Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Eriogonum heermannii

Eriogonum rixfordii

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

pagoda buckwheat, pagoda wild buckwheat, Rixford's 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, erect, annual, (1.5–)2–4 dm, glabrous, greenish to grayish.
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 absent;

aerial flowering stems erect, solid, not fistulose, 0.3–2 dm, glabrous.
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.

basal;

petiole 1–3(–5) cm, floccose;

blade cordate to orbiculate, (0.5–)1–3 × (0.5–)1–3 cm, densely white-tomentose abaxially, less so to subglabrous and grayish to greenish adaxially, margins entire.
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.

cymose, diffuse, of many horizontal tiers of flat-topped branches, 10–35 × 5–35 cm;

branches glabrous;

bracts 3, scalelike, 1–3 × 0.5–1.5 mm.
Peduncles

absent.

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.

deflexed, narrowly campanulate, 1–1.5 × 1.5–2 mm, glabrous;

teeth 5, erect, 0.4–0.7 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.

1.3–1.5 mm;

perianth white with greenish midribs, becoming reddish, glabrous;

tepals dimorphic, those of outer whorl narrowly oval to cordate, those of inner whorl narrowly lanceolate;

stamens included, 1–1.3 mm;

filaments glabrous.
Achenes

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

dark brown, lenticular, 1.3–1.5 mm, glabrous.
2n

= 40.

Eriogonum heermannii

Eriogonum rixfordii
Phenology Flowering Jun–Dec.
Habitat Sandy to gravelly washes and slopes, saltbush communities
Elevation (30-)100-1600 m ((100-)300-5200 ft)
Distribution
from FNA
AZ; CA; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV
[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.)

Of conservation concern.

Eriogonum rixfordii is occasional in the Death Valley area of Inyo County, California, and adjacent southwestern Nye County, Nevada. Its habit is so striking that it is often collected as a novelty. It is rarely common and never weedy.

(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. 396.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma
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. 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. 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. deflexum subsp. rixfordii
Name authority Durand & Hilgard: in War Department [U.S.], Pacif. Railr. Rep. 5(3): 14. (1857) S. Stokes: Leafl. W. Bot. 1: 29. (1932)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Fabaceae, Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers