Eriophorum viridicarinatum

Eriophorum viridicarinatum is a species of sedge known by the common names thinleaf cottonsedge, green-keeled cottongrass, and bog cottongrass. It is native to Canada and the United States.

Eriophorum viridicarinatum
Conservation status
Secure  (NatureServe)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Monocots
Clade:	Commelinids
Order:	Poales
Family:	Cyperaceae
Genus:	Eriophorum
Species:	E. viridicarinatum
Binomial name
Eriophorum viridicarinatum (Engelm.) Fernald[2]
Synonyms[3]
Eriophorum latifolium var. viridicarinatum Engelm.

Description

Eriophorum viridicarinatum is a perennial sedge that forms tufts of stiff, erect stems, sometimes just a single stem, and basal leaves up to 30 centimeters long. It grows from a rhizome. The inflorescence is accompanied by two to four leaflike bracts each a few centimeters long. There are up to 30 spikelets, increasing in size as the fruit develops, reaching 3 centimeters in length. Each flower has a tuft of white or brown bristles that are long and cottony, measuring up to 2.5 centimeters long.^[4][5]

Taxonomy

Eriophorum viridicarinatum was first described as the variety Eriophorum latifolium var. viridicarinatum by the German-American botanist Georg Engelmann in 1844.^[6] Engelmann's description was based on specimens collected in Massachusetts and Ohio.^[7] (The name published by Engelmann was hyphenated, as in viridi-carinatum, but the orthographical variant viridicarinatum is now widely used instead.) The American botanist Merritt Lyndon Fernald raised the variety to species rank in 1905.^[8] As of September 2024^[update], Eriophorum viridicarinatum (Engelm.) Fernald is a widely accepted name.^{[3][9][10][11]}

Distribution and habitat

Eriophorum viridicarinatum is native to northern North America, where it occurs in Alaska and throughout much of Canada, its range extending into the northern contiguous United States.^[3][11][12] It is widespread in eastern Canada, with spotty distribution in western Canada and Alaska.^[1] In the United States, it is most common in western Montana, the Great Lakes region, and New England.^[13]

Eriophorum viridicarinatum is an obligate wetland (OBL) species.^[14][15] Throughout its range, it occurs in marshes, wet meadows, bogs, fens, and wet woodlands, at altitudes up to 6,600 feet (2,000 m).^[5] In the Pacific Northwest, British Columbia, Montana, and Wyoming, it typically occurs in montane and alpine zones.^[4] In New England, it prefers fens and high-pH meadows.^[16][17] It is a strict calciphile in Michigan, Pennsylvania, and Vermont,^[18][19] but its habitat broadens further north into Canada.^[20]