Cornus canadensis

Cornus canadensis is a species of flowering plant in the dogwood family Cornaceae, native to eastern Asia and North America.[2] Common names include Canadian dwarf cornel, Canadian bunchberry, quatre-temps, crackerberry, and creeping dogwood.[3][4] Unlike its relatives, which are for the most part substantial trees and shrubs, C. canadensis is a creeping, rhizomatous perennial growing to about 20 centimetres (8 inches) tall.

Cornus canadensis
CanadianDogwoodGrowingTrailSide cropped.jpg
Growing at Elfin Lakes, British Columbia

Secure (NatureServe)[1]
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Cornales
Family: Cornaceae
Genus: Cornus
Subgenus: Cornus subg. Arctocrania
Species:
C. canadensis
Binomial name
Cornus canadensis

DescriptionEdit

Cornus canadensis is a slow-growing herbaceous perennial growing 10–20 centimetres (4–8 inches) tall, generally forming a carpet-like mat. The above-ground shoots rise from slender creeping rhizomes that are placed 2.5–7.5 cm (1–3 in) deep in the soil, and form clonal colonies under trees. The vertically produced above-ground stems are slender and unbranched. Produced near the terminal node, the leaves are shiny dark green and arranged oppositely on the stem, clustered with six leaves that often seem to be in a whorl because the internodes are compressed. The leaves consist of two types: two larger and four smaller leaves; the smaller ones develop from the axillary buds of the larger leaves. The leaves have petioles 2 to 3 millimetres (332 to 18 in) in length and leaf blades that are obovate. The blades have entire margins and are 3.5 to 4.8 cm (1+12 to 2 in) long and 1.5 to 2.5 cm (12 to 1 in) wide, with 2–3 veins, cuneate shaped bases and abruptly acuminate apexes. In autumn, the leaves have red-tinted veins and turn completely red.

FlowersEdit

 
Mature and immature flowers, Bonnechere Provincial Park, Ontario

In late spring to midsummer, white flowers are produced that are 2 cm (2532 inch) in diameter with reflexed petals that are ovate-lanceolate in shape and 1–2 cm (13322532 inch) long.[5] The inflorescences are made up of compound terminal cymes, with large showy white bracts that resemble petals. The bracts are green when immature. The bracts are broadly ovate and 0.8 to 1.2 cm (516 to 12 inch) long and 0.5 to 1.1 cm (316 to 716 inch) wide, with 7 parallel running veins. The lower nodes on the stem have greatly reduced rudimentary leaves. The calyx tube is obovate in shape and 1 mm long, covered with densely pubescent hairs along with grayish white appressed trichomes. Stamens are very short, being 1 mm long. The anthers are yellowish white in color, narrowly ovoid in shape. The styles are 1 mm long and glabrous. Plants are for the most part self-sterile and dependent on pollinators for sexual reproduction. Pollinators include bumblebees, solitary bees, beeflies, and syrphid flies.[6] The fruits look like berries but are drupes.

Pollen releaseEdit

Each flower has highly elastic petals that flip backward, releasing springy filaments that are cocked underneath the petals. The filaments snap upward flinging pollen out of containers hinged to the filaments. The stamens accelerate at a rate of 24,000 m/s2.[7] The motion, which can be triggered by pollinators, takes place in less than half a millisecond. The bunchberry has one of the fastest plant actions found so far requiring a camera capable of shooting 10,000 frames per second to catch the action.[8][9]

FruitEdit

 
Immature flowers
 
Fruit

The drupes are green, globose in shape, turning bright red at maturity in late summer; each fruit is 5 mm in diameter and contains typically one or two ellipsoid-ovoid shaped stones. The fruits come into season in late summer.[10] The large seeds within are somewhat hard and crunchy.

TaxonomyEdit

While distinctive as a species itself, the generic placement of these plants has differed in various botanical treatments. When the genus Cornus is taken broadly, as done here, this species is Cornus canadensis, and is included in the subgenus Arctocrania.[11] However, if Cornus is treated in a narrower sense, excluding this species, it can instead be classified as Chamaepericlymenum canadense or as Cornella canadensis.[12][13]

Where C. canadensis, a forest species, and Cornus suecica, a bog species, grow near each other in their overlapping ranges in Alaska, Labrador, and Greenland, they can hybridize by cross-pollination, producing plants with intermediate characteristics.[14][15]

Distribution and habitatEdit

Its native distribution includes Japan, North Korea, northeastern China (Jilin Province), the Russian Far East, the northern United States, Colorado, New Mexico, Canada and Greenland.[3]

Cornus canadensis is a mesophytic species that needs cool, moist soils. It inhabits montane and boreal coniferous forests, where it is found growing along the margins of moist woods, on old tree stumps, in mossy areas, and among other open and moist habitats.[16][17]

