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alpine buckwheat, alpine eriogonum, alpine wild buckwheat, dirty socks, oarleaf buckwheat, oarleaf wild buckwheat, pyrola-leaf buckwheat, pyrola-leafed wild buckwheat, Shasta buckwheat, Shasta wild buckwheat

San Pedro River wild buckwheat

Habit Herbs, compact or spreading, matted, 0.3–2 × 0.5–3 dm, floccose or glabrous. Shrubs, sprawling to erect, not scapose, 1–4(–5) × (1–)2–6(–9) dm, thinly tomentose or floccose to subglabrous, greenish.
Stems

caudex absent or spreading;

aerial flowering stems prostrate to weakly erect, slender, solid, not fistulose, usually arising directly from a taproot, 0.3–1.5(–1.8) dm, villous to floccose or glabrous.

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

caudex stems absent;

aerial flowering stems erect or nearly so, slender, solid, not fistulose, 0.05–0.3 dm, thinly tomentose.

Leaves

basal, mostly in loose rosettes;

petiole 1–4 cm, tomentose to floccose;

blade ovate to round, 1–2.5(–4) × 0.8–2 cm, grayish- to tannish-lanate or tomentose abaxially, glabrous and green adaxially, or glabrous on both surfaces, margins entire, plane.

cauline, fasciculate;

petiole 0.05–0.1 cm, glabrous;

blade linear-oblanceolate or linear-elliptic, 0.3–0.8(–1) × (0.05–)0.1–0.2 cm, densely white-tomentose abaxially, thinly floccose or glabrous and greenish adaxially, margins rolled.

Inflorescences

capitate or umbellate, 1–3(–5) × 1–4 cm;

branches floccose or glabrous;

bracts 2, leaflike, (0.4–)1–2 × 0.1–0.2(–0.4) cm, sometimes absent immediately below involucre.

cymose, compact, 1–3 × 1–3 cm;

branches dichotomous, thinly tomentose;

bracts 3, scalelike, triangular, (0.5–)1–2 mm.

Peduncles

absent or erect, 0.1–0.8(–1) cm, thinly tomentose.

Involucres

1 per node (occasionally appearing clustered), campanulate, 4–6 × (3–)4–8 mm, pilose or glabrous;

teeth 4–5, erect, 0.6–1 mm.

1 per node, campanulate, 3–4.5 × 2.5–3.5 mm wide, thinly tomentose to subglabrous;

teeth 5, erect, 0.5–1.2 mm.

Flowers

4–6 mm, including 0.1–0.2 mm stipelike base;

perianth white to rose, pilose to villous with intermixed glandular hairs abaxially;

tepals monomorphic, obovate;

stamens exserted, 4–8 mm;

filaments pilose proximally.

3.5–4.5(–5) mm;

perianth white, glabrous;

tepals connate proximal 1/3, dimorphic, those of outer whorl broadly cordate, 2–3 mm wide, apex rounded, those of inner whorl oblanceolate, 1–2 mm wide;

stamens exserted, 3.5–4.5 mm;

filaments pilose proximally.

Achenes

light brown to brown, 4–5 mm, glabrous except for pilose beak.

light brown, 4–4.5 mm, glabrous.

Eriogonum pyrolifolium

Eriogonum terrenatum

Phenology Flowering Aug–Nov.
Habitat Clayey slopes and flat, creosote bush communities
Elevation 1000-1200 m (3300-3900 ft)
Distribution
from FNA
CA; ID; MT; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

The taxonomic merit of the two varieties of Eriogonum pyrolifolium is dubious. Plants with both hairy and nonhairy leaves are found growing together, and yet there are many populations in which only a single expression is found.

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

Eriogonum terrenatum is confined to two geographically separate areas. Near Vail, Pima County, it is restricted to clayey outcrops of the Pantano Formation, whereas near Fairbanks, Cochise County, it is confined to the eroded, clay slopes and flats of the Saint David Formation.

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

Key
1. Leaf blades densely lanate to tomentose abaxially, mostly glabrous adaxially
var. coryphaeum
1. Leaf blades glabrous on both surfaces
var. pyrolifolium
Source FNA vol. 5, p. 374. FNA vol. 5, p. 254.
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. 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. 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. pyrolifolium var. coryphaeum, E. pyrolifolium var. pyrolifolium
Name authority Hooker: Hooker’s J. Bot. Kew Gard. Misc. 5: 395, plate 10. (1853) Reveal: Phytologia 86: 144. (2004)
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