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divergent buckwheat, divergent wild buckwheat

woolly-cup wild buckwheat, woollycup buckwheat

Habit Herbs, spreading, 1–2(–3) dm, puberulent to short-pilose, greenish to reddish. Herbs, erect or matted, sometimes scapose, 1–3.5 × 1–2 dm or 0.05–0.2 × 0.5–3.5 dm, floccose or silky-tomentose, grayish.
Stems

aerial flowering stems decumbent to spreading, 0.3–0.5 dm, puberulent to short-pilose.

spreading or matted, occasionally with persistent leaf bases, up to 1/4 or more height of plant;

caudex stems matted;

aerial flowering stems erect or nearly so, slender, solid, not fistulose, 1–2 dm and floccose, or (0.1–)0.02–0.5(–0.65) dm and silky-tomentose.

Leaves

basal and cauline;

basal: petiole 1–4(–5) cm, puberulent to short-pilose, blade elliptic-oblong to orbiculate, 1–2(–2.5) × 1–2(–2.5) cm, puberulent to short-pilose and green on both surfaces;

cauline: petiole (0–)0.1–2 cm, puberulent to short-pilose, absent distally, blades opposite, oblanceolate to oblong or elliptic, 0.3–1(–1.5) × 0.2–0.8(–1.2) cm, similar to basal blade.

basal, 1 per node or fasciculate in terminal tufts;

petiole 0.1–2.5(–3) cm, tomentose to floccose;

blade lanceolate or oblanceolate to narrowly elliptic, 1–2.5(–3) × 0.3–0.5(–0.8) cm, or 0.4–1.2 × 0.1–0.3(–0.35) cm, densely white- or silvery-tomentose on both surfaces, margins plane.

Inflorescences

cymose, distally uniparous due to suppression of secondary branches, diffuse, 5–25 × 10–45 cm;

branches puberulent;

bracts 1–3(–5) × 1–2 mm.

capitate, subcapitate, umbellate-cymose, or cymose, 2–20 × 2–20 cm, floccose or, if matted, 0.3–1 × 0.3–1 cm;

branches open and divided 1–3 times, 2–20 cm, floccose or if matted, (0–)0.3–0.85 cm, silky-tomentose;

bracts 3, scalelike, triangular, (0.5–)1–3 mm.

Peduncles

absent.

absent or erect, slender, 2–15 mm, floccose.

Involucres

somewhat appressed to branches, campanulate, 1–2 × 1–2 mm, pilose;

teeth 5, lobelike, spreading to somewhat reflexed, 0.7–1.5 mm.

1 per node or 2–5 per cluster, broadly campanulate, 1.5–4 × (2–)3–6(–8) mm, tomentose;

teeth 5, erect to spreading, 1–1.5 mm.

Flowers

(1–)1.5–2 mm;

perianth yellow, rarely pale yellow, hispidulous and glandular with yellowish-white hairs;

tepals monomorphic, oblong-lanceolate to oblong-ovate;

stamens included, 0.7–1.5 mm;

filaments pilose proximally.

2.5–5(–6) mm;

perianth yellow, densely white-pubescent;

tepals connate proximal 1/3, monomorphic, lanceolate to broadly lanceolate;

stamens exserted, 3.5–5 mm;

filaments glabrous.

Achenes

light brown, 3-gonous, 1.5–2 mm.

brown to dark brown, 3–4 mm, villous to tomentose.

Eriogonum divaricatum

Eriogonum lachnogynum

Phenology Flowering May–Oct.
Habitat Heavy clay flats and slopes, saltbush, greasewood, and sagebrush communities, pinyon-juniper woodlands
Elevation 1100-2300(-2500) m (3600-7500(-8200) ft)
Distribution
from FNA
AZ; CO; NM; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; KS; NM; OK; TX
[WildflowerSearch map]
[BONAP county map]
Discussion

Eriogonum divaricatum basically is a species of the Colorado Plateau of southwestern Wyoming (Sublette, Sweetwater, and Uinta counties), eastern Utah (Carbon, Emery, Garfield, Grand, Kane, San Juan, Sevier, and Wayne counties), western Colorado (Mesa and Montezuma counties), northern Arizona (Apache, Coconino, and Navajo counties), and northwestern New Mexico (McKinley and San Juan counties), where it is infrequent to common but only rarely abundant. There are several disjunct populations well removed from that core area; the species occurs in Beaver and Millard counties of west-central Utah, and in Clayhole Valley, Mohave County, Arizona. In New Mexico, it was found around San Ysidro, Sandoval County, in 1926. The most extreme disjunctions were two populations found in Argentina during the growing season of 1899–1900. Those plants were named Eriogonum ameghinoi Spegazzini, which ultimately became the only species of the genus Sanmartinia M. Buchinger. Probably introduced there by migrating birds, the species did not persist in South America (J. L. Reveal 1981b).

