Eriophorum virginicum, the tawny cottongrass, is a species of flowering plant in the sedge family Cyperaceae. It is native to eastern North America but was introduced into British Columbia in western Canada. It is most common in eastern Canada, New England, and the Great Lakes region. It is the only species of Eriophorum in North America that occurs in the southeastern United States, where it is uncommon. The common name refers to the tawny color of its fruiting head. Despite the name, it is a sedge, not a grass, and it is sometimes called tawny cottonsedge to emphasize this fact.

Eriophorum virginicum
Morristown, Vermont, USA (July 25)

Secure  (NatureServe)[1]
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Poales
Family: Cyperaceae
Genus: Eriophorum
Species:
E. virginicum
Binomial name
Eriophorum virginicum
Synonyms[3]
Homotypic synonyms
    • Eriophoropsis virginica (L.) Palla
    • Scirpus virginicus (L.) T.Koyama
Heterotypic synonyms
    • Eriophorum confertissimum Alph.Wood
    • Eriophorum virginianum Houtt.
    • Eriophorum virginicum var. album A.Gray
    • Eriophorum virginicum f. album (A.Gray) Wiegand
    • Eriophorum virginicum var. confertissimum (Alph.Wood) Alph.Wood
    • Eriophorum virginicum var. gracile Torr.

Description

edit

Eriophorum virginicum is a perennial herbaceous plant that forms colonies by means of long-creeping rhizomes. Each stem (or culm) in the colony grows to 120 cm (47 in) long. The terminal inflorescence comprises 2–10 spikelets, each on a peduncle between 2 and 10 mm long. The inflorescence is subtended by 2–5 leaf-like bracts, the longest of which is 4 to 12 cm (2 to 5 in) in length. Individual flowers have 10 or more perianth bristles that are brown in color (at least at the base). Rarely the bristles are entirely white.[4][5]

Typically the fruiting head is densely packed, which tends to obscure the spikelets. Despite this, Eriophorum virginicum is rather easy to distinguish from other cottongrasses due to its late fruiting time and distinctive color.[6]

Taxonomy

edit

Eriophorum virginicum was first described by the Swedish botanist Carl Linnaeus in 1753.[2] Linnaeus based his diagnosis on a specimen collected in Virginia,[7] hence the specific epithet virginicum and the common name Virginia cottongrass.

Eriophorum virginicum was segregated to a new genus Eriophoropsis by the Austrian botanist and mycologist Eduard Palla in 1896.[8] Later, in 1958, it was segregated to the existing genus Scirpus Tourn. ex L. by the Japanese botanist and collector Tetsuo Michael Koyama.[9] As of July 2024, both Eriophoropsis virginica (L.) Palla and Scirpus virginicus (L.) T.Koyama are considered to be synonyms for Eriophorum virginicum L.[10][11]

Eriophorum virginicum var. album was described by the American botanist Asa Gray in 1876.[12] Variety album has white (not brown) bristles. In 1924, the American botanist Karl McKay Wiegand reduced the variety to forma.[13] Both names are considered to be synonyms for Eriophorum virginicum L.

Eriophorum virginicum, together with Eriophorum tenellum and Eriophorum gracile, form a strongly supported clade that is sister to the rest of the genus. The clade is distinguished by having glumes (scales at the base of each flower in a spikelet) with many prominent nerves whereas the glumes of the remaining species possess a single prominent midnerve.[14]

Distribution and habitat

edit

Eriophorum virginicum is native to eastern North America, from Newfoundland and Labrador in Canada to South Carolina in the United States (U.S.), ranging as far west as Minnesota.[3] It was introduced in British Columbia in western Canada.[15] In the U.S., it is most common in New England and the Great Lakes region.[16] It is the only species of Eriophorum in North America that occurs in the southeastern U.S.,[17] where it is least common.

