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slender buckwheat, slender woolly buckwheat, slender woolly wild buckwheat

pagoda buckwheat, pagoda wild buckwheat, Rixford's buckwheat

Habit Herbs, erect to spreading or somewhat decumbent, (0.7–)1.5–5(–7) dm, lanate to tomentose or floccose, rarely glabrous, greenish to whitish or grayish. Herbs, erect, annual, (1.5–)2–4 dm, glabrous, greenish to grayish.
Stems

aerial flowering stems erect, 0.5–2 dm, lanate to tomentose or floccose, rarely glabrous.

caudex absent;

aerial flowering stems erect, solid, not fistulose, 0.3–2 dm, glabrous.

Leaves

basal and cauline;

basal: petiole 1–4 cm, floccose, not winged, blade oblanceolate to oblong, (0.8–)1–4(–6) × 0.5–2 cm, tomentose abaxially, less so to floccose and greenish to grayish adaxially;

cauline: petiole 0.3–2 cm, floccose, blade oblanceolate, 0.5–3 × 0.3–1.5 cm, similar to basal blade.

basal;

petiole 1–3(–5) cm, floccose;

blade cordate to orbiculate, (0.5–)1–3 × (0.5–)1–3 cm, densely white-tomentose abaxially, less so to subglabrous and grayish to greenish adaxially, margins entire.

Inflorescences

cymose, occasionally distally uniparous due to suppression of secondary branches, open to somewhat diffuse, 0.5–4 × 0.5–3 cm;

branches lanate to tomentose or floccose, rarely glabrous, straight or nearly so, not inwardly curved distally;

bracts 0.5–3 × 1–3 mm.

cymose, diffuse, of many horizontal tiers of flat-topped branches, 10–35 × 5–35 cm;

branches glabrous;

bracts 3, scalelike, 1–3 × 0.5–1.5 mm.

Peduncles

absent.

absent.

Involucres

somewhat appressed to branches, turbinate, (1.8–)2–3 × 1.5–2 mm, floccose or glabrous;

teeth 5, erect, 0.3–0.6 mm.

deflexed, narrowly campanulate, 1–1.5 × 1.5–2 mm, glabrous;

teeth 5, erect, 0.4–0.7 mm.

Flowers

1.5–3 mm;

perianth white to pink or yellow, glabrous;

tepals monomorphic, lanceolate to oblong;

stamens mostly included, 1–1.5 mm;

filaments pilose proximally.

1.3–1.5 mm;

perianth white with greenish midribs, becoming reddish, glabrous;

tepals dimorphic, those of outer whorl narrowly oval to cordate, those of inner whorl narrowly lanceolate;

stamens included, 1–1.3 mm;

filaments glabrous.

Achenes

brown, 3-gonous, 1–2 mm.

dark brown, lenticular, 1.3–1.5 mm, glabrous.

2n

= 22.

= 40.

Eriogonum gracile

Eriogonum rixfordii

Phenology Flowering Jun–Dec.
Habitat Sandy to gravelly washes and slopes, saltbush communities
Elevation (30-)100-1600 m ((100-)300-5200 ft)
Distribution
from FNA
CA; Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Eriogonum gracile is a highly variable species. The low, spreading plants from the mountains of coastal central California with 2–3 mm involucres and (usually) yellowish flowers differ from the more erect plants represented by the type collection, which have 1.8–2 mm involucres and white flowers. Such plants are found mainly farther south, in the Mt. Diablo and Mt. Hamilton areas of Alameda, Contra Costa, and Stanislaus counties. Some populations of E. gracile from the Inner Coast Ranges of eastern San Luis Obispo County are slightly different from the norm and the epithet leucocladon has been adopted in some local floristic treatments to account for them. However, the type of E. leucocladon does not seem to be this phase.

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

Of conservation concern.

Eriogonum rixfordii is occasional in the Death Valley area of Inyo County, California, and adjacent southwestern Nye County, Nevada. Its habit is so striking that it is often collected as a novelty. It is rarely common and never weedy.

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

Key
1. Inflorescence branches lanate to tomentose or floccose; throughout California
var. gracile
1. Inflorescence branches glabrous; s California
var. incultum
Source FNA vol. 5, p. 423. FNA vol. 5, p. 396.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oregonium 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. 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. 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. 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. gracile var. gracile, E. gracile var. incultum
Synonyms E. vimineum subsp. gracile E. deflexum subsp. rixfordii
Name authority Bentham: Bot. Voy. Sulphur, 46. (1844) S. Stokes: Leafl. W. Bot. 1: 29. (1932)
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