''Eriogonum'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of flowering plants in the family

Polygonaceae The Polygonaceae are a family of flowering plants known informally as the knotweed family or smartweed—buckwheat family in the United States. The name is based on the genus '' Polygonum'', and was first used by Antoine Laurent de Jussieu in 1 ...

. The genus is found in North America and is known as wild buckwheat. This is a highly species-rich genus, and indications are that active speciation is continuing. It includes some common wildflowers such as the

California buckwheat ''Eriogonum fasciculatum'' is a species of wild buckwheat known by the common names California buckwheat and flat-topped buckwheat. Characterized by small, white and pink flower clusters that give off a cottony effect, this species grows vari ...

(''Eriogonum fasciculatum''). The genus derived its name from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

word ''erion'' meaning 'wool' and ''gonu'' meaning 'knee or joint'. The author of the genus, Michaux, explained the name as describing the first named species of the genus (''E. tomentosum'') as a wooly plant with sharply bent stems (''"planta lanata, geniculata"''). Despite sharing the common name "buckwheat", ''Eriogonum'' is part of a different genus than the cultivated European

buckwheat Buckwheat (''Fagopyrum esculentum''), or common buckwheat, is a flowering plant in the knotweed family Polygonaceae cultivated for its grain-like seeds and as a cover crop. The name "buckwheat" is used for several other species, such as ''Fagopy ...

and than other plant species also called wild buckwheat. It came into the news in 2005 when the

Mount Diablo buckwheat ''Eriogonum truncatum'', the Mount Diablo buckwheat, is a small pink wildflower, believed to have been extinct since 1936 until its rediscovery in 2005. The species is only known to live on Mount Diablo in Contra Costa County, northern Califor ...

(''Eriogonum truncatum'', believed to be extinct) was rediscovered.

Ecology

''Eriogonum'' species are used as food plants by the

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. ...

e of some Lepidoptera (butterflies and moths). An example of a butterfly that uses this plant for food is the ''

Lycaena heteronea The blue copper, also known as ''Lycaena heteronea'', is an American butterfly that belongs to the gossamer-winged family. The butterfly is named so because of the bright blue hue of the upper side of the males' wings. Females are brown on thei ...

''. Several of these are

monophagous A generalist species is able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources (for example, a heterotroph with a varied diet). A specialist species can thrive only in a narrow range of e ...

, meaning their caterpillars only feed on this genus, sometimes just on a single

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

of ''Eriogonum''. Wild buckwheat flowers are also an important source of food for these and other Lepidoptera. In some cases, the relationship is so close that ''Eriogonum'' and dependent Lepidoptera are in danger of

coextinction Coextinction and cothreatened refer to the phenomena of the loss or decline of a host species resulting in the loss or endangerment of an other species that depends on it, potentially leading to cascading effects across trophic levels. The term or ...

. Monophagous Lepidoptera on wild buckwheat include: * ''

Apodemia mormo ''Apodemia mormo'' (Mormon metalmark) is a principally Nearctic butterfly in the family Riodinidae. It is a particularly fascinating species for ecological and evolutionary research, as evidenced by its shifting taxonomic classifications. Confl ...

'' (Mormon metalmark) – feeds exclusively on ''Eriogonum'' ** ''

Apodemia mormo langei ''Apodemia mormo langei'', the Lange's metalmark butterfly, is an endangered North American butterfly. It is a subspecies of the Mormon metalmark and belongs to the family Riodinidae. The butterfly is endemic to California, where it is known fr ...

'' (Lange's metalmark) – only known from ''Eriogonum nudum'' ssp. ''auriculatum'' * ''

Chionodes dammersi ''Chionodes dammersi'' is a moth in the family Gelechiidae. It is found in North America, where it has been recorded from California and Arizona. The larvae feed on '' Eriogonum elongatum'', '' Eriogonum inflatum'', '' Eriogonum abrorescens'', ...