Eriophorum virginicum is an obligate wetland (OBL) species.[18][19] In New England, it prefers bogs, acidic fens, and wet meadows.[20][21]

Ecology

edit

Eriophorum virginicum is a perennial flowering plant that flowers in the early summer. After the flowers are pollinated, cotton-like fruiting heads develop between mid-summer and early autumn.[4] In Minnesota, for example, fruiting occurs from July to September.[22]

Seasonal growth stages

References

edit
  1. ^ "Eriophorum virginicum". NatureServe Explorer. NatureServe. Retrieved 6 July 2024.
  2. ^ a b "Eriophorum virginicum L.". International Plant Names Index (IPNI). Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens. Retrieved 6 July 2024.
  3. ^ a b "Eriophorum virginicum L.". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 6 July 2024.
  4. ^ a b Ball, Peter W.; Wujek, Daniel E. (2002). "Eriophorum virginicum". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 23. New York and Oxford: Oxford University Press. Retrieved 6 July 2024 – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
  5. ^ Gilman (2015), pp. 134–135.
  6. ^ Reznicek, A. A.; Voss, E. G.; Walters, B. S. (February 2011). "Eriophorum". Michigan Flora Online. University of Michigan. Retrieved 8 August 2024.
  7. ^ Linnaeus (1753), pp. 52–53.
  8. ^ "Eriophoropsis virginica (L.) Palla". International Plant Names Index (IPNI). Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens. Retrieved 16 July 2024.
  9. ^ "Scirpus virginicus (L.) T.Koyama". International Plant Names Index (IPNI). Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens. Retrieved 16 July 2024.
  10. ^ "Eriophoropsis virginica (L.) Palla". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 16 July 2024.
  11. ^ "Scirpus virginicus (L.) T.Koyama". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 16 July 2024.
  12. ^ "Eriophorum virginicum var. album A.Gray". International Plant Names Index (IPNI). Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens. Retrieved 29 July 2024.
  13. ^ "Eriophorum virginicum f. album (A.Gray) Wiegand". International Plant Names Index (IPNI). Royal Botanic Gardens, Kew; Harvard University Herbaria & Libraries; Australian National Botanic Gardens. Retrieved 29 July 2024.
  14. ^ Léveillé-Bourret (2018), pp. 28, 35–36, 42.
  15. ^ "Eriophorum virginicum". State-level distribution map from the North American Plant Atlas (NAPA). Biota of North America Program (BONAP). 2014. Retrieved 6 July 2024.
  16. ^ "Eriophorum virginicum". County-level distribution map from the North American Plant Atlas (NAPA). Biota of North America Program (BONAP). 2014. Retrieved 6 July 2024.
  17. ^ "Eriophorum". State-level distribution maps from the North American Plant Atlas (NAPA). Biota of North America Program (BONAP). 2014. Retrieved 6 July 2024.
  18. ^ Lichvar et al. (2016).
  19. ^ "Eriophorum virginicum L.". National Wetland Plant List. U.S. Army Corps of Engineers. Retrieved 10 July 2024.
  20. ^ Haines (2011), pp. 161–162.
  21. ^ "Eriophorum virginicum — tawny cottonsedge". Go Botany. Native Plant Trust. Retrieved 6 July 2024.
  22. ^ "Eriophorum virginicum (Tawny Cottongrass)". Minnesota Wildflowers. Retrieved 6 July 2024.

Bibliography

edit
edit
  • "Eriophorum virginicum". Lady Bird Johnson Wildflower Center. The University of Texas at Austin. Retrieved 6 July 2024.
  • Weakley, Alan S.; Southeastern Flora Team (2024). "Eriophorum virginicum Linnaeus". Flora of the southeastern United States. University of North Carolina Herbarium, North Carolina Botanical Garden. Retrieved 10 July 2024.
  • "Eriophorum virginicum". North Carolina Extension Gardener Plant Toolbox. Retrieved 10 July 2024.
  • "Tawny Cotton Grass". Illinois Wildflowers. Retrieved 10 July 2024.