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

Colorado desert buckwheat, Colorado desert wild buckwheat, desert wild buckwheat

slender buckwheat, slender wild buckwheat

Habit Shrubs, erect or spreading, not scapose, 6–15(–18) × 10–20(–35) dm, white-tomentose to thinly floccose, greenish or grayish. Subshrubs or shrubs, erect to spreading, not scapose, 0.2–1.5 × (0.6–)1–13(–16) dm, white- to tannish-tomentose, floccose, or glabrous.
Stems

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

caudex stems absent or spreading in moving sand;

aerial flowering stems spreading, slender, solid, not fistulose, 1.5–4 dm, white-tomentose to thinly floccose, occasionally glabrate and light green.

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

caudex stems absent or spreading;

aerial flowering stems erect to spreading, slender, solid, not fistulose, 0.05–1.5 dm, lanate, tomentose, floccose, subglabrous, or glabrous.

Leaves

cauline, 1 per node, rarely fasciculate, quickly deciduous;

petiole (0.3–)0.5–2 cm, tomentose to floccose;

blade oblong-ovate to round-oblong or orbiculate, (0.3–)0.5–1.5(–3.5) × (0.5–)0.7–1.7(–2) cm, white-tomentose on both surfaces, margins plane, sometimes crisped.

cauline, 1 per node or fasciculate;

petiole 0.1–0.5 cm, tomentose to floccose or glabrous;

blade usually elliptic, sometimes linear to obovate, 0.3–3.5 × (0.07–)0.1–1.2 cm, tomentose abaxially, less so or glabrous adaxially, margins occasionally revolute.

Inflorescences

cymose, open, 15–90 × 20–100 cm;

branches dichotomous, white-tomentose to thinly floccose, becoming floccose or glabrate and green;

bracts 3, triangular, 0.5–1.5 mm.

cymose, compact, often flat-topped, 0.5–6(–12) × 1–10(–13) cm;

branches dichotomous, whitish-lanate to brownish- or reddish-tomentose to floccose or glabrate, infrequently green or gray and subglabrous or glabrous;

bracts 3, scalelike, linear to triangular, 1–5 mm.

Peduncles

absent or erect, slender, 0.1–0.5 cm, floccose to glabrate.

absent or mostly erect, slender, 0.3–1.5 cm, tomentose to floccose.

Involucres

1 per node, turbinate-campanulate, 1.5–2.5(–3) × 1.3–1.6(–2) mm, thinly tomentose;

teeth 4, erect, 0.3–0.5 mm.

1 per node, turbinate, (1.5–)2–3.5(–4) × 1.3–2.5(–3) mm, tomentose, floccose, subglabrous, or glabrous;

teeth 5, erect, (0.3–)0.5–1(–1.7) mm.

Flowers

(2.5–)3–4(–4.5) mm;

perianth greenish yellow to yellow, silky-villous abaxially;

tepals connate proximally, monomorphic, oblong to oblong-obovate;

stamens exserted, 2.5–4 mm;

filaments pilose proximally.

1.5–3(–4) mm;

perianth yellow or white to pink, orange, rose, red, or occasionally cream, glabrous;

tepals connate proximal 1/5–2/5, essentially monomorphic, oblong to obovate;

stamens usually exserted, 2.5–4 mm;

filaments sparsely to densely puberulent proximally.

Achenes

brown, 3–4(–4.5) mm, glabrous except for scabrellous beak.

brown, 1.5–3 mm, glabrous.

Eriogonum deserticola

Eriogonum microthecum

Phenology Flowering Jul–Jan.
Habitat Deep moving sand dunes and sandy flats, desert scrub communities
Elevation -60-200 m (-200-700 ft)
Distribution
from FNA
AZ; CA; Mexico (Baja California, Sonora)
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Eriogonum deserticola is found primarily in the moving sand dunes in the southern Salton Sea basin of extreme eastern San Diego and Imperial counties, California, with small populations in Yuma County, Arizona, and Baja California and Sonora, Mexico, where the species can be locally abundant. The larger plants are continually being buried and then uncovered by moving sand, revealing slender, grotesquely twisted trunks. R. S. Felger (2000) reported seeing some of the “exposed lateral roots” being up to six or more meters in length. It appears that the leaves are frequently stripped away by wind-blown sand.

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

Varieties 13 (13 in the flora).

