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

fine branch wild buckwheat, sand buckwheat, sand wild buckwheat

Habit Subshrubs, spreading, polygamodioecious, 0.5–2(–3) × 1–3(–4) dm, tomentose to sericeous. Shrubs, erect to spreading, not scapose, (2–)3–10(–12) × 5–15(–20) dm, white-tomentose to floccose, or green and nearly glabrous.
Stems

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.

spreading, often without persistent leaf bases, up to 1/2 height of plant;

caudex stems absent or spreading in moving sand;

aerial flowering stems spreading, slender, solid, not fistulose, 0.3–1 dm, white-tomentose, floccose to glabrate or glabrous.

Leaves

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.

cauline, 1 per node;

petiole 0.2–0.5 cm, tomentose to floccose;

blade linear-lanceolate to linear-oblanceolate to narrowly oblong, or lanceolate to narrowly elliptic, 1.5–4 × 0.2–0.8(–1.2) cm, densely white-tomentose abaxially, less so and greenish adaxially, margins plane, infrequently revolute.

Inflorescences

capitate, 0.8–2 cm wide;

branches absent;

bracts absent immediately below involucre.

cymose, open, 5–40 × 10–50 cm;

branches dichtomous proximally, often with involucres racemosely arranged proximally, tomentose to floccose or glabrate, occasionally glabrous;

bracts 3, scalelike, linear to triangular, 1–3(–6) mm.

Peduncles

absent.

Involucres

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

teeth 6–8, erect, 0.5–1 mm.

1 per node, turbinate to turbinate-campanulate, 1.5–3 × 1–2 mm, tomentose to floccose or glabrous;

teeth 5, erect, 0.4–0.7 mm.

Flowers

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.

(2–)2.5–3.5 mm;

perianth white or pale yellow to yellow, glabrous;

tepals connate proximal 1/4–1/3, essentially monomorphic, oblong to broadly obovate;

stamens slightly exserted, 2–4 mm;

filaments sparsely pilose proximally.

Achenes

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

light brown, 2.5–3.5 mm, glabrous except for minutely papillate beak.

Eriogonum thymoides

Eriogonum leptocladon

Phenology Flowering Apr–Jul.
Habitat Sandy to gravelly, often volcanic flats, slopes, and outcrops, mixed grassland and sagebrush communities, montane conifer woodlands
Elevation (200-)600-1700 m ((700-)2000-5600 ft)
Distribution
from FNA
ID; OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; NM; UT
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Varieties 3 (3 in the flora).

Eriogonum leptocladon is localized on moving sands on the Colorado Plateau. It is not unusual, therefore, for portions of the shrub to be buried in sand, especially the main, woody trunk from which the flowering stems arise. In the Four Corners area three species share portions of overlapping ranges, and herbarium material from there can be difficult to separate. In northwestern New Mexico, var. ramosissimum approaches E. effusum, and in eastern San Juan County the two can be distinguished only by the open, spreading inflorescence branching pattern of var. ramosissimum as compared to the densely branched, compact inflorescence of E. effusum. In the field, the former is confined to sandy areas whereas the latter is typically on heavier, usually clayey soils. In south-central Utah, var. ramosissimum approaches E. nummulare. There, both are found on moving sands, and only the degree of stoutness of the branches can be used to differentiate them when cauline leaves are absent. For the most part, the inflorescence branches of E. nummulare are more rigid and stouter than those of var. ramosissimum, which tend to be flexible and slender. When leaves are present, those of the former are broader and more apically rounded compared to those of the latter.

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

Key
1. Perianths pale yellow to yellow
var. leptocladon
1. Perianths white
→ 2
2. Flowering stems and inflorescence branches tomentose, rarely floccose
var. ramosissimum
2. Flowering stems and inflorescence branches glabrous
var. papiliunculi
Source FNA vol. 5, p. 360. FNA vol. 5, p. 249.
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. 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. 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. leptocladon var. leptocladon, E. leptocladon var. papiliunculi, E. leptocladon var. ramosissimum
Synonyms E. sphaerocephalum subsp. minimum, E. thymoides subsp. congestum E. effusum subsp. leptocladon
Name authority Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 9. (1856) Torrey & A. Gray: in War Department [U.S.], Pacif. Railr. Rep. 2(1): 129. (1857)
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