The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

unarmed buckwheat, unarmed wild buckwheat

divergent buckwheat, divergent wild buckwheat

Habit Herbs, spreading, annual, 0.5–3 dm, glandular, greenish or reddish. Herbs, spreading, 1–2(–3) dm, puberulent to short-pilose, greenish to reddish.
Stems

caudex absent;

aerial flowering stems mostly erect, solid, not fistulose, 0.1–0.5 dm, glandular.

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

Leaves

basal and cauline;

basal: petiole 0.5–2 cm, glabrous, not or indistinctly winged, ciliate, blade spatulate, 1–4(–4.5) × 0.4–1.5(–1.8) cm, glabrous, margins ciliate;

cauline sessile, blade lanceolate, 0.3–1 × 0.1–0.3 cm, similar to basal blade.

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.

Inflorescences

cymose, open or diffuse, 5–25 × 5–30 cm;

branches glandular;

bracts 3, scalelike, 0.5–1.5 × 1–2 mm, occasionally semileaflike, 4–10(–12) × 1–5 mm.

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

branches puberulent;

bracts 1–3(–5) × 1–2 mm.

Peduncles

absent or erect, straight, slender, 0.1–1 cm, glandular.

absent.

Involucres

turbinate, 1.5–1.9 × 1–1.2 mm, glabrous or hispidulous;

teeth 4, erect or nearly so, 0.8–1.2 mm.

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

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

Flowers

4–6, 1.2–1.8 mm;

perianth pink to reddish, hirsutulous with stiff, white, hooked hairs;

tepals monomorphic, oblong;

stamens included, 1–1.5 mm;

filaments glabrous.

(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.

Achenes

brown, lenticular, 1.5–1.9 mm, glabrous;

beak not exserted beyond tepals.

light brown, 3-gonous, 1.5–2 mm.

Eriogonum inerme

Eriogonum divaricatum

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
CA; ID
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; NM; UT; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

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

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.)

Key
1. Involucres glabrous; Coast and Transverse ranges, California, disjunct in Boise County, Idaho
var. inerme
1. Involucres hispidulous; Transverse Ranges and s Sierra Nevada, disjunct in Tuolumne County, California
var. hispidulum
Source FNA vol. 5, p. 410. FNA vol. 5, p. 429.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oregonium
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. 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. 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. 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
Subordinate taxa
E. inerme var. hispidulum, E. inerme var. inerme
Synonyms Oxytheca inermis
Name authority (S. Watson) Jepson: Fl. Calif. 1: 406. (1914) Hooker: Hooker’s J. Bot. Kew Gard. Misc. 5: 265. (1853)
Web links