'' – feeds exclusively on ''Eriogonum'' * '' Chionodes luteogeminatus'' – only known from ''Eriogonum niveum'' * ''Euphilotes enoptes smithi'' ( Smith's blue butterfly) – only known from ''Eriogonum latifolium'' and ''Eriogonum parvifolium'' * ''Euphilotes battoides allyni'' (

El Segundo blue butterfly The El Segundo blue (''Euphilotes battoides allyni'') is a rare subspecies of the square-spotted blue butterfly. It is endemic to a small dune ecosystem in Southern California that used to be a community called Palisades del Rey, close to the ...

) - only known from ''Eriogonum parvifolium'' Additionally, bees of the

sagebrush steppe Sagebrush steppe is a type of shrub-steppe, a plant community characterized by the presence of shrubs, and usually dominated by sagebrush, any of several species in the genus '' Artemisia''.California buckwheat ''Eriogonum fasciculatum'' is a species of wild buckwheat known by the common names California buckwheat and flat-topped buckwheat. Characterized by small, white and pink flower clusters that give off a cottony effect, this species grows vari ...

were and still are used as medicinal and food crops by Native American tribes.

Selected species

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''Eriogonum ursinum">Talus buckwheat
''Eriogonum ursinum'' image:Eriogonum wrightii var subscaposum 1.jpg">thumb">right">''Eriogonum wrightii'' var. ''subscaposum'' * ''Eriogonum abertianum'' – Abert's buckwheat * ''Eriogonum alatum'' – winged buckwheat * ''Eriogonum alexanderae''Grady, B. R. and J. L. Reveal. (2011)
New combinations and a new species of ''Eriogonum'' (Polygonaceae: Eriogonoideae) from the Great Basin Desert, United States.
''Phytotaxa'' 24 33–38. * '' Eriogonum aliquantum'' – Cimarron buckwheat * '' Eriogonum alpinum'' – trinity buckwheat * '' Eriogonum ampullaceum'' – mono buckwheat * '' Eriogonum androsaceum'' – rock-jasmine buckwheat * '' Eriogonum angulosum'' – anglestem buckwheat * '' Eriogonum apiculatum'' – San Jacinto buckwheat * '' Eriogonum apricum'' – Ione buckwheat * '' Eriogonum arborescens'' – Santa Cruz Island buckwheat * '' Eriogonum argillosum'' – clay buckwheat * '' Eriogonum argophyllum'' – Sulphur Hot Springs buckwheat, Ruby Valley buckwheat * '' Eriogonum baileyi'' – Bailey's buckwheat * '' Eriogonum brachyanthum'' – shortflower buckwheat * '' Eriogonum brachypodum'' – Parry's buckwheat * '' Eriogonum brandegeei'' – Brandegee's buckwheat * '' Eriogonum breedlovei'' – Paiute buckwheat * '' Eriogonum brevicaule'' – shortstem buckwheat * '' Eriogonum butterworthianum'' – Butterworth's buckwheat * '' Eriogonum caespitosum'' – matted buckwheat * '' Eriogonum calcareum'' * '' Eriogonum callistum'' – Tehachapi buckwheat * '' Eriogonum cedrorum'' – The Cedars buckwheat * '' Eriogonum cernuum'' – nodding buckwheat * ''

Eriogonum cinereum ''Eriogonum cinereum'' is a species of wild buckwheat known by the common names coastal buckwheat and ashyleaf buckwheat. Distribution This shrub is endemic to the coastline of Southern California, primarily within Los Angeles County and Vent ...

'' – ashyleaf buckwheat, coastal buckwheat * '' Eriogonum cithariforme'' – Cithara buckwheat * '' Eriogonum codium'' – basalt desert buckwheat * '' Eriogonum coloradense'' – Colorado buckwheat * ''

Eriogonum compositum ''Eriogonum'' is a genus of flowering plants in the family Polygonaceae. The genus is found in North America and is known as wild buckwheat. This is a highly species-rich genus, and indications are that active speciation is continuing. It incl ...