Eriogonum microthecum is used as browse by deer and to a lesser degree by cattle and sheep. Some forms are now in cultivation. The species is reportedly used by the Piute of Nevada in the treatment of tuberculosis, lameness, rheumatism, and bladder trouble (P. Train et al. 1941). S. A. Weber and P. D. Seaman (1985) stated that A. F. Whiting found the plants being used as a tea by the Havasupai in northern Arizona. Members of E. microthecum are food plants for subspecies of the rare pallid blue butterfly (Euphilotes pallescens). Also found on this species is the cythera metalmark (Apodemia mormo cythera). Some authors have referred E. effusum to this species, even though the ranges of the two species do not overlap and intermediates are unknown.

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

Key
1. Perianths yellow
→ 2
1. Perianths various shades of white, cream, orange, pink, or red, not yellow
→ 4
2. Flowering stems and inflorescence branches usually glabrous; e Oregon and wc Idaho
var. microthecum
2. Flowering stems and inflorescence branches tomentose to floccose; se Oregon and sw Idaho s to e California and w Nevada
→ 3
3. Leaf blades (0.2-)0.3-0.6(-0.8) cm wide; flowers (1.5-)2-2.5(-3) mm; involucres 2-2.5 mm; achenes 1.5-2 mm; se Oregon and sw Idaho s to e California and w Nevada
var. ambiguum
3. Leaf blades 0.5-1.2 cm wide; flowers 2.5-3 mm; involucres 2.5-4 mm; achenes 2.5-3 mm; ne California, nw Nevada
var. schoolcraftii
4. Tomentum whitish (see also var. alpinum of the Sierra Nevada, California); flowering stems and inflorescence branches infrequently glabrous
→ 5
4. Tomentum brownish or reddish (may be white in var. alpinum), or flowering stems and inflorescence branches essentially glabrous
→ 6
5. Leaf margins not revolute; flowering inflorescence branches floccose or glabrous; northern phase of species
var. laxiflorum
5. Leaf margins revolute or nearly so; flowering inflorescence branches lanate to tomentose, or if subglabrous or glabrous, then southern phase of species
var. simpsonii
6. Plants shrubs, 3-6 dm
→ 7
6. Plants subshrubs, 0.2-1.5(-2) dm
→ 8
7. Flowering stems and inflorescence branches tomentose when young, becoming floccose at maturity; flowers 1.5-2(-2.5) mm; achenes 1.8-2 mm; Death Valley region, California
var. panamintense
7. Flowering stems and inflorescence branches lanate to tomentose at maturity; flowers 2-2.5(-3) mm; achenes 2.5-3 mm; Transverse Ranges, California
E. microthecumvar. corymbosoides
8. Leaf blades elliptic or ovate, margins not revolute; flowers (1.5-)2-3.5(-4) mm
→ 9
8. Leaf blades linear or linear-oblanceolate to narrowly elliptic, margins often revolute; flowers 1.5-2.5 mm
→ 10
9. Leaf blades 0.5-1 × (0.2-)0.3-0.5(-0.6) cm; involucres (2-)2.5-3 mm; flowers (2.5-)3-3.5(-4) mm; San Gabriel Mountains, California
var. johnstonii
9. Leaf blades 0.3-0.7(-0.8) × 0.1-0.4 cm; involucres 2.5-3.5 mm; flowers (1.5-)2-3.5 mm; desert ranges of se California, c Nevada, and Utah1f. Eriogonum microthecum var. lapidicola [8. Shifted to left margin—Ed.]
→ 8
10. Involucres 3-4 mm; perianths cream; San Bernardino Mountains, California
var. lacus-ursi
10. Involucres (1.5-)2-3 mm; perianths white, pink, red, or rose; Sierra Nevada of California, or e Nevada and w Utah
→ 11
11. Flowering stems glabrous; leaf blades sparsely floccose or glabrous adaxially; desert ranges, se Nevada
var. arceuthinum
11. Flowering stems white- to brownish-floccose to subglabrous, or reddish-tomentose to floccose; leaf blades floccose to subglabrous adaxially; California or wc Utah
→ 12
12. Tomentum white to brownish; Sierra Nevada, California
var. alpinum
12. Tomentum reddish; desert ranges, wc Utah
var. phoeniceum
Source FNA vol. 5, p. 302. FNA vol. 5, p. 242.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla 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. 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
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. 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. microthecum var. alpinum, E. microthecum var. ambiguum, E. microthecum var. arceuthinum, E. microthecum var. johnstonii, E. microthecum var. lacus-ursi, E. microthecum var. laxiflorum, E. microthecum var. microthecum, E. microthecum var. panamintense, E. microthecum var. phoeniceum, E. microthecum var. schoolcraftii, E. microthecum var. simpsonii, E. microthecumvar. corymbosoides
Name authority S. Watson: Proc. Amer. Acad. Arts 26: 125. (1891) Nuttall: Proc. Acad. Nat. Sci. Philadelphia 4: 15. (1848)
Web links