Bunchberry • Cornus spp. • Heiltsuk/Haíɫzaqv - ƛṃ́k̓vúlí • Nuxalk - p'qwlht
This entry pertains to C. canadensis (Canadian bunchberry, dwarf dogwood), C. suecica (dwarf bog bunchberry, Lapland cornel, northern bunchberry), and C. unalaschkensis (Alaskan bunchberry, western cordilleran bunchberry), due to the confusion that often results when differentiating between these species as well as some taxonomic confusion resulting from hybrids.
Examples of bunchberry (likely Alaskan bunchberry) with three pairs of terminal whorl leaves. Top left shows a plant with white floral bracts, bottom left displays purple-tipped bracts. Photos by ES 470 participants. Top right: bunchberry growing on a western redcedar trunk. Photo by Helen McConnell. Bottom left: bunchberry fruits. Photo by Kira Hoffman.
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Identification
Bunchberry is a low-growing plant that may trail along the ground or up tree trunks to heights of 25 cm or more. Leaves spread outwards from the stem, usually in a terminal whorl of pairs, creating a base for the single flower-like structure that is actually a dense head of tiny flowers surrounded by four floral bracts. These bracts are usually white or off-white to purple-tinged.
There are three very similar species of bunchberry or dogwood in BC: dwarf dogwood (C. canadensis), Alaskan bunchberry (C. unalaschkensis), and dwarf bog bunchberry (C. suecica). C. canadensis usually has greenish-white flowers, sometimes tinged with purple. It has a terminal whorl of 4-7 short-stalked leaves, with 1-2 pairs of bract-like leaves on the stem below. C. suecia, a red-listed species in BC, has completely or partially dark purple flowers found within the large white bracts. Its leaves are stalkless and occur in a terminal set of 1-3 pairs, with at least one more pair further down the stem.
C. unalaschkensis, a species originally derived from past hybridization between the other two Cornus spp., is even more similar to C. canadensis. Fred Ganders (2010) contends that the two are often mistaken even in the scientific literature. It has leaves like C. canadensis but flowers like C. suecica. Cornus taxonomy is further confused by occasional hybrids of C. canadensis and C. suecica; in such cases the hybrid is usually sterile.
Within-species variation has also been observed in bunchberry fruit shape: some berries are spherical with rather large seeds while others with smaller seeds are elongated into a teardrop shape that is wider at the top (Nancy Turner, personal communication).
Habitat & Range
Bunchberry grows in a variety of habitats from low to subalpine elevations, generally in moist forest, meadows and bogs, and often on trees and fallen woody debris. C. canadensis is common across most of North America, north to the Canadian Territories and south to California, and is also found in eastern Asia. C. unalaschkensis is mostly found in coastal locations from Alaska to California; bunchberry found on Calvert Island has been identified as C. unalaschkensis. C. suecica is rarely found in coastal BC; it is more common in Alaska, and is a circumpolar species.
Intriguing Info
Bunchberry undergoes explosive pollination: its flowers open in under a millisecond, creating enough force to catapult pollen into the air at an initial speed of 4 meters per second, and an acceleration rate of 2400 times that of gravity. See Tale of the Dogwood for more information and video of this remarkable process. The process is also described on NPR's All Things Considered.
iNaturalist
https://www.inaturalist.org/taxa/47192-Cornus-canadensis
https://www.inaturalist.org/taxa/128718-Cornus-%C3%97-unalaschkensis
https://www.inaturalist.org/taxa/134125-Cornus-suecica
Bunchberry is a low-growing plant that may trail along the ground or up tree trunks to heights of 25 cm or more. Leaves spread outwards from the stem, usually in a terminal whorl of pairs, creating a base for the single flower-like structure that is actually a dense head of tiny flowers surrounded by four floral bracts. These bracts are usually white or off-white to purple-tinged.
There are three very similar species of bunchberry or dogwood in BC: dwarf dogwood (C. canadensis), Alaskan bunchberry (C. unalaschkensis), and dwarf bog bunchberry (C. suecica). C. canadensis usually has greenish-white flowers, sometimes tinged with purple. It has a terminal whorl of 4-7 short-stalked leaves, with 1-2 pairs of bract-like leaves on the stem below. C. suecia, a red-listed species in BC, has completely or partially dark purple flowers found within the large white bracts. Its leaves are stalkless and occur in a terminal set of 1-3 pairs, with at least one more pair further down the stem.
C. unalaschkensis, a species originally derived from past hybridization between the other two Cornus spp., is even more similar to C. canadensis. Fred Ganders (2010) contends that the two are often mistaken even in the scientific literature. It has leaves like C. canadensis but flowers like C. suecica. Cornus taxonomy is further confused by occasional hybrids of C. canadensis and C. suecica; in such cases the hybrid is usually sterile.
Within-species variation has also been observed in bunchberry fruit shape: some berries are spherical with rather large seeds while others with smaller seeds are elongated into a teardrop shape that is wider at the top (Nancy Turner, personal communication).
Habitat & Range
Bunchberry grows in a variety of habitats from low to subalpine elevations, generally in moist forest, meadows and bogs, and often on trees and fallen woody debris. C. canadensis is common across most of North America, north to the Canadian Territories and south to California, and is also found in eastern Asia. C. unalaschkensis is mostly found in coastal locations from Alaska to California; bunchberry found on Calvert Island has been identified as C. unalaschkensis. C. suecica is rarely found in coastal BC; it is more common in Alaska, and is a circumpolar species.
Intriguing Info
Bunchberry undergoes explosive pollination: its flowers open in under a millisecond, creating enough force to catapult pollen into the air at an initial speed of 4 meters per second, and an acceleration rate of 2400 times that of gravity. See Tale of the Dogwood for more information and video of this remarkable process. The process is also described on NPR's All Things Considered.
iNaturalist
https://www.inaturalist.org/taxa/47192-Cornus-canadensis
https://www.inaturalist.org/taxa/128718-Cornus-%C3%97-unalaschkensis
https://www.inaturalist.org/taxa/134125-Cornus-suecica
Left: variation in bunchberry fruit shape, from round to teardrop-shaped (red berries). Flowers at right show C. unalaschkensis; the flower at centre is likely C. unalaschkensis as well. Left and right photos were taken in Hartley Bay by Nancy Turner; centre photo taken on Hecate Island by Kelly Fretwell.
References
Cornus canadensis L. In Klinkenberg, Brian. (Ed.). 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 06/03/2013.
Cornus suecica L. In Klinkenberg, Brian. (Ed.). 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 23/02/2015.
Cornus unalaschkensis Ledeb. In Klinkenberg, Brian. (Ed.). 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 06/03/2013.
Pojar, J. and MacKinnon, A. (2005). Plants of Coastal British Columbia, Revised. Vancouver, BC: Lone Pine Publishing. P. 320.
Authors and editors of page
Chanda Brietzke, Kelly Fretwell, Nancy Turner, and Brian Starzomski (2015).
Cornus canadensis L. In Klinkenberg, Brian. (Ed.). 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 06/03/2013.
Cornus suecica L. In Klinkenberg, Brian. (Ed.). 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 23/02/2015.
Cornus unalaschkensis Ledeb. In Klinkenberg, Brian. (Ed.). 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 06/03/2013.
Pojar, J. and MacKinnon, A. (2005). Plants of Coastal British Columbia, Revised. Vancouver, BC: Lone Pine Publishing. P. 320.
Authors and editors of page
Chanda Brietzke, Kelly Fretwell, Nancy Turner, and Brian Starzomski (2015).