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flat top buckwheat, yucca buckwheat, yucca wild buckwheat

woolly-cup wild buckwheat, woollycup buckwheat

Habit Shrubs, erect, not scapose, 3–10(–12) × 3–6(–8) dm, tomentose or glabrous, grayish or greenish. Herbs, erect or matted, sometimes scapose, 1–3.5 × 1–2 dm or 0.05–0.2 × 0.5–3.5 dm, floccose or silky-tomentose, grayish.
Stems

erect, without persistent leaf bases, up to 1/2 or more height of plant;

caudex stems absent;

aerial flowering stems erect, slender, solid, not fistulose, 0.5–2 dm, tomentose or glabrous.

spreading or matted, occasionally with persistent leaf bases, up to 1/4 or more height of plant;

caudex stems matted;

aerial flowering stems erect or nearly so, slender, solid, not fistulose, 1–2 dm and floccose, or (0.1–)0.02–0.5(–0.65) dm and silky-tomentose.

Leaves

basal and cauline, 1 per node;

petiole 0.1–0.5 cm, mostly tomentose;

blade oblanceolate, 0.6–1.5 × 0.2–0.3 cm, tomentose on both surfaces, occasionally slightly less so adaxially, margins plane.

basal, 1 per node or fasciculate in terminal tufts;

petiole 0.1–2.5(–3) cm, tomentose to floccose;

blade lanceolate or oblanceolate to narrowly elliptic, 1–2.5(–3) × 0.3–0.5(–0.8) cm, or 0.4–1.2 × 0.1–0.3(–0.35) cm, densely white- or silvery-tomentose on both surfaces, margins plane.

Inflorescences

cymose, flat-topped and in tiers, 15–40 × 15–40 cm;

branches dichotomous, divaricately arranged in a zig-zag pattern, tomentose or glabrous;

bracts 3, scalelike, 1–7 mm.

capitate, subcapitate, umbellate-cymose, or cymose, 2–20 × 2–20 cm, floccose or, if matted, 0.3–1 × 0.3–1 cm;

branches open and divided 1–3 times, 2–20 cm, floccose or if matted, (0–)0.3–0.85 cm, silky-tomentose;

bracts 3, scalelike, triangular, (0.5–)1–3 mm.

Peduncles

absent.

absent or erect, slender, 2–15 mm, floccose.

Involucres

1 per node, turbinate, 2–2.5 × 1.5–2 mm, glabrous;

teeth 5, erect, 0.4–0.6 mm.

1 per node or 2–5 per cluster, broadly campanulate, 1.5–4 × (2–)3–6(–8) mm, tomentose;

teeth 5, erect to spreading, 1–1.5 mm.

Flowers

2–2.5 mm;

perianth white to pale yellow, glabrous;

tepals connate proximal 1/4 dimorphic, those of outer whorl obovate, those of inner whorl oblong;

stamens exserted, 2–4 mm;

filaments pilose proximally.

2.5–5(–6) mm;

perianth yellow, densely white-pubescent;

tepals connate proximal 1/3, monomorphic, lanceolate to broadly lanceolate;

stamens exserted, 3.5–5 mm;

filaments glabrous.

Achenes

light brown to brown, 2.5–3 mm, glabrous.

brown to dark brown, 3–4 mm, villous to tomentose.

Eriogonum plumatella

Eriogonum lachnogynum

Phenology Flowering Apr–Oct.
Habitat Sandy flats, washes, and slopes, mixed grassland, saltbush, blackbrush, and creosote bush communities, oak and pinyon-juniper woodlands
Elevation 400-1700 m (1300-5600 ft)
Distribution
from FNA
AZ; CA; NV
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; KS; NM; OK; TX
[WildflowerSearch map]
[BONAP county map]
Discussion

Eriogonum plumatella is encountered infrequently, primarily on the Mojave Desert, where it occurs in two forms, one with pubescent (var. plumatella) and one with glabrous (var. jaegeri) inflorescence branches. As both forms occur occasionally in the same population, the varieties are not considered to be taxonomically significant. Eriogonum plumatella occurs from Kern County, California, south through Los Angeles (including the foothills of the San Gabriel Mountains), San Bernardino, and Riverside counties to eastern San Diego County. To the east the species is found in Clark County, Nevada, and Mohave and western Yavapai counties, Arizona. A single specimen (Palmer s.n., GH) reportedly was gathered in Utah. Repeated efforts to find the plant in Washington County, Utah, have been unsuccessful, and the record is discounted here.

This species is the food plant for the rare pallid dotted-blue butterfly (Euphilotes pallescens pallescens). According to M. L. Zigmond (1981), the Kawaiisu pounded the seeds into a powder and made a mush. Given the small size of the achenes, and the paucity of large populations, the task of gathering sufficient seed must have been daunting. In taste, these seeds differ little from other, more common members of wild buckwheat, so it is likely that achenes of several species were gathered and processed into a watery meal.

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

Varieties 3 (3 in the flora).

The Navajo or Diné people consider Eriogonum lachnogynum to be a “life medicine,” making a concoction of shredded roots for the treatment of internal, and some external, ailments. It is often given for diarrhea.

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

Key
1. Plants erect; inflorescences subcapitate, umbellate-cymose, or cymose; flowering stems 1-2 dm at full anthesis; leaf blades 1-2.5(-3) × 0.3-0.5(-0.8) cm; widespread, not in Arizona
var. lachnogynum
1. Plants cespitose mats; inflorescences capitate; flowering stems 0.01-0.65 dm at full anthesis; leaf blades 0.4-1.2 × 0.1-0.35 cm; Arizona, New Mexico
→ 2
2. Flowering stems 0.1-0.5(-0.65) dm, longer than leaves
var. sarahiae
2. Flowering stems (0.01-)0.02-0.05(-0.12) dm, shorter than or just exceeding leaves
var. colobum
Source FNA vol. 5, p. 308. FNA vol. 5, p. 286.
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. 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. 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. lachnogynum var. colobum, E. lachnogynum var. lachnogynum, E. lachnogynum var. sarahiae
Synonyms E. plumatella var. jaegeri
Name authority Durand & Hilgard: J. Acad. Nat. Sci. Philadelphia, n. s. 3: 45. (1855) Torrey ex Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 8. (1856)
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