The divergent wild buckwheat was used ceremonially by the Navajo (Diné) people in one of their snake dances, and portions of the plant were smoked in the treatment of snakebite (A. Clifford, pers. comm.; L. C. Wyman and S. K. Harris 1951).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 3 (3 in the flora).

The Navajo or Diné people consider Eriogonum lachnogynum to be a “life medicine,” making a concoction of shredded roots for the treatment of internal, and some external, ailments. It is often given for diarrhea.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Plants erect; inflorescences subcapitate, umbellate-cymose, or cymose; flowering stems 1-2 dm at full anthesis; leaf blades 1-2.5(-3) × 0.3-0.5(-0.8) cm; widespread, not in Arizona
var. lachnogynum
1. Plants cespitose mats; inflorescences capitate; flowering stems 0.01-0.65 dm at full anthesis; leaf blades 0.4-1.2 × 0.1-0.35 cm; Arizona, New Mexico
→ 2
2. Flowering stems 0.1-0.5(-0.65) dm, longer than leaves
var. sarahiae
2. Flowering stems (0.01-)0.02-0.05(-0.12) dm, shorter than or just exceeding leaves
var. colobum
Source FNA vol. 5, p. 429. FNA vol. 5, p. 286.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oregonium Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla
Sibling taxa
E. abertianum, E. acaule, E. alatum, E. aliquantum, E. allenii, E. alpinum, E. ammophilum, E. ampullaceum, E. androsaceum, E. anemophilum, E. angulosum, E. annuum, E. apiculatum, E. apricum, E. arborescens, E. arcuatum, E. aretioides, E. argillosum, E. argophyllum, E. arizonicum, E. artificis, E. atrorubens, E. baileyi, E. batemanii, E. bicolor, E. bifurcatum, E. brachyanthum, E. brachypodum, E. brandegeei, E. breedlovei, E. brevicaule, E. butterworthianum, E. caespitosum, E. capillare, E. cernuum, E. chrysops, E. cinereum, E. cithariforme, E. clavatum, E. clavellatum, E. codium, E. collinum, E. coloradense, E. compositum, E. concinnum, E. congdonii, E. contiguum, E. contortum, E. correllii, E. corymbosum, E. covilleanum, E. crocatum, E. cronquistii, E. crosbyae, E. cusickii, E. darrovii, E. dasyanthemum, E. davidsonii, E. deflexum, E. deserticola, E. desertorum, E. diatomaceum, E. diclinum, E. douglasii, E. eastwoodianum, E. effusum, E. elatum, E. elegans, E. elongatum, E. ephedroides, E. eremicola, E. eremicum, E. ericifolium, E. esmeraldense, E. evanidum, E. exaltatum, E. exilifolium, E. fasciculatum, E. flavum, E. fusiforme, E. giganteum, E. gilmanii, E. glandulosum, E. gordonii, E. gossypinum, E. gracile, E. gracilipes, E. gracillimum, E. grande, E. greggii, E. gypsophilum, E. havardii, E. heermannii, E. helichrysoides, E. hemipterum, E. heracleoides, E. hieracifolium, E. hirtellum, E. hirtiflorum, E. hoffmannii, E. holmgrenii, E. hookeri, E. howellianum, E. hylophilum, E. incanum, E. inerme, E. inflatum, E. intrafractum, E. jamesii, E. jonesii, E. kelloggii, E. kennedyi, E. kingii, E. lachnogynum, E. lancifolium, E. latens, E. latifolium, E. lemmonii, E. leptocladon, E. leptophyllum, E. libertini, E. lobbii, E. loganum, E. lonchophyllum, E. longifolium, E. luteolum, E. maculatum, E. mancum, E. marifolium, E. mensicola, E. microthecum, E. mitophyllum, E. mohavense, E. molestum, E. mortonianum, E. multiflorum, E. natum, E. nealleyi, E. nervulosum, E. nidularium, E. niveum, E. nortonii, E. novonudum, E. nudum, E. nummulare, E. nutans, E. ochrocephalum, E. ordii, E. ostlundii, E. ovalifolium, E. palmerianum, E. panamintense, E. panguicense, E. parishii, E. parvifolium, E. pauciflorum, E. pelinophilum, E. pendulum, E. pharnaceoides, E. plumatella, E. polycladon, E. polypodum, E. prattenianum, E. prociduum, E. pulchrum, E. pusillum, E. pyrolifolium, E. racemosum, E. reniforme, E. ripleyi, E. rixfordii, E. robustum, E. rosense, E. roseum, E. rotundifolium, E. rubricaule, E. rupinum, E. salicornioides, E. saxatile, E. scabrellum, E. scopulorum, E. shockleyi, E. siskiyouense, E. smithii, E. soliceps, E. soredium, E. spathulatum, E. spectabile, E. spergulinum, E. sphaerocephalum, E. strictum, E. subreniforme, E. suffruticosum, E. temblorense, E. tenellum, E. ternatum, E. terrenatum, E. thomasii, E. thompsoniae, E. thornei, E. thurberi, E. thymoides, E. tiehmii, E. tomentosum, E. trichopes, E. tripodum, E. truncatum, E. tumulosum, E. twisselmannii, E. umbellatum, E. ursinum, E. vestitum, E. villiflorum, E. vimineum, E. viridescens, E. viridulum, E. viscidulum, E. visheri, E. watsonii, E. wetherillii, E. wootonii, E. wrightii, E. zionis
