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bear buckwheat, Bear Valley buckwheat, Bear Valley wild buckwheat

clay buckwheat, clay loving buckwheat, Coast Range wild buckwheat

Habit Herbs, spreading, matted, synoecious, 0.5–4 × (1.5–)2–8(–12), thinly tomen-tose to floccose or glabrate. Herbs, erect, 1–3 dm, glabrous or rarely sparsely floccose, mostly greenish.
Stems

caudex spreading;

aerial flowering stems erect, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, non-flowering aerial branches, 0.4–4 dm, thinly tomentose to floccose or glabrate.

aerial flowering stems erect, (0.3–)0.5–1.5(–2.5) dm, glabrous, rarely sparsely floccose.

Leaves

in rather compact basal rosettes;

petiole 0.1–1.5 cm, tomentose;

blade elliptic, 0.7–2(–2.2) × 0.4–1(–1.2) cm, or ovate, 0.8–1.4(–2.5) × 0.5–1.2(–2) cm, densely white- or rufous-tomentose abaxially, thinly tomentose, sparsely floccose, or glabrous and greenish adaxially, margins slightly wavy.

basal and cauline;

basal: petiole (0.5–)1–4(–5) cm, sparsely floccose, blade oblong, 1–3(–5) × 0.3–1.2(–1.6) cm, densely white-tomentose abaxially, floccose to glabrate and greenish adaxially;

cauline: petiole 0.3–2 cm, sparsely floccose, blade elliptic to oblong, 0.5–1.5 × 0.2–0.8 cm, similar to basal blade.

Inflorescences

compound-umbellate, 1–3(–6) × 1–5 cm, thinly tomentose to glabrate;

bracts: proximal 3–8, lanceolate to narrowly elliptic, 0.5–2 × 0.25–1 cm, distal 3, semileaflike, midway along branch, linear to narrowly lanceolate, 0.7–1 × 0.1–0.25 cm, or ± scalelike below involucre, 1–5 mm.

cymose, occasionally distally uniparous due to suppression of secondary branches, open, (2–)5–20(–25) cm;

branches glabrous or rarely sparsely floccose;

bracts 1–5(–7) × 0.5–1(–1.5) mm.

Peduncles

erect, straight, slender, 0.5–4.5(–6) cm, glabrous.

Involucres

1 per node, turbinate to turbinate-campanulate, 3.5–8 × 2.5–4 mm, villous;

teeth 5–8, erect, 0.5–2 mm.

terminal at tips of slender branchlets proximally, not appressed to branches, turbinate, (2–)2.5–3 × 2–3 mm, glabrous;

teeth 5, erect, 0.2–0.5 mm.

Flowers

5–7 mm at anthesis, 6.5–9 mm in fruit, including 0.5–0.8 mm stipelike base, with perianth cream or rarely yellow, suffused with blush of pinkish red to maroon, glabrous, or flowers 4–6 mm, including 1–1.3 mm stipelike base, with perianth pale yellow or rarely yellow, not suffused with blush of color glabrous;

tepals slightly dimorphic or monomorphic, broadly ovate or obovate;

stamens exserted, 3–5 mm;

filaments pilose proximally.

1.5–2 mm;

perianth white to rose, glabrous;

tepals monomorphic, oblong;

stamens mostly included, 1–2 mm;

filaments glabrous;

styles 0.2–0.3 mm.

Achenes

light brown, (5–)5.5–8 mm or 3–3.5 mm, glabrous except for sparsely pubescent beak.

brown, 3-gonous, 2–2.5 mm, glabrous;

beak smooth.

Eriogonum ursinum

Eriogonum argillosum

Phenology Flowering Mar–Oct.
Habitat Clay to serpentine outcrops and slopes, mixed grassland and chaparral communities, oak and pine woodlands
Elevation 100-600 m (300-2000 ft)
Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

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

Eriogonum argillosum is rare to locally infrequent in coastal central California. It was last seen in Santa Clara County in 1895 and now is almost certainly extirpated there. Otherwise, it is found in the San Benito River Canyon (San Benito County) area and east of San Lucas (Monterey County). This is the most distinct of the five species in the E. eastwoodianum complex.

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

Key
1. Flowers 5-9 mm, perianth cream, rarely yellow; achenes (5-)5.5-8 mm; North Coast Ranges, Siskiyou and Trinity counties
var. erubescens
1. Flowers 4-6 mm, perianth pale yellow or rarely yellow; achenes 3-3.5 mm; n Sierra Nevada, Lassen and Shasta counties to Nevada, Placer, Plumas, and Sierra counties
var. ursinum
Source FNA vol. 5, p. 358. FNA vol. 5, p. 419.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oligogonum Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oregonium
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. 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. 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. 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. 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. ursinum var. erubescens, E. ursinum var. ursinum
Name authority S. Watson: Proc. Amer. Acad. Arts 10: 347. (1875) J. T. Howell: Leafl. W. Bot. 1: 13. (1932)
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