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unarmed buckwheat, unarmed wild buckwheat

altered andesite wild buckwheat, granite buckwheat

Habit Herbs, spreading, annual, 0.5–3 dm, glandular, greenish or reddish. Herbs, erect, matted, 0.5–3 × 1–2 dm, tomentose to floccose.
Stems

caudex absent;

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

caudex absent;

aerial flowering stems erect or nearly so, stout, solid, not fistulose, usually arising directly from a taproot, 0.5–1.2(–1.6) dm, tomentose to floccose.

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, in well-defined rosettes;

petiole 1–4(–5.5) cm, tomentose to floccose;

blade ovate to obovate, 2.5–4(–5) × 1.6–2.5(–3.5) cm, densely white- to grayish- or reddish-tomentose abaxially, less so to floccose or glabrous and greenish adaxially, margins entire, 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.

2-umbellate, 5–10 × 5–10 cm;

branches tomentose to floccose;

bracts 3–5 at proximal node, leaflike, 1.5–2.5(–3.5) × 0.3–0,8(–1) cm, sometimes absent immediately below involucre.

Peduncles

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

Involucres

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

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

1 per node, campanulate, 8–11(–13) × 8–12 mm, thinly tomentose to lanate;

teeth 6–10, usually lobelike, mostly reflexed, 2–6 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.

7–9 mm, including 0.1–0.4 mm stipelike base;

perianth creamy yellow to pale yellowish, glabrous;

tepals monomorphic, oblong-obovate;

stamens exserted, 7–9 mm;

filaments pilose proximally.

Achenes

brown, lenticular, 1.5–1.9 mm, glabrous;

beak not exserted beyond tepals.

light brown to brown, 6–8 mm, glabrous.

Eriogonum inerme

Eriogonum robustum

Phenology Flowering Jun–Aug.
Habitat Heavy clayey slopes, montane and subalpine conifer woodlands
Elevation 1300-2000(-2500) m (4300-6600(-8200) ft)
Distribution
from FNA
CA; ID
[WildflowerSearch map]
[BONAP county map]
from FNA
NV
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

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

Of conservation concern.

Eriogonum robustum is restricted primarily to altered andesite soils in west-central Nevada, essentially at the confluence of Carson City, Lyon, Storey, and Washoe counties. There, due to the unusual soil, the plants typically occur in areas without sagebrush but among conifer species usually found at higher elevations. The species is cultivated infrequently and is a food plant for the intermediate dotted-blue butterfly (Euphilotes intermedia).

(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. 375.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oligogonum
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. 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. 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 E. lobbii var. robustum
Name authority (S. Watson) Jepson: Fl. Calif. 1: 406. (1914) Greene: Bull. Calif. Acad. Sci. 1: 126. (1885)
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