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hoary buckwheat, hoary wild buckwheat, rock buckwheat

Butterworth's buckwheat, Butterworth's wild buckwheat

Habit Herbs, loosely to densely matted, not scapose, (1–)2–4 × 0.5–2 dm, densely white- or grayish-lanate to tomentose or floccose. Subshrubs, rarely scapose, 1–3 × 1–4 dm, tomentose, grayish to reddish.
Stems

spreading, often with persistent leaf bases, up to 1/4 height of plant;

caudex stems matted, decumbent to spreading;

aerial flowering stems spreading to erect, slender, solid, not fistulose, 0.5–1.5 dm, lanate to tomentose or floccose.

slightly spreading to erect, without persistent leaf bases, up to 1/4 height of plant;

caudex stems absent;

aerial flowering stems erect, slender, solid, not fistulose, 0.1–0.3 dm, tomentose.

Leaves

basal or sheathing up stems 4 cm, 1 per node or fasciculate at tips of caudex branches;

proximal leaves: petiole 1–3(–4) cm, tomentose, blade obovate to rounded, 1–2(–2.5) × 1–2 cm, lanate to tomentose;

distal leaves sessile, blade elliptic to rounded, 0.3–1 × 0.3–1 cm, lanate to tomentose.

sheathing up stem 0.5–1.5 cm, 1 per node;

petiole 0.1–0.3 cm, tomentose;

blade linear to narrowly elliptic, (0.5–)1–2 × 0.1–0.4 cm, grayish- to reddish-brown-tomentose, margins revolute.

Inflorescences

cymose, 10–25 × 5–12 cm;

branches dichotomous, lanate to tomentose or floccose;

bracts 3–4, scalelike, triangular, 1.5–7 mm.

cymose-umbellate to cymose, rarely capitate, often with involucres racemosely disposed at tips, usually 1–2 × 1–2 cm;

branches dichotomous, rarely scapelike, tomentose;

bracts 3, scalelike, narrowly triangular, (1–)2–4(–5) mm.

Peduncles

absent.

absent.

Involucres

1 per node, turbinate, 3–4 × 2–3 mm, tomentose to floccose;

teeth 5–6, erect, 0.8–1.5 mm.

1 per node, turbinate to turbinate-campanulate, (4–)5–6 × 3–4 mm, tomentose;

teeth 5, erect, 1–2 mm.

Flowers

(3–)5–7 mm, including elongate, sharply triangular, slightly winged, stipelike base;

perianth white to rose or yellowish, glabrous;

tepals connate proximally, dimorphic, those of outer whorl oblanceolate to lanceolate, 3–5 × 1.5–2 mm, those of inner whorl obovate, 4–6 × 2–3 mm;

stamens included to slightly exserted, 2.5–5 mm;

filaments pilose proximally.

(3–)4–5 mm;

perianth ochroleucous to rose, glabrous;

tepals connate proximal 1/4, monomorphic, obovate;

stamens exserted, 5–6 mm;

filaments pubescent proximally.

Achenes

3-gonous, nearly winged, 3.5–4 mm, glabrous.

brown, 3–3.5 mm, glabrous.

2n

= 40.

Eriogonum saxatile

Eriogonum butterworthianum

Phenology Flowering May–Oct. Flowering Jun–Sep.
Habitat Decomposed granitic or volcanic flats, slopes, and ridges, chaparral, saltbush, and sagebrush communities, pinyon-juniper and montane conifer woodlands Sandstone outcrops, chaparral communities, oak and conifer woodlands
Elevation (300-)800-3400(-3500) m ((1000-)2600-11200(-11500) ft) 600-700 m (2000-2300 ft)
Distribution
from FNA
CA; NV
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Eriogonum saxatile is found mainly in arid mountains of California (Fresno, Inyo, Kern, Los Angeles, Mono, Monterey, Riverside, San Benito, San Bernardino, Santa Barbara, Tulare, and Ventura counties) and Nevada (Esmeralda and western Nye counties). The plants vary considerably as to robustness, degree of branching, and sprawl of the caudex. The size and position of the leaves also vary, as does the density of tomentum on the blades. Flower color varies from white to rose or yellowish, but the deep yellow of E. crocatum is never seen in E. saxatile. The species is frequently cultivated and is an excellent plant for the rock garden.

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

Of conservation concern.

Eriogonum butterworthianum is a rare and localized species that grows in the cracks of Vaqueros sandstone near The Indians in the Santa Lucia Range of Monterey County. It is considered a “sensitive species” by the U.S. Forest Service. Its relationship to other species in subg. Eucycla is uncertain. Butterworth’s wild buckwheat would make an elegant addition to the garden. Given its rarity, great care must be taken even in collecting seeds.

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

Source FNA vol. 5, p. 324. FNA vol. 5, p. 294.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla 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. 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. robustum, E. rosense, E. roseum, E. rotundifolium, E. rubricaule, E. rupinum, E. salicornioides, 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. 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. 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
Synonyms E. saxatile subsp. multicaule
Name authority S. Watson: Proc. Amer. Acad. Arts 12: 267. (1877) J. T. Howell: Leafl. W. Bot. 9: 153. (1961)
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