Flora of North America species comparison

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Eriogonum umbellatum

Polygonaceae subfam. eriogonoideae

sulfur buckwheat, sulfurflower, sulphur buckwheat, sulphur flower, sulphur-flower buckwheat, sulphur-flower wild buckwheat

wild buckwheat
Habit Herbs, subshrubs, or shrubs, cespitose, matted or spreading, sometimes erect, often polygamo-dioecious, (0.2–)1–12(–20) × (0.5–)1–12(–20) dm, glabrous or tomentose. Shrubs, subshrubs, or herbs, sometimes nearly arborescent (Eriogonum), perennial, biennial, or annual, homophyllous, polycarpic (rarely monocarpic in Eriogonum); taproot solid or, rarely, chambered (Eriogonum), slender to stout.
Stems

caudex spreading;

aerial flowering stems spreading to erect or nearly so, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, nonflowering aerial branches, (0.1–)0.5–3(–4) dm, without a whorl of bracts at midlength.

prostrate or decumbent to spreading or erect, sometimes scapose, rarely absent (Eriogonum), without recurved spines, glabrous or pubescent, sometimes glandular;

nodes not swollen;

tendrils absent;

caudex stems tightly compact to spreading and at or just below the soil surface or spreading to erect and above the soil surface, woody;

aerial flowering stems decumbent to spreading or erect, arising at nodes of caudex branches, at distal nodes of aerial branches, or directly from the root, slender to stout and solid or slightly to distinctly fistulose, rarely disarticulating in ringlike segments (Eriogonum).
Leaves

in loose to compact basal rosettes;

petiole 0.1–3(–4) cm, mostly tomentose to floccose or glabrous;

blade oblong-ovate or oblanceolate to elliptic to oval, 0.3–3(–4) × 0.1–2.5 cm, densely lanate to tomentose or floccose abaxially, tomentose to floccose or glabrous adaxially, occasionally glabrous on both surfaces, margins entire, plane or rarely wavy.

deciduous (persistent in some shrubby and matted Eriogonum species), basal or basal and cauline, rarely only cauline, rosulate, alternate, or infrequently opposite (Goodmania) or in whorls of 3 (Gilmania);

stipules absent (possibly vestigial in some perennial species of Chorizanthe);

petiole present, sometimes indistinct, not articulate or with extrafloral nectaries;

blade simple, rarely lobed (Pterostegia), rarely awn-tipped (Goodmania).
Inflorescences

umbellate or compound-umbellate, rarely subcapitate or capitate, 3–25 × 2–18 cm;

branches tomentose to floccose or glabrous, rarely with whorl of bracts ca. midlength;

bracts 3–several, semileaflike at proximal node, 0.3–2.5 × 0.2–1.8 cm, usually scalelike distally, 1–5 × 0.5–3 mm.

terminal or terminal and axillary, cymose and dichotomously or trichotomously branched, or racemose, simple or compound umbellate, or capitate;

bracts usually connate proximally, leaflike or scalelike, entire apically, sometimes awn-tipped, glabrous or pubescent.
Peduncles

absent or erect to deflexed relative to inflorescence branch, sometimes reflexed, straight or curved.
Involucres

1 per node, turbinate to campanulate, 1–6 × (1–)1.5–10 mm, tomentose to thinly floccose or glabrous;

teeth 6–12, lobelike, reflexed, 1–4(–6) mm.

Flowers

2–10(–12) mm, including (0.7–)1.3–2 mm stipelike base;

perianth various shades of white, yellow, or red, glabrous;

tepals monomorphic, usually spatulate to obovate;

stamens exserted, 2–8 mm;

filaments pilose proximally.

(1–)2–30(–100) per involucral structure, occasionally with stipelike base distal to articulations (Eriogonum);

perianth accrescent in fruit, mostly white to red, yellow, light green, greenish white, maroon, or purple, urceolate to campanulate, occasionally glandular or pustulose abaxially, nearly always minutely glandular along midvein adaxially, glabrous or pubescent;

tepals (5–)6, in 2 whorls of 3, connate proximally, typically not forming tube (except Chorizanthe, Lastarriaea, Mucronea, Pterostegia), petaloid or, rarely, coriaceous (Lastarriaea), monomorphic or dimorphic, entire, emarginate, or lobed to laciniate apically, rarely awn-tipped (Lastarriaea) or apiculate (Eriogonum);

nectary a disk at base of ovary;

stamens 3, 6, or 9 (variously 3–9 in Chorizanthe, Mucronea);

staminodes absent;

filaments usually distinct, occasionally forming staminal tube (Chorizanthe);

pistils 3-carpellate, homostylous;

ovary 1-locular;

ovule 1, orthotropous, placentation basal;

styles 3, distinct;

stigmas capitate.
Achenes

light brown to brown, 2–7 mm, glabrous except for sparsely pubescent beak.

