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unarmed buckwheat, unarmed wild buckwheat

Gordon's buckwheat, Gordon's eriogonum, Gordon's wild buckwheat

Habit Herbs, spreading, annual, 0.5–3 dm, glandular, greenish or reddish. Herbs, erect to spreading, annual, (0.5–)1–5(–7) dm, glabrous or sparsely hispid, grayish.
Stems

caudex absent;

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

caudex absent;

aerial flowering stems erect, solid, not fistulose, 0.5–1.5(–3) dm, glabrous or sparsely hispid.

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;

petiole 1–5 cm, glabrous or sparsely hirsute;

blade obovate to round or reniform, 1–5 × 1–5 cm, sparsely villous to hirsute and green on both surfaces, becoming glabrous with age, margins plane.

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, open to dense, 5–40(–50) × 5–50 cm;

branches not fistulose, glabrous or sparsely hispid;

bracts 3, scalelike, 0.5–2(–3) × 0.5–2.5 mm.

Peduncles

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

erect, straight, slender, 0.5–2.5(–4) cm, glabrous.

Involucres

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

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

campanulate, 0.6–1.5 × 0.8–1.5 mm, glabrous;

teeth 5, erect, 0.2–0.4 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.

1–2.5 mm;

perianth white with greenish or reddish midribs, rarely yellowish, becoming pink to rose, glabrous;

tepals monomorphic, oblong to narrowly ovate;

stamens included to exserted, 1–1.8 mm;

filaments glabrous.

Achenes

brown, lenticular, 1.5–1.9 mm, glabrous;

beak not exserted beyond tepals.

shiny light brown to brown, 3-gonous, 2–2.5 mm, glabrous.

Eriogonum inerme

Eriogonum gordonii

Phenology Flowering May–Oct.
Habitat Sandy to clayey flats and slopes, saltbush, greasewood, and sagebrush communities, pinyon and/or juniper or montane conifer woodlands
Elevation 900-2200 m (3000-7200 ft)
Distribution
from FNA
CA; ID
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; NE; NM; SD; 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 gordonii is common to even locally abundant throughout a range that extends in an arc from the Colorado Plateau of extreme northern Coconino and Apache counties, Arizona, and San Juan County, New Mexico, northward through the desert regions of eastern Utah and western Colorado into southwestern Wyoming, then northeastward mainly in short-grass prairie through east-central Wyoming and extreme northwestern Nebraska to South Dakota. A series of disjunct populations occurs in Fremont and Las Animas counties in Colorado. The species can be weedy in appearance but usually is absent from areas of significant disturbance, unlike other annual wild buckwheats.

(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. 391.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma
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. 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. 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) Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 20. (1856)
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