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

Cornus unalaschkensis Ledeb.
Alaskan bunchberry
Cornaceae (Dogwood family)

Introduction to Vascular Plants

© Brian Klinkenberg  Email the photographer   (Photo ID #20321)

E-Flora BC Static Map
Distribution of Cornus unalaschkensis
Click here to view the full interactive map and legend
Details about map content are available here
New! Click on the map dots to view record details.

Introduction

Cornus unalaschkensis (Alaskan bunchberry) is a small dogwood species that is found along the Pacific Coast in North America (BC, AK, CA, ID, OR, WA) (USDA 2010). In British Columbia, it is primarily coastal in distribution. Plants in the Fraser Valley are considered to be this species. Alaskan bunchberry flowers in our region from June through August at higher elevations.

Species description: Perennial herb. Stem erect, < 20 cm. Leaves 2-8 cm, elliptic to ovate, glabrous or hairy, in a whorl of 4-6 below inflorescence, plus a pair of small ones near the middle of the stem. Inflorescence head-like, 2-4 cm wide, surrounded by 4 conspicuous white, petal-like bracts, 0.8-2.0 mm. Sepals 0.4 mm, petals 1.5 mm, white with purple tips. Fruit a drupe, spherical, 6-8 mm, red, stone smooth. Habitat moist forest and bogs.

Commonly confused with C. canadensis, even in the scientific literature, this is a distinct species. It is an allopolyploid, derived by chromosome doubling in a hybrid of C. canadensi and C. suecica, and apparently originated before the last glaciation. Cornus canadensis differs in having white petals, and the pair of stem leaves are bract-like, < 1 cm long. This is an excellent ornamental.

Note Author: Fred Ganders, 2010

Additional Notes

The geographical range of western bunchberry is almost completely separate from its two parent species, being south of that of northern bunchberry and west and south of that of Canada bunchberry. However, the ranges of northern bunchberry and Canada bunchberry overlap north of the Alaska panhandle, and hybrids between these two species have been found there. These hybrids look like western bunchberry, but they are diploid (no chromosome doubling having occurred) and mostly sterile; only about half their pollen is viable, and they rarely set seed. Current hybridization between the two parent species takes place outside the present range of western bunchberry and apparently has not yet led to the production of allotetraploids there. The hybridization and allopolyploidy that produced western bunchberry took place sometime before the last glaciation, and the tetraploids survived farther south than the parent species and subsequently recolonized an area where the parents had not occurred or had been eliminated.

Source: Extracted from Wildflower Genetics, A Field Guide for British Columbia and the Pacific Northwest (1983), with permission.

Synonyms and Alternate Names

Chamaepericlymenum unalaschkense (Ledeb.) Rydb.

Taxonomic and Nomenclatural Links

Additional Photo Sources

Related Databases

Species References

Ganders, Fred R. 2010. Notes on Cornus unalaschkensis. Unpublished manuscript.

Griffiths, Anthony J. F. and Fred R. Ganders. 1983. Wildflower Genetics: A Field Guide for British Columbia and the Pacific Northwest. Flight Press, Vancouver, BC.

General References