brown to black or maroon, homocarpic, winged or unwinged, 3-gonous, less often lenticular or globose-lenticular to globose.
Seeds

embryo straight or curved.
Involucral

structures tubular (involucre) or consisting of a series of individual bractlike lobes (involucral bracts) arranged in whorls or spirals, rarely absent (Gilmania), awns present or absent;

involucre cylindric, prismatic, turbinate, campanulate, urceolate, or funnelform with 3–8(–36) usually erect teeth or 4–12 spreading to reflexed lobes (teeth and lobes are distal portions of proximally connate involucral bracts);

involucral bracts in 1–3 whorls, rarely in spirals (Johanneshowellia), free or connate only at base, linear to oblanceolate or ovate.

Eriogonum umbellatum

Polygonaceae subfam. eriogonoideae
Distribution
from FNA
AZ; CA; CO; ID; MT; NV; OR; UT; WA; WY; AB; BC
[WildflowerSearch map]
[BONAP county map]
Mainly temperate regions of w North America (Alaska to Mexico); uncommon in South America (Argentina and Chile) and e North America (WVa s to c Fla, e to Mo, Okla, and Tex)
Discussion

Varieties 41 (41 in the flora).

Eriogonum umbellatum is a widespread and exceedingly variable species rivaling Astragalus lentiginosus Douglas ex Hooker in complexity. Only the variety majus is sometimes recognized at the species rank (as E. subalpinum).

In the following key and descriptions, reference is made to “glabrous” leaf surfaces. This is a function of both age and power of observation. High-power magnification may show some exceedingly fine hairs that are not readily observable to the naked eye. Furthermore, new leaves that ultimately will be “glabrous” will have some fine-tomentose pubescence that becomes less obvious (or even wholly inconspicuous) as the blade expands and matures. Here, the term “glabrous” is used to refer to leaves that are not obviously hairy and are typically bright green on both surfaces when the plant is at full anthesis.

There are several reported uses of sulphur flower in the enthobotany literature, mostly without an indication of the variety. J. B. Romero (1954) indicated that in California, where most of the variants are found, an infusion of the flowers is used for ptomaine poisoning, and M. L. Zigmond (1981) stated that the Kawaiisu used mashed flowers as a salve for gonorrheal sores. E. V. A. Murphey (1959), who worked with P. Train et al. (1941), reported that in Nevada members of the species (most likely var. nevadense) were used in the treatment of colds and stomachaches; J. H. Steward (1933) reported the same uses among the Owens Valley Piute in California. Train and his group noted that poultices of leaves and sometimes roots were used for lameness or rheumatism. In Oregon, leaves of var. ellipticum were used in a poultice to soothe pain, especially that resulting from burns (F. V. Coville 1897; L. Spier 1930). Most of the reports associated with the Navajo or Diné people probably relate to the use of var. subaridum. L. C. Wyman and S. K. Harris (1951) found the species used as a disinfectant or an emetic. The Cheyenne people employed a mixture of powdered stems and flowers to halt lengthy menses (G. B. Grinnell 1923; J. A. Hart 1981). According to A. Johnston (1987), the Blackfoot made a tea from boiled leaves.

The cythera metalmark butterfly (Apodemia mormo cythera) is found in association with a few varieties of sulphur flower (G. F. Pratt and G. R. Ballmer 1991). More commonly seen with the species are the Rocky Mountain dotted-blue (Euphilotes ancilla) and lupine blue (Plebeius lupini).

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

Genera 20, species ca. 325 (19 genera, 281 species in the flora).

Detailed habitat, elevation, and distribution data for the eriogonoid genera are maintained by the author and available on the Web at: “Eriogonoideae (Polygonaceae) of North America north of Mexico” (http://www.life.umd.edu/emeritus/reveal/pbio/eriog/key.html).

