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flat top buckwheat, yucca buckwheat, yucca wild buckwheat

thyme buckwheat, thyme wild buckwheat, thyme-leaf buckwheat, thyme-leaf wild buckwheat

Habit Shrubs, erect, not scapose, 3–10(–12) × 3–6(–8) dm, tomentose or glabrous, grayish or greenish. Subshrubs, spreading, polygamodioecious, 0.5–2(–3) × 1–3(–4) dm, tomentose to sericeous.
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.

caudex spreading;

aerial flowering stems erect, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, nonflowering aerial branches, (0.1–)0.3–0.8(–1.2) dm, tomentose to sericeous, with a whorl of 6–10(–12), leaflike bracts ca. midlength, these similar to leaf blades, 0.3–0.8(–1) × 0.1–0.2 cm.

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.

in compact basal rosettes, fasciculate, and sheathing up stems;

petiole 0.05–0.2 cm;

blade linear to narrowly spatulate, (0.2–)0.3–1(–1.5) × 0.1–0.2(–0.3) cm, densely white-tomentose abaxially, silky-villous or sericeous adaxially, margins entire, inrolled to tightly revolute.

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, 0.8–2 cm wide;

branches absent;

bracts absent immediately below involucre.

Peduncles

absent.

Involucres

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

teeth 5, erect, 0.4–0.6 mm.

1 per node, turbinate, 3–5 × 2.5–4 mm, villous to sericeous;

teeth 6–8, erect, 0.5–1 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.

4–10 mm, including 0.5–1 mm stipelike base;

perianth white to pale yellow or yellow, becoming pink to rose, villous abaxially;

tepals monomorphic, obovate;

stamens included to slightly exserted, 2–4 mm;

filaments pilose proximally.

Achenes

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

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

Eriogonum plumatella

Eriogonum thymoides

Phenology Flowering Apr–Oct. Flowering Apr–Jul.
Habitat Sandy flats, washes, and slopes, mixed grassland, saltbush, blackbrush, and creosote bush communities, oak and pinyon-juniper woodlands Sandy to gravelly, often volcanic flats, slopes, and outcrops, mixed grassland and sagebrush communities, montane conifer woodlands
Elevation 400-1700 m (1300-5600 ft) (200-)600-1700 m ((700-)2000-5600 ft)
Distribution
from FNA
AZ; CA; NV
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; OR; WA
[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.)

Eriogonum thymoides is an exquisite species concentrated in three regions of the Pacific Northwest. The first is along the eastern edge of the Cascade Range from near Wenatchee, Washington (Adams, Benton, Chelan, Douglas, Franklin, Grant, Kittitas, Klickitat, Lincoln, and Yakima counties), to near the Dalles in extreme north-central Oregon (Union County). The second is from Baker and northern Malheur counties, Oregon, to Adams, Canyon, and Washington counties, Idaho. A third series of populations is in the Mount Bennett Hills area of Gooding County, Idaho, and just over the borders in Blaine, Camas, Elmore, and Lincoln counties. Staminate plants tend to have yellow flowers that quickly fade after pollen release. Pistillate plants tend to have white to pale yellow flowers that persist and greatly elongate as the achene matures.

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

Source FNA vol. 5, p. 308. FNA vol. 5, p. 360.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oligogonum
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. 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. 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. plumatella var. jaegeri E. sphaerocephalum subsp. minimum, E. thymoides subsp. congestum
Name authority Durand & Hilgard: J. Acad. Nat. Sci. Philadelphia, n. s. 3: 45. (1855) Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 9. (1856)
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