Eriophorum

Eriophorum is a genus of flowering plants in the family Cyperaceae, the sedge family. They are found in the cool temperate, alpine, and Arctic regions of the Northern Hemisphere, primarily in the middle latitudes of North America, Europe, and Asia.

Description

Eriophorium species are perennial herbaceous plants that persist by means of underground rhizomes. Stems grow singly or in clumps. Both basal leaves and stem leaves are present, although the latter are bladeless in some species. The terminal inflorescence is either a single erect spikelet or multiple spikelets on peduncles of various lengths. In the case of multiple spikelets, the inflorescence is subtended by one or more leaf-like bracts. Individual flowers have 10 or more smooth perianth bristles that greatly elongate and remain attached to the achene during fruiting. The bristles facilitate seed dispersal by wind. In cold Arctic regions, the bristles also serve as insulation by trapping solar radiation and thereby increasing the temperature of the reproductive organs.
Identification keys often begin with a pair of alternatives that implicitly divide the genus into two mutually exclusive sections:

Eriophorum section Vaginata: one spikelet, without involucral bracts
Eriophorum section Phyllanthela: multiple spikelets, subtended by one or more leaf-like bracts

Besides the number of spikelets and the presence of bracts, other characters may be used for identification, including: the length of the uppermost leaf blade relative to its sheath; the number of bracts ; the length and orientation of the bracts; the length of the peduncles; and the color of the bristles.

Taxonomy

In the first edition of Species Plantarum published in 1753, the Swedish botanist Carl Linnaeus established genus Eriophorum by recognizing four species: Eriophorum vaginatum, Eriophorum polystachion, Eriophorum virginicum, and Eriophorum alpinum. In the second edition published in 1762, Linnaeus added a fifth species, Eriophorum cyperinum. The name Eriophorum is the primary generic name in use today. Although the names of some of the species have changed, the number of recognized taxa in genus Eriophorum has remained more-or-less the same since 1994.
In the fifth edition of Genera Plantarum published in 1754, Linnaeus referenced the prior work of the Italian botanist Pier Antonio Micheli and the French botanist Joseph Pitton de Tournefort. In 1729, Micheli described genus Linagrostis, including an illustration of an unidentified plant. Tournefort coined the French name Linaigrette in 1694, but his contribution became better known in Europe when his book was translated to Latin in 1719.
The French naturalist and mineralogist Jean-Étienne Guettard resurrected the pre-Linnaean name Linagrostis in 1750, and again in 1754, but Linagrostis is regarded as a synonym for Eriophorum After Guettard, the name Linagrostis was redescribed by numerous botanists, including John Hill, Johann Gottfried Zinn, and Giovanni Antonio Scopoli, but all three published illegitimate names since Linagrostis takes precedence. Scopoli's description of Linagrostis is notable, however, since it is explicitly based on the early work of Tournefort. The names Linagrostis vaginata, Linagrostis alpina, and Linagrostis polystachia are synonyms for the corresponding names introduced by Linnaeus in 1753.
The Austrian botanist and mycologist Eduard Palla established genus Eriophoropsis in 1896 by segregating Eriophorum virginicum into a new genus. The name Eriophoropsis is both a synonym for Eriophorum and the basionym of Eriophorum subgen. Eriophoropsis, the latter described by the Canadian botanist Louis-Florent-Marcel Raymond in 1954.

Species

, the following species are accepted by Plants of the World Online :

