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 subsp. sinuata
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Species Information

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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

Habitat / Range

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

Synonyms and Alternate Names

Taxonomic and Nomenclatural Links

Additional Range and Status Information Links

Additional Photo Sources

General References

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: 2025-04-17 4:37:06 AM ]

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