E. abertianum, E. acaule, E. alatum, E. aliquantum, E. allenii, E. alpinum, E. ammophilum, E. ampullaceum, E. androsaceum, E. anemophilum, E. angulosum, E. annuum, E. apiculatum, E. apricum, E. arborescens, E. arcuatum, E. aretioides, E. argillosum, E. argophyllum, E. arizonicum, E. artificis, E. atrorubens, E. baileyi, E. batemanii, E. bicolor, E. bifurcatum, E. brachyanthum, E. brachypodum, E. brandegeei, E. breedlovei, E. brevicaule, E. butterworthianum, E. caespitosum, E. capillare, E. cernuum, E. chrysops, E. cinereum, E. cithariforme, E. clavatum, E. clavellatum, E. codium, E. collinum, E. coloradense, E. compositum, E. concinnum, E. congdonii, E. contiguum, E. contortum, E. correllii, E. corymbosum, E. covilleanum, E. crocatum, E. cronquistii, E. crosbyae, E. cusickii, E. darrovii, E. dasyanthemum, E. davidsonii, E. deflexum, E. deserticola, E. desertorum, E. diatomaceum, E. diclinum, E. divaricatum, E. douglasii, E. eastwoodianum, E. effusum, E. elatum, E. elegans, E. elongatum, E. ephedroides, E. eremicola, E. eremicum, E. ericifolium, E. esmeraldense, E. evanidum, E. exaltatum, E. exilifolium, E. fasciculatum, E. flavum, E. fusiforme, E. giganteum, E. gilmanii, E. glandulosum, E. gordonii, E. gossypinum, E. gracile, E. gracilipes, E. gracillimum, E. grande, E. greggii, E. gypsophilum, E. havardii, E. heermannii, E. helichrysoides, E. hemipterum, E. heracleoides, E. hieracifolium, E. hirtellum, E. hirtiflorum, E. hoffmannii, E. holmgrenii, E. hookeri, E. howellianum, E. hylophilum, E. incanum, E. inerme, E. inflatum, E. intrafractum, E. jamesii, E. jonesii, E. kelloggii, E. kennedyi, E. kingii, E. lancifolium, E. latens, E. latifolium, E. lemmonii, E. leptocladon, E. leptophyllum, E. libertini, E. lobbii, E. loganum, E. lonchophyllum, E. longifolium, E. luteolum, E. maculatum, E. mancum, E. marifolium, E. mensicola, E. microthecum, E. mitophyllum, E. mohavense, E. molestum, E. mortonianum, E. multiflorum, E. natum, E. nealleyi, E. nervulosum, E. nidularium, E. niveum, E. nortonii, E. novonudum, E. nudum, E. nummulare, E. nutans, E. ochrocephalum, E. ordii, E. ostlundii, E. ovalifolium, E. palmerianum, E. panamintense, E. panguicense, E. parishii, E. parvifolium, E. pauciflorum, E. pelinophilum, E. pendulum, E. pharnaceoides, E. plumatella, E. polycladon, E. polypodum, E. prattenianum, E. prociduum, E. pulchrum, E. pusillum, E. pyrolifolium, E. racemosum, E. reniforme, E. ripleyi, E. rixfordii, E. robustum, E. rosense, E. roseum, E. rotundifolium, E. rubricaule, E. rupinum, E. salicornioides, E. saxatile, E. scabrellum, E. scopulorum, E. shockleyi, E. siskiyouense, E. smithii, E. soliceps, E. soredium, E. spathulatum, E. spectabile, E. spergulinum, E. sphaerocephalum, E. strictum, E. subreniforme, E. suffruticosum, E. temblorense, E. tenellum, E. ternatum, E. terrenatum, E. thomasii, E. thompsoniae, E. thornei, E. thurberi, E. thymoides, E. tiehmii, E. tomentosum, E. trichopes, E. tripodum, E. truncatum, E. tumulosum, E. twisselmannii, E. umbellatum, E. ursinum, E. vestitum, E. villiflorum, E. vimineum, E. viridescens, E. viridulum, E. viscidulum, E. visheri, E. watsonii, E. wetherillii, E. wootonii, E. wrightii, E. zionis
Subordinate taxa
E. lachnogynum var. colobum, E. lachnogynum var. lachnogynum, E. lachnogynum var. sarahiae
Name authority Hooker: Hooker’s J. Bot. Kew Gard. Misc. 5: 265. (1853) Torrey ex Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 8. (1856)
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