Name/Author	Year described	Year published	Group	Distribution
Eriophorum angustifolium Honck.	1782	1782	Multispicate	Widespread across Europe, Asia, North America
Eriophorum arcticum Schekhovts.	1994	2023	Unispicate	Siberia
Eriophorum brachyantherum Trautv. & C.A.Mey.	1856	1856	Unispicate	Scandinavia, northern Russia, Mongolia, Korea, Alaska, northern Canada
Eriophorum callitrix Cham. ex C.A.Mey.	1831	1831	Unispicate	Siberia, Russian Far East, Alaska, Canada, Greenland, Montana, Wyoming
Eriophorum chamissonis C.A.Mey.	1831	1831	Unispicate	Siberia, Russian Far East, Korea, Mongolia, Alaska, Canada, Greenland, northern and western United States
Eriophorum gracile Roth	1799	1799	Multispicate	Much of Europe; northern and Central Asia; China, Tibet, Mongolia, Alaska, Canada, northern United States
Eriophorum humile Turcz.	1838	1838	Unispicate	Altai, Tuva, Kazakhstan, Mongolia, Amur
Eriophorum latifolium Hoppe	1800	1800	Multispicate	Much of Europe; Caucasus, Turkey, Mongolia
Eriophorum scheuchzeri Hoppe	1800	1800	Unispicate	Much of Europe; northern and Central Asia including Siberia, Xinjiang, Himalayas, Alaska, Greenland, Canada, mountains of western United States
Eriophorum tenellum Nutt.	1818	1818	Multispicate	Eastern Canada and northeastern United States from Nunavut and Labrador to New Jersey
Eriophorum tolmatchevii M.S.Novos.	1994	1994	Unispicate	Krasnoyarsk, Yakutiya
Eriophorum transiens Raymond	1959	1959	Multispicate	Guizhou
Eriophorum triste Hadac & Á.Löve	1869	1950	Multispicate	Finland, North America and temperate regions of Asia
Eriophorum vaginatum L.	1753	1753	Unispicate	Most of genus range
Eriophorum virginicum L.	1753	1753	Multispicate	Eastern North America from Labrador to Tennessee, west to Michigan
Eriophorum viridicarinatum Fernald	1844	1905	Multispicate	Canada including Arctic territories; northern United States

The following natural hybrids are also accepted by POWO:

Name/Author	Year described	Year published	Distribution
Eriophorum × beringianum Raymond	1957	1957	Alaska including Aleutians; Magadan region of Russia
Eriophorum × churchillianum Lepage	1957	1957	Alaska
Eriophorum × fellowsii M.S.Novos.	1905	1995	Ontario, Maine, Massachusetts
Eriophorum × gracilifolium M.S.Novos.	1994	1994	European Russia
Eriophorum × medium Andersson	1857	1857	Scattered locations in Finland, Norway, Russia, Alaska, Quebec, Labrador
Eriophorum × pylaieanum Raymond	1951	1951	Scattered locations in Canada and Alaska
Eriophorum × rousseauianum Raymond	1950	1950	Alaska, Quebec

World Flora Online accepts all of the above species and hybrids except Eriophorum arcticum. In addition, WFO accepts Eriophorum × polystachiovaginatum whereas POWO does not.

Other names

Of the five species described by Linnaeus in 1753 and 1762, three of the names are no longer in use. Eriophorum polystachion is a rejected name, now considered to be a synonym for Eriophorum angustifolium subsp. angustifolium, while Eriophorum alpinum and Eriophorum cyperinum are synonyms for Trichophorum alpinum and Scirpus cyperinus, respectively.
The Swedish mycologist and botanist Elias Magnus Fries described Eriophorum russeolum in 1836. Some authors consider Eriophorum russeolum to be a synonym for Eriophorum chamissonis, while others consider the two names to refer to separate species.
In 1942, the American agrostologist and botanist Alan Ackerman Beetle placed the species Scirpus criniger into genus Eriophorum. In 2012, Eriophorum crinigerum was segregated into genus Calliscirpus, and so Eriophorum crinigerum is a synonym for Calliscirpus criniger.
In 1957, the Canadian botanist Louis-Florent-Marcel Raymond placed the species Scirpus scabriculmis into genus Eriophorum. In 2019, Eriophorum scabriculme was segregated into genus Trichophorum. Hence Eriophorum scabriculme is a synonym for Trichophorum scabriculme.
The invalidly published name Eriophorum × polystachiovaginatum is a synonym for Eriophorum × beauverdii but the latter is unplaced by POWO.

Subdivision

In 1849, the Swedish botanist Nils Johan Andersson placed the European species of Eriophorum into two new sections:
Eriophorum section Vaginata:

Eriophorum vaginatum
Eriophorum capitatum
Eriophorum russeolum

Eriophorum section Phyllanthela:

Eriophorum angustifolium
Eriophorum latifolium
Eriophorum gracile

In 1905, the American botanist Merritt Lyndon Fernald placed the North American species of Eriophorum into Andersson's sections as follows:
Eriophorum section Vaginata:

Eriophorum scheuchzeri
Eriophorum chamissonis
Eriophorum vaginatum
Eriophorum callitrix
Eriophorum opacum ''n. comb.

Eriophorum section Phyllanthela:

Eriophorum gracile
Eriophorum tenellum
Eriophorum polystachion
Eriophorum viridicarinatum n. comb.
Eriophorum virginicum''