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slender buckwheat, slender woolly buckwheat, slender woolly wild buckwheat

Butterworth's buckwheat, Butterworth's wild 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. Subshrubs, rarely scapose, 1–3 × 1–4 dm, tomentose, grayish to reddish.
Stems

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

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 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.

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, 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-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

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

teeth 5, erect, 0.3–0.6 mm.

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

teeth 5, erect, 1–2 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.

(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

brown, 3-gonous, 1–2 mm.

brown, 3–3.5 mm, glabrous.

2n

= 22.

Eriogonum gracile

Eriogonum butterworthianum

Phenology Flowering Jun–Sep.
Habitat Sandstone outcrops, chaparral communities, oak and conifer woodlands
Elevation 600-700 m (2000-2300 ft)
Distribution
from FNA
CA; Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[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 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.)

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. 294.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oregonium 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. 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. 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
Subordinate taxa
E. gracile var. gracile, E. gracile var. incultum
Synonyms E. vimineum subsp. gracile
Name authority Bentham: Bot. Voy. Sulphur, 46. (1844) J. T. Howell: Leafl. W. Bot. 9: 153. (1961)
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