'' – arrowleaf buckwheat * '' Eriogonum congdonii'' – Congdon's buckwheat * '' Eriogonum contiguum'' – Reveal's buckwheat * '' Eriogonum corymbosum'' – crispleaf buckwheat ** '' Eriogonum corymbosum var. nilesii'' – Nile's wild buckwheat, Las Vegas buckwheat * '' Eriogonum covilleanum'' – Coville's buckwheat * '' Eriogonum crocatum'' – conejo buckwheat or saffron buckwheat * '' Eriogonum crosbyae'' – Crosby's buckwheat * ''

Eriogonum cusickii ''Eriogonum'' is a genus of flowering plants in the family Polygonaceae. The genus is found in North America and is known as wild buckwheat. This is a highly species-rich genus, and indications are that active speciation is continuing. It in ...

'' – Cusick's buckwheat * '' Eriogonum dasyanthemum'' – chaparral buckwheat * '' Eriogonum davidsonii'' – Davidson's buckwheat * ''

Eriogonum deflexum ''Eriogonum deflexum'' is a species of wild buckwheat known by the common names flatcrown buckwheat, flat-top buckwheat, and skeletonweed. This plant is native to the southwestern United States and northwestern Mexico, where it is common and gr ...

'' – flatcrown buckwheat * '' Eriogonum deserticola'' – Colorado Desert buckwheat * '' Eriogonum diatomaceum'' – Churchill Narrows buckwheat * '' Eriogonum diclinum'' – Jaynes Canyon buckwheat * '' Eriogonum domitum'' * ''

Eriogonum douglasii ''Eriogonum douglasii'' is a species of Eriogonum, wild buckwheat known by the common name Douglas' buckwheat. It is native to the western United States, including the Pacific Northwest and part of the Great Basin. Description ''Eriogonum dougla ...

'' – Douglas buckwheat * '' Eriogonum elatum'' – tall woolly buckwheat * '' Eriogonum encelioides'' – Encelia buckwheat * ''

Eriogonum eremicola ''Eriogonum eremicola'' is a rare species of wild buckwheat known by the common names Telescope Peak buckwheat and Wild Rose Canyon buckwheat. It is endemic to Inyo County, California, where it is known from only a few occurrences in the Inyo Mo ...

'' – Telescope Peak buckwheat * ''

Eriogonum evanidum ''Eriogonum evanidum'' is a rare species of wild buckwheat known by the common name vanishing wild buckwheat. It is native to southern California and Baja California, where it has been collected from widely scattered areas. Most historical occur ...

'' – vanishing wild buckwheat * '' Eriogonum exilifolium'' – dropleaf buckwheat * ''

Eriogonum fasciculatum ''Eriogonum fasciculatum'' is a species of wild buckwheat known by the common names California buckwheat and flat-topped buckwheat. Characterized by small, white and pink flower clusters that give off a cottony effect, this species grows vari ...

'' – California buckwheat * ''

Eriogonum flavum ''Eriogonum flavum'' is a species of wild buckwheat. Common names This flower has several common names, including but not limited to: Pipers buckwheat, Pipers golden buckwheat, Yellow umbrella plant,Neil L. Jennings and Pipers Wild Buckwheat ...

'' – yellow buckwheat * ''

Eriogonum giganteum ''Eriogonum giganteum'', with the common name St. Catherine's lace, is a species of Eriogonum, wild buckwheat in Southern California.Eriogonum gilmanii'' – Gilman's buckwheat Eriogonum thymoides 9256

* '' Eriogonum gossypinum'' – cottony buckwheat * '' Eriogonum gracile'' – slender woolly buckwheat * '' Eriogonum gracilipes'' – White Mountain buckwheat, raspberry buckwheat * '' Eriogonum gracillimum'' – rose and white buckwheat * ''

Eriogonum grande ''Eriogonum grande'' is a species of wild buckwheat known by the common name redflower buckwheat. It is native to northwestern Baja California, as well as the Channel Islands of California. It is a mat-forming perennial herb producing tall, stou ...