EcologyEdit

Birds are the main dispersal agents of the seeds, feeding on the fruit during their fall migration. In Alaska, bunchberry is an important forage plant for mule deer, black-tailed deer and moose, which eat it throughout the growing season.[18]

UsesEdit

It is used as ornamental groundcover in gardens. It prefers moist acidic soil.[19]

The fruits are edible raw but have little flavor.[10][4] The pulp does not easily separate from the seeds. The berries can be cooked, strained, and combined with other fruits or used for pudding.[20]

CultureEdit

Claire Waight Keller included the plant to represent Canada in Meghan Markle's wedding veil, which included the distinctive flora of each Commonwealth country.[21]

ReferencesEdit

  1. ^ "Cornus Canadensis". NatureServe Explorer. NatureServe. Retrieved 2018-04-01.
  2. ^ RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 978-1405332965.
  3. ^ a b "Cornus canadensis". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA).
  4. ^ a b Peterson, Lee Allen (1978). A Field Guide to Edible Wild Plants of Eastern and Central North America. Boston: Houghton Mifflin. p. 20. ISBN 0-395-20445-3. OCLC 3541725.
  5. ^ Murrell, Zack E.; Poindexter, Derick B. (2016). "Cornus canadensis". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 12. New York and Oxford – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
  6. ^ Barrett, Spencer C.; Helenurm, Kaius. 1987. The reproductive biology of boreal forest herbs. I. Breeding systems and pollination. Canadian Journal of Botany. 65: 2036-2046.
  7. ^ Walker, Marilyn (2008). Wild plants of Eastern Canada : identifying, harvesting and using : includes recipes & medicinal uses. Halifax, N.S.: Nimbus Pub. ISBN 9781551096155. OCLC 190965401.
  8. ^ Edwards, Joan; Whitaker, Dwight; Klionsky, Sarah; Laskowski, Marta J. (2005). "Botany: a record-breaking pollen catapult". Nature. 435 (7039): 164. Bibcode:2005Natur.435..164E. doi:10.1038/435164a. PMID 15889081. S2CID 4412631.
  9. ^ Edwards, Joan; Smith, Gordon P.; McEntee, Molly H.F. (2015). "Long-term time-lapse video provides near complete records of floral visitation" (PDF). Journal of Pollination Ecology. 16 (13): 91–100. doi:10.26786/1920-7603(2015)16. Retrieved 20 December 2021.
  10. ^ a b Lyons, C. P. (1956). Trees, Shrubs and Flowers to Know in Washington (1st ed.). Canada: J. M. Dent & Sons. pp. 111, 196.
  11. ^ Murrell, Zack E.; Poindexter, Derick B. (2016). "Cornus subg. Arctocrania". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 12. New York and Oxford – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
  12. ^ Eyde, R. H. 1987. The case for keeping Cornus in the broad Linnaean sense. Systematic Botany. 12(4): 505-518.
  13. ^ Eyde, Richard H. 1988. Comprehending Cornus: puzzles and progress in the systematics of the dogwoods. Botanical Review. 54(3): 233-351.
  14. ^ Neiland, Bonita J. 1971. The forest-bog complex of southeast Alaska. Vegetatio. 22: 1-64.
  15. ^ Murrell, Zack E. 1994. Dwarf dogwoods: Intermediacy and the morphological landscape. Systematic Botany 19: 539-556.
  16. ^ "Cornus canadensis - Plant Finder". www.missouribotanicalgarden.org.
  17. ^ "Lady Bird Johnson Wildflower Center - The University of Texas at Austin". www.wildflower.org.
  18. ^ Hanley, Thomas A.; Cates, Rex G.; Van Horne, Beatrice; McKendrick, Jay D. 1987. Forest stand-age related differences in apparent nutritional quality of forage for deer in southeastern Alaska. In: Provenza, Frederick D.; Flinders, Jerran T.; McArthur, E. Durant, compilers. Proceedings--symposium on plant-herbivore interactions; 1985 August 7–9; Snowbird, UT. Gen. Tech. Rep. INT-222. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station: 9-17.
  19. ^ "Cornus canadensis". RHS. Retrieved 7 September 2021.
  20. ^ Elias, Thomas S.; Dykeman, Peter A. (2009) [1982]. Edible Wild Plants: A North American Field Guide to Over 200 Natural Foods. New York: Sterling. p. 143. ISBN 978-1-4027-6715-9. OCLC 244766414.
  21. ^ "The Wedding Dress, Bridesmaids' Dresses and Page Boys' Uniforms". 2018-05-19.

External linksEdit