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Heerman buckwheat, Heermann's buckwheat, Heermann's wild buckwheat

Siskiyou buckwheat, Siskiyou wild buckwheat

Habit Shrubs and subshrubs, spreading to rounded and occasionally erect, not scapose, (0.5–)1–20 × 2–25 dm, glabrous or occasionally floccose, sometimes scabrellous, greenish, infrequently grayish. Herbs, spreading, matted, 0.5–2 × 1–5 dm, glabrate or glabrous.
Stems

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 to stout, solid, not fistulose, 0.02–0.5 dm, thinly 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, non-flowering aerial branches, 0.5–1.5(–2) dm, usually glabrous, with a whorl of 2–4 leaflike bracts ca. midlength, similar to leaf blade, 0.3–0.5 × 0.1–0.2 cm.

Leaves

cauline, 1 per node, quickly deciduous;

petiole 0.1–1.5 cm, floccose or glabrous;

blade linear, oblanceolate or spatulate or elliptic, or oblong, (0.4–)1–2(–4) × 0.1–0.8 cm, tomentose to floccose or glabrous abaxially, floccose to thinly floccose or glabrous adaxially, margins plane.

in dense compact basal rosettes;

petiole 0.2–0.6 cm, glabrate or glabrous;

blade spatulate to round, (0.3–)0.5–0.8 × (0.2–)0.3–0.5(–0.7) cm, densely white to thinly tomentose abaxially, sparsely floccose to glabrate and green or olive green adaxially, rarely glabrous on both surfaces, margins entire, plane.

Inflorescences

cymose or racemose, 1–25(–30) × 1–30(–35) cm;

branches dichotomous, sometimes with secondaries suppressed, smooth or angled to ridged and grooved, glabrous or occasionally floccose or scabrous;

bracts 3, scalelike, 0.3–2 mm.

capitate, rarely umbellate, 0.8–1.5 cm wide or 1–2 × 1–3 cm;

branches usually glabrate;

bracts absent immediately below involucre.

Peduncles

absent.

Involucres

1 per node, narrowly turbinate or campanulate, 0.7–3 × 0.7–4 mm, glabrous, infrequently floccose;

teeth 5, erect, 0.3–0.7 mm.

1 per node, turbinate-campanulate to campanulate, (3–)3.5–4 × 4–6 mm, arachnoid-tomentose;

teeth 6–10, lobelike, reflexed, (2–)2.5–3.5 mm.

Flowers

(1.5–)2–4 mm;

perianth white, yellowish white, pink, or reddish, glabrous;

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

stamens exserted, 2–5 mm;

filaments pilose proximally.

(4–)4.5–6 mm, including 0.6–1 mm stipelike base;

perianth sulphur yellow, glabrous;

tepals monomorphic, oblong;

stamens exserted, 3.5–5 mm;

filaments pilose proximally.

Achenes

light brown to brown, 2–5 mm, glabrous.

light brown, 4.5–5 mm, glabrous.

Eriogonum heermannii

Eriogonum siskiyouense

Phenology Flowering Jul–Sep.
Habitat Gravelly serpentine slopes and outcrops, manzanita communities, montane conifer woodlands
Elevation 1600-2800 m (5200-9200 ft)
Distribution
from FNA
AZ; CA; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Varieties 8 (8 in the flora).

As Eriogonum heermannii is here circumscribed, the number of varieties is dramatically decreased from past presentations, with E. apachense reduced to synonymy under a now greatly expanded var. argense. Also included in that variety is the more stoutly branched var. subracemosum. The southern var. heermannii of basically desert ranges and the more northern var. occidentale of the Coast Ranges in California are maintained, but their separation is more traditional than certain. The fragile and bulky nature of many dried, often poorly prepared specimens, and the tendency for leaves to fall away have made varietal identification within E. heermannii difficult.

Eriogonum heermannii varieties are food plants for Ellis’s dotted-blue butterfly (Euphilotes ellisi) and the Mormon metalmark (Apodemia mormo mormo).

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

Eriogonum siskiyouense is restricted to the ridge system that extends from the Scott Mountain area to the Mt. Eddy region of Siskiyou and Trinity counties. The vast majority of individuals in a population have a single involucre atop each flowering stem, but at lower elevations and in somewhat more protected sites the inflorescence may be umbellate. The Siskiyou wild buckwheat does well in cultivation if its soil requirements are fulfilled.

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

Key
1. Flowering stems and inflorescence branches round or angled, scabrellous or papillate-scabrous; plants often densely branched
→ 2
1. Flowering stems and inflorescence branches round, not angled, usually smooth, glabrous or thinly tomentose; plants sparsely branched
→ 3
2. Flowering stems and inflorescence branches round, usually distinctly scabrellous or infrequently papillate-scabrous; Arizona, se California, Nevada
var. argense
2. Flowering stems and inflorescence branches sharply ridged and deeply grooved, minutely scabrellous; nw Arizona, se California, s Nevada, sw Utah
var. sulcatum
3. Involucres not racemosely arranged on inflorescence branches, or only last 2-3 so disposed; inflorescences diffusely branched, glabrous; Great Basin or northeast edge of Mojave Desert
→ 4
3. Involucres racemosely arranged along inflorescence branches or at least at tips of branches; inflorescences openly branched, glabrous or floccose to thinly tomentose; Mojave and Sonoran deserts
→ 5
4. Inflorescence branches mostly slender, smooth, not ridged, not spinose; inflorescences 3-15(-23) × 5-20 cm; subshrubs or shrubs, 3-7 × 5-12(-15) dm; Great Basin, ec California and Nevada
var. humilius
4. Inflorescence branches stoutish, faintly ridged and grooved, spinose; inflorescences 3-7(-10) × 3-10(-12) cm; shrubs, 1-3 × 1.5-5(-8) dm; Mojave Desert, sw Utah and nw Arizona
var. subspinosum
5. Inflorescence branches thinly tomentose to floccose; s California, s Nevada, nw Arizona
var. floccosum
5. Inflorescence branches glabrous; s Nevada, California
→ 6
6. Involucres racemosely arranged; inflorescence branches whiplike; s Nevada
var. clokeyi
6. Involucres racemosely arranged only distally; inflorescence branches not whiplike; California
→ 7
7. Leaf blades 0.5-1.5 cm, glabrous abaxially; inflorescence branches stout; sc California
var. heermannii
7. Leaf blades 1.5-3(-4) cm, mostly tomentose to floccose abaxially (at least in early anthesis); inflorescence branches slender; sw California
var. occidentale
Source FNA vol. 5, p. 304. FNA vol. 5, p. 356.
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. 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
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. 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. heermannii var. argense, E. heermannii var. clokeyi, E. heermannii var. floccosum, E. heermannii var. heermannii, E. heermannii var. humilius, E. heermannii var. occidentale, E. heermannii var. subspinosum, E. heermannii var. sulcatum
Synonyms E. geniculatum E. ursinum var. siskiyouense
Name authority Durand & Hilgard: in War Department [U.S.], Pacif. Railr. Rep. 5(3): 14. (1857) Small: Bull. Torrey Bot. Club 25: 44. (1898)
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