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

Crosby's buckwheat, Crosby's wild buckwheat

Habit Subshrubs, spreading, polygamodioecious, 0.5–2(–3) × 1–3(–4) dm, tomentose to sericeous. Herbs, matted, scapose, 0.05–1.5(–2) × (0.1–)1–3 dm, floccose to tomentose or glabrous, sometimes glandular, greenish or grayish.
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.

matted, with persistent leaf bases, up to 1/5 height of plant;

caudex stems matted;

aerial flowering stems scapelike, weakly erect to erect, slender, solid, not fistulose, 0.02–1.5(–1.8) dm, floccose to tomentose or glabrous, occasionally also or only sparsely to densely glandular.

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.

basal, fasciculate in terminal tufts;

petiole 0.2–3(–3.5) cm, tomentose, infrequently glandular;

blade oblanceolate to spatulate or elliptic to obovate or ovate, (0.5–)1–2(–3) × 0.2–1(–1.5) cm, densely white- or grayish-tomentose on both surfaces, sometimes less and greenish white adaxially, margins plane.

Inflorescences

capitate, 0.8–2 cm wide;

branches absent;

bracts absent immediately below involucre.

capitate, 0.7–1.5 cm;

branches absent;

bracts 3, narrowly triangular to triangular, scalelike, 1–3 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.

(3–)5–8 per cluster, turbinate to campanulate, (1.5–)2–5(–5.5) × 2–4(–4.5) mm, rigid or membranous, tomentose to floccose, occasionally glabrous except for floccose teeth, rarely sparsely pilose and glandular;

teeth 5–7, erect to spreading or reflexed, 0.5–1.5 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.

1.5–3.5(–4) mm, glabrous or occasionally minutely glandular, pustulose in some;

perianth yellow to pale yellow or, rarely, cream;

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

stamens exserted, 1.5–4 mm;

filaments glabrous or sparsely pilose proximally.

Achenes

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

light brown, 2–4 mm, glabrous or sometimes with minute bristles on beak.

2n

= 40.

Eriogonum thymoides

Eriogonum crosbyae

Phenology Flowering Apr–Jul. Flowering May–Aug.
Habitat Sandy to gravelly, often volcanic flats, slopes, and outcrops, mixed grassland and sagebrush communities, montane conifer woodlands White tuffaceous shale volcanic outcrops, metamorphic rock outcrops, or basaltic or granitic sandy flats, washes, slopes, and ridges, saltbush and sagebrush or high-elevation sagebrush to alpine tundra communities, juniper or montane conifer woodlands
Elevation (200-)600-1700 m ((700-)2000-5600 ft) (1200-)1400-3100
Distribution
from FNA
ID; OR; WA
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; MT; NV; OR
[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.)

Eriogonum crosbyae, as now defined, is widely scattered in the valley bottoms and foothills, and atop several mountain ranges of central Idaho (Blaine, Butte, Camas, Custer, and Lemhi counties) and in western Montana (Deer Lodge and Ravalli counties). It is disjunct to southwestern Idaho (Owyhee Mountains, Owyhee County), southeastern Oregon (Guano and Coleman valleys, Harney County, and Fish Fin Rim, Lake County), and in northwestern Nevada (Washoe and Humboldt counties south through Douglas, Lyon, and Pershing counties to Mineral County). It also occus in the Marys River Peak area of Elko County, Nevada.

The species may be subdivided into four phases, for which names are available. The vast majority of populations have bright yellow flowers with pustulose bases and midveins. The pustulose condition may also be observed in Eriogonum chrysops (on pale greenish-yellow flowers) and in E. mancum (with cream-colored flowers). Populations with pale yellow flowers here assigned to E. crosbyae occur in the mountains near Mackay, Idaho, and cream-colored flowers are found near Challis and around Salmon, both well outside the known ranges of E. chrysops and E. mancum. Final resolution of the taxonomy of this group awaits further study.

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

Source FNA vol. 5, p. 360. FNA vol. 5, p. 277.
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. 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
Synonyms E. sphaerocephalum subsp. minimum, E. thymoides subsp. congestum E. capistratum, E. capistratum var. muhlickii, E. capistratum var. welshii, E. meledonum, E. ochrocephalum var. alexanderae, E. verrucosum
Name authority Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 14: 9. (1856) Reveal: Brittonia 33: 442, fig. 1. (1981)
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