E-Flora BC: Electronic Atlas of the Flora of British Columbia

Alnus alnobetula subsp. sinuata
Sitka alder
Betulaceae (Birch family)

Introduction to Vascular Plants

Distribution of Alnus alnobetula ssp. sinuata
Click here to view our interactive map and legend

Details about map content are available here
Click on the map dots to view record details.

Species Information

Click on the image below to view an expanded illustration for this species.

Illustration Source: The Illustrated Flora of British Columbia

General:
Deciduous shrub or tree, 1-5 m tall; pointed axillary buds without stalks; bark scaly, sometimes lichen-covered, yellowish-brown or grey.

Leaves:
Alternate, deciduous, smooth, finely toothed 1-2 times, oval with pointed tips, 4-10 cm long, brownish in the fall.

Flowers:
Inflorescence of male and female catkins which open at the same time as the leaves on current year's growth; male catkins unstalked.

Fruits:
Small nutlets, with broad wings; female cones 1.5-2 cm long, egg-shaped.

Notes:
Three subspecies occur in BC.

Source: The Illustrated Flora of British Columbia

Key to the Species and Taxonomic Notes

1. Leaves finely once or twice saw-toothed; axillary buds unstalked, pointed; male catkins unstalked; stalks as long as or longer than the conelike sillicles..........................A. viridis

1. Leaves coarsely to irregularly round-toothed; axillary buds pedunculate, blunt or short-pointed; male catkins stalked; stalks shorter than the conelike silicles

2. Leaf margins rolled under; nutlets with narrow-winged margins.......................................A. rubra

2. Leaf margins not rolled under; nutlets wingless..................................A. incana

Source: Illustrated Flora of British Columbia, Volume 2

Habitat / 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.

Source: The Illustrated Flora of British Columbia

Ecology

Ecological Framework for Alnus alnobetula ssp. sinuata

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
Site Information	Minimum	Average	Maximum
Elevation (metres)	0	1172	2500
Slope Gradient (%)	0	22	205
Aspect (degrees) [0 - N; 90 - E; 180 - S; 270 - W]	0	27	360
Soil Moisture Regime (SMR) [0 - very xeric; 4 - mesic; 8 - hydric]	0	4	8
Modal Nutrient Regime Class	C
Number of field plots species was recorded in:	3292
Modal BEC Zone Class	ESSF
All BEC Zones (# of stations/zone) species was recorded in:	AT(2), BG(4), BWBS(238), CMA(1), CWH(92), ESSF(802), ICH(648), IDF(186), MH(26), MS(580), PP(7), SBPS(16), SBS(575), SWB(2)
Source: Klinkenberg 2020

Status Information

Scientific Name	Origin Status	Provincial Status	BC List (Red Blue List)	COSEWIC
Alnus alnobetula ssp. crispa	Native	S4	Yellow	Not Listed
Alnus alnobetula ssp. fruticosa	Native	S5?	Yellow	Not Listed
Alnus alnobetula ssp. sinuata	Native	S5	Yellow	Not Listed

BC Ministry of Environment: BC Species and Ecosystems Explorer, the authoritative source for conservation information in British Columbia.

Synonyms and Alternate Names

Alnus crispa subsp. laciniata Hultén
Alnus crispa subsp. sinuata (Regel) Hultén
Alnus crispa var. sinuata
Alnus sinuata (Regel) Rydb.
Alnus viridis (Chaix) DC.
Alnus viridis var. sinuata Regel
Duschekia sinuata (Regel) Pouzar

Taxonomic and Nomenclatural Links

Flora North America treatment for Betulaceae
Genetic information (NCBI Taxonomy Database)
International Plant Names Index
Taxonomic Information from the World Flora Online
Integrated Taxonomic Information System

Additional Range and Status Information Links

Burke Museum of Natural History (Washington State records)
CalFlora
Consortium of Pacific Northwest Herbaria records
Jepson Interchange
NatureServe Explorer

Additional Photo Sources

Images From CalPhoto
UT Austin's Native Plant Database
Google Image Search
Flickr Image Search

General References

Google Scholar Search
Family References
General Botanical References for BC

Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2020. E-Flora BC: Electronic Atlas of the Plants of British Columbia [eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 2024-12-07 7:50:45 AM ]

Disclaimer: The information contained in the E-Flora atlas pages is derived from expert sources as cited in each section. This information is scientifically based. E-Flora also acts as a portal to other sites via deep links. As always, users should refer to the original sources for complete information. E-Flora BC is not responsible for the accuracy or completeness of the original information.