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bear buckwheat, Bear Valley buckwheat, Bear Valley wild buckwheat

Thorne's buckwheat, Thorne's wild buckwheat

Habit Herbs, spreading, matted, synoecious, 0.5–4 × (1.5–)2–8(–12), thinly tomen-tose to floccose or glabrate. Subshrubs, spreading and matted, not scapose, 0.4–0.8 × 0.4–1(–2.5) dm.
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.

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

caudex stems compact;

aerial flowering stems spreading, slender, solid, not fistulose, 0.1–0.2 dm, floccose to slightly tomentose.

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.

cauline, 1 per node or fasciculate;

petiole 0.01–0.02 cm, tomentose;

blade linear, 0.4–0.6 × 0.05–0.1 cm, densely white-tomentose adaxially, finely villous and green adaxially, margins revolute.

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.

umbellate-cymose, compact, 0.5–1 × 0.5–1 cm;

branches usually dichotomous, otherwise with secondaries suppressed, glabrous or nearly so;

bracts 3, scalelike, linear, 0.5–1 mm.

Peduncles

absent.

Involucres

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

teeth 5–8, erect, 0.5–2 mm.

1 per node, turbinate, 1.5–2 × 1–1.5 mm, floccose;

teeth 5, erect, 0.4–0.6 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, glabrous;

tepals connate proximal 1/4, dimorphic, those of outer whorl obovate, 1–1.5 mm wide, those of inner whorl oblanceolate, 0.8–1 mm wide, connate proximally;

stamens slightly exserted, 2–3 mm;

filaments pilose proximally.

Achenes

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

light brown, 2–2.5 mm, glabrous except for papillate beak.

Eriogonum ursinum

Eriogonum thornei

Phenology Flowering May–Jul.
Habitat Copper-rich quartzite gravel on ridges, pinyon woodlands
Elevation 1800 m (5900 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 thornei is known from a single canyon area in the New York Mountains, San Bernardino County. Shultz elevated Thorne’s wild buckwheat to species status when she proposed E. phoeniceum, here considered a variety of E. microthecum. Eriogonum thornei and E. ericifolium are weakly differentiated, with minimal morphologic differences, and yet they occur on different substrates and are well-removed biogeographically from each other. Thorne’s wild buckwheat is a protected plant in California.

(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. 255.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oligogonum 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. 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. 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. 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
Synonyms E. ericifolium var. thornei, E. ericifolium subsp. thornei
Name authority S. Watson: Proc. Amer. Acad. Arts 10: 347. (1875) (Reveal & Henrickson) L. M. Shultz: Harvard Pap. Bot. 3: 51. (1998)
Web links