturbed or erosion-prone sites.
Often found in moist, high-elevation mountain environments, Sitka Alder also enhances habitat by providing cover and structure in both riparian and upland areas. Birds and small mammals utilize it for nesting, and its seeds serve as a food source.
Note: We use Sitka Alder for Alnus alnobetula subsp. sinuata. This species is also known by many other common names, including Mountain Alder, Green Alder, and others. Please confirm the scientific name to ensure you are ordering the correct plant.

Red Alder is a fast-growing deciduous tree native to western North America. Its fixes nitrogen, which enriches soils and supports the growth of surrounding plants. Ideal for sites with poor soil conditions, or areas disturbed by logging, construction or fire.
It provides shade in riparian areas, creating cover for fish. Its seeds and buds are eaten by birds and small mammals, while the foliage provides browse for wildlife. The catkins release clouds of pollen attracting bees and other insects.
The Red Alder gets its namesake from the rusty-red color the bark turns when bruised.

Sitka Alder Quick Facts

Red Alder Quick Facts

Zone: 2a
Zone: 5b
Height: 5 m (15 ft)
Height: 15 m (50 ft)
Spread: 3 m (10 ft)
Spread: 9 m (30 ft)
Light: partial shade, full sun
Light: partial shade, full sun
Moisture: wet
Moisture: normal, wet
Growth rate: medium
Growth rate: fast
Life span: medium
Life span: medium
Growth form: upright to prostrate, thicket-forming
Growth form: upright, rounded to conical
Spreading: seed - medium, layering - medium
Spreading: seeds - medium, stump sprouting - medium


Bark: redish-brown to grey, smooth
Bark: smooth, grey
Hybrid: no
Hybrid: no
Catkins: yes
Catkins: yes


Native to: AB, BC, YT, NT
Native to: BC
Other Names: wavy leaf alder
Other Names: oregon alder, pacific coast alder, western alder