Alnus viridis subsp. crispa (Chaix) DC. (Aiton) Turrill
green alder (mountain alder)
Betulaceae (Birch family)

Introduction to Vascular Plants


© Virginia Skilton     (Photo ID #34074)


E-Flora BC Static Map

Distribution of Alnus viridis subsp. crispa
Click here to view the full interactive map and legend

Species Information

Deciduous shrub or tree, 1-5 m tall; pointed axillary buds without stalks; bark scaly, sometimes lichen-covered, yellowish-brown or grey.
Alternate, deciduous, smooth, finely toothed 1-2 times, oval with pointed tips, 4-10 cm long, brownish in the fall.
Inflorescence of male and female catkins which open at the same time as the leaves on current year's growth; male catkins unstalked.
Small nutlets, with broad wings; female cones 1.5-2 cm long, egg-shaped.
Two subspecies occur in BC:

1. Leaf margins shallowly lobed as well as finely saw-toothed..................... ssp. sinuata (Regel) A.& D. Love

1. Leaf margins not at all or only slightly lobed, mostly merely finely saw-toothed..................... ssp. crispa [Ait.] Turrill

SourceThe Illustrated Flora of British Columbia


If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

USDA Species Characteristics

Flower Colour:
Blooming Period:
Fruit/Seed characteristics:
Colour: Brown
Present from Summer to Fall
Source:  The USDA


Ecological Framework for Alnus viridis ssp. crispa

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres)
924 10 2094
Slope Gradient (%)
14 0 83

Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]

338 0 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
4 0 7
Modal Nutrient Regime
# of field plots
 species was recorded in:
Modal BEC Zone Class

All BEC Zones (# of stations/zone) species was recorded in

BWBS(55), CWH(24), ESSF(58), ICH(47), IDF(4), MS(17), SBPS(3), SBS(124), SWB(3)

Habitat and Range

Moist slopes, streambanks, avalanche tracks, bogs and fens in all zones; ssp. crispa frequent in N BC, ssp. sinuata common throughout S BC, becoming less frequent and transitional to ssp. crispa in N BC; circumboreal, E to PQ and S to NC, MN, CO and CA.

SourceThe Illustrated Flora of British Columbia


Synonyms and Alternate Names:
Alnus hultenii Murai p.p.
Alnus hultenii Murai p.p.
Alnus crispa (Aiton) Pursh
Alnus crispa subsp. crispa
Alnus crispa var. elongata Raup
Alnus crispa var. mollis (Fern.) Fern.
Alnus viridis subsp. fruticosa (Rupr.) Nyman
Alnus viridis var. crispa (Aiton) House
Duschekia viridis (Chaix) Opiz p.p.