'' – redflower buckwheat * '' Eriogonum gypsophilum'' – gypsum wild buckwheat * '' Eriogonum heermannii'' – Heermann's buckwheat * '' Eriogonum helichrysoides'' – Strawflower wild buckwheat * ''

Eriogonum heracleoides ''Eriogonum heracleoides'' (common names; parsnipflower buckwheat, whorled buckwheat, and Wyeth buckwheat) is a plant of western North America that has many flowering clusters which are usually cream colored, or off-white. It can usually be found ...

'' – parsnip-flower Buckwheat * '' Eriogonum hirtellum'' – Klamath Mountain Buckwheat * '' Eriogonum hoffmannii'' – Hoffmann's buckwheat * '' Eriogonum hookeri'' – Hooker's buckwheat * '' Eriogonum incanum'' – frosted buckwheat * '' Eriogonum inflatum'' – desert trumpet, bladderstem, Indian pipe-weed * '' Eriogonum intrafractum'' – napkinring, jointed buckwheat * '' Eriogonum jamesii'' – James' buckwheat * '' Eriogonum kelloggii'' – red mountain buckwheat Eriogonum nidularium 5

* '' Eriogonum kennedyi'' – Kennedy's buckwheat * '' Eriogonum latens'' – Inyo buckwheat * ''

Eriogonum latifolium ''Eriogonum latifolium'' is a species of wild buckwheat known by the common names seaside buckwheat and coast buckwheat. This plant is native to the coastline of the western United States from Washington to central California California ...

'' – seaside buckwheat * '' Eriogonum libertini'' – Dubakella Mountain buckwheat * '' Eriogonum lobbii'' – Lobb's buckwheat * '' Eriogonum longifolium'' – longleaf buckwheat ** '' Eriogonum longifolium var. harperi'' – Harper's umbrella plant or Harper's buckwheat ** '' Eriogonum longifolium var. gnaphalifolium'' – scrub buckwheat or long-leaf wild Buckwheat ** '' Eriogonum longifolium'' var. ''longifolium'' – longleaf buckwheat ** '' Eriogonum longifolium var. lindheimeri'' – Lindheimer's long-leaf ''Eriogonum'' or Lindheimer's buckwheat Eriogonum inflatum 4

* '' Eriogonum luteolum'' – goldencarpet buckwheat * '' Eriogonum maculatum'' – spotted buckwheat * '' Eriogonum marifolium'' – marumleaf buckwheat * '' Eriogonum microthecum'' – slender buckwheat * '' Eriogonum mohavense'' – Western Mojave buckwheat * '' Eriogonum molestum'' – pineland buckwheat * '' Eriogonum nervulosum'' – Snow Mountain buckwheat * ''

Eriogonum nidularium ''Eriogonum nidularium'' is a species of wild buckwheat known by the common name birdnest buckwheat. It is native to the sandy flats and desert dry washes of the Mojave Desert and Great Basin in the western United States, where it is common and ...

'' – birdnest buckwheat * '' Eriogonum niveum'' – snow buckwheat * '' Eriogonum nortonii'' – pinnacles buckwheat * ''

Eriogonum nudum ''Eriogonum nudum'' is a perennial shrub of the wild buckwheat genus which is known by the common name naked buckwheat or nude buckwheat. Description The ''Eriogonum nudum'' plant is a tall, bare, leafless stem, bifurcating into more stems, ...

'' – naked buckwheat ** ''Eriogonum nudum'' ssp. ''auriculatum'' Eriogonum heermannii var sulcatum 11

* '' Eriogonum nummulare'' – Kearney buckwheat, money buckwheat * '' Eriogonum ochrocephalum'' – whitewoolly buckwheat * ''

Eriogonum ovalifolium ''Eriogonum ovalifolium'' is a species of wild buckwheat known by the common name cushion buckwheat. It is native to western North America from California to Alberta, where it is a member of many plant communities in varied habitats, including t ...

'' – cushion buckwheat, oval-leaf buckwheat * '' Eriogonum palmerianum'' – Palmer's buckwheat * '' Eriogonum panamintense'' – Panamint Mountain buckwheat * '' Eriogonum parishii'' – mountainmist * ''

Eriogonum parvifolium ''Eriogonum parvifolium'' is a species in the family Polygonaceae that occurs on dune formations in the coastal area of Central and Southern California. This evergreen shrub grows to a height of 30 to 100 centimeters with a spread of approxi ...

'' – coast buckwheat, dune buckwheat or cliff buckwheat * '' Eriogonum pauciflorum'' – Fewflower buckwheat * '' Eriogonum pelinophilum'' – clay-loving wild buckwheat * '' Eriogonum pendulum'' – waldo buckwheat * '' Eriogonum plumatella'' – yucca buckwheat * '' Eriogonum prattenianum'' – Nevada City buckwheat * '' Eriogonum prociduum'' – prostrate buckwheat Eriogonum crocatum

* '' Eriogonum pusillum'' – yellowturbans * '' Eriogonum pyrolifolium'' – pyrola-leaved buckwheat * '' Eriogonum reniforme'' – kidneyleaf buckwheat * '' Eriogonum rixfordii'' – pagoda buckwheat * '' Eriogonum rosense'' – rosy buckwheat, mountain rose buckwheat ** '' Eriogonum rosense var. beatleyae'' – Beatley's buckwheat * '' Eriogonum roseum'' – wand buckwheat * '' Eriogonum salicornioides'' – glasswort buckwheat * '' Eriogonum saxatile'' – hoary buckwheat * '' Eriogonum shockleyi'' – cowpie buckwheat Eriogonumbaileyi

* '' Eriogonum siskiyouense'' – Siskiyou buckwheat * '' Eriogonum soredium'' – Frisco buckwheat * '' Eriogonum spectabile'' – Barron's buckwheat * ''

Eriogonum spergulinum ''Eriogonum spergulinum'' is a species of wild buckwheat known by the common name spurry buckwheat. Varieties There are three varieties: two are limited and endemic to the Sierra Nevada in California; while the more common of the three, var. '' ...

'' – spurry buckwheat * ''

Eriogonum sphaerocephalum ''Eriogonum sphaerocephalum'' is a species of wild buckwheat known by the common names rock buckwheat and round-headed desert buckwheat. It is native to the western United States. Habitat ''Eriogonum sphaerocephalum'' can be found primarily e ...

'' – rock buckwheat * '' Eriogonum strictum'' – blue mountain buckwheat * '' Eriogonum ternatum'' – ternate buckwheat * '' Eriogonum tiehmii'' – Tiehm's buckwheat * '' Eriogonum thomasii'' – Thomas' buckwheat * '' Eriogonum thurberi'' – Thurber's buckwheat * '' Eriogonum thymoides'' – thymeleaf buckwheat * '' Eriogonum tomentosum'' – dogtongue wild buckwheat * '' Eriogonum trichopes'' – little desert trumpet Eriogonumspergulinum

* '' Eriogonum tripodum'' – tripod buckwheat * '' Eriogonum truncatum'' – Mount Diablo buckwheat * '' Eriogonum umbellatum'' – sulphurflower buckwheat * ''

Eriogonum ursinum ''Eriogonum ursinum'' is a species of wild buckwheat known by the common names Bear Valley buckwheat and talus buckwheat. It is endemic to northern California where it is found on mountains from the northern Sierra Nevada to the southern Klama ...

'' – talus buckwheat, Bear Valley buckwheat * ''

Eriogonum vimineum ''Eriogonum vimineum'' is a species of wild buckwheat known by the common name wickerstem buckwheat. It is native to the Northwestern United States, California, and Nevada where it is common to abundant in many types of habitat, including the S ...

'' – wickerstem buckwheat * '' Eriogonum viridescens'' – twotooth buckwheat * '' Eriogonum visheri'' – Dakota wild buckwheat, Visher's buckwheat * '' Eriogonum wrightii'' – bastardsage * '' Eriogonum zapatoense'' * '' Eriogonum zionis'' – Zion buckwheat

References

External links

Genus treatment in the ''Jepson Manual''

Mt. Diablo buckwheat rediscovered
{{Taxonbar, from=Q2707277 Polygonaceae genera