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Key
1. Inflorescences compound-umbellate, or with at least some branches seemingly with whorl of bracts about midlength
→ 2
1. Inflorescences umbellate, not compound-umbellate or with any branches seemingly with whorl of bracts about midlength
→ 22
2. Inflorescence branches with a whorl of bracts at midlength (see also E. umbellatum var. polyanthum)
→ 3
2. Inflorescence branches without a whorl of bracts at midlength, bracts restricted to base of inflorescence or involucres
→ 4
3. Perianths bright yellow; flowers 7-10 mm; Sierra Nevada, c California
var. torreyanum
3. Perianths cream or whitish; flowers 4-7 mm; Warner Mountains, se Oregon and ne California
var. glaberrimum
4. Flowers 7-10(-12) mm; shrubs 5-15(-20) × 5-20 dm; inflorescences branched 2-4 times; Humboldt and Trinity counties, California
var. speciosum
4. Flowers 3-8 mm; matted herbs or subshrubs, or, if shrubby, inflorescences branched 4 or more times, or not of Humboldt and Trinity counties, California
→ 5
5. Perianths cream, whitish, or pale yellow to greenish yellow, becoming reddish brown to rose or pink
→ 6
5. Perianths bright yellow, not becoming reddish brown to rose or pink
→ 7
6. Perianths yellow, becoming reddish brown to rose or pink, with large reddish spot on each midrib; plants spreading to somewhat prostrate mats; se California, s Nevada
var. versicolor
6. Perianths cream, whitish, or pale yellow to greenish yellow, without large reddish spot on midrib; plants subshrubs or shrubs; nc Arizona, se California, s Nevada, s Utah
var. juniporinum
7. Leaf blades thinly floccose, glabrous, or densely lanate to tomentose on both surfaces at anthesis (see also E. umbellatum var. munzii, s California)
→ 8
7. Leaf blades thinly to densely tomentose or lanate abaxially, less so to floccose, nearly glabrous, or glabrous adaxially (rarely both surfaces tomentose in E. umbellatum var. munzii, s California)
→ 13
8. Leaf blades densely lanate on both surfaces; wc California
var. bahiiforme
8. Leaf blades lanate to tomentose abaxially, tomentose to densely floccose adaxially, sometimes thinly floccose or glabrous on both surfaces; nw or ec California, Intermountain West, or Pacific Northwest.
→ 9
9. Leaf blades lanate to tomentose abaxially, thinly tomentose to floccose and greenish adaxially; nw California
→ 10
9. Leaf blades usually thinly floccose or glabrous on both surfaces; not of nw California
→ 11
10. Leaf blades 0.3-0.7 cm wide; involucral lobes 1-3 mm; plants of serpentine soils; Glenn, Lake, Mendocino, Sonoma, Tehama, and Trinity counties, California
var. smallianum
10. Leaf blades (0.5-)0.8-1.8(-2) cm wide; involucral lobes (3-)4-6 mm; plants of nonserpentine soils; Siskiyou County,California
var. lautum
11. Leaf blades thinly floccose on both surfaces, or glabrous and green adaxially (rarely glabrous on both surfaces in s Utah, or tomentose abaxially in se Utah); e and s California to sw Colorado and ne Arizona
var. subaridum
11. Leaf blades glabrous on both surfaces; e Idaho, ne Oregon, se Washington, and ec California
→ 12
12. Herbs; leaf blades broadly elliptic, 1-1.5 cm wide; e Idaho, ne Oregon, and se Washington
var. devestivum
12. Subshrubs or shrubs; leaf blades oblanceolate to narrowly elliptic, 0.3-1 cm wide; s Mono, Inyo, and ne Tulare counties, California
var. chlorothamnus
13. Plants densely branched, shrubs; w foothills, Sierra Nevada, n California
→ 14
13. Plants usually matted herbs or more openly and sparsely branched subshrubs or shrubs; mountains, Sierra Nevada, c and n California, wc Nevada, or Siskiyou and Trinity mountains, nw California (but not on the western foothills), sw Oregon, n Arizona, Colorado, Idaho, Montana, or Washington
→ 15
14. Leaf blades white-tomentose abaxially; inflorescences branched 1-2(-3) times, branches thinly floccose or glabrous, central branch sometimes seemingly with a whorl of bracts ca. midlength; Butte, Plumas, and Sierra counties
var. polyanthum
14. Leaf blades rusty-lanate to tomentose abaxially; inflorescences branched 3-4 time, branches tomentose to floccose, central branch without a whorl of bracts ca. midlength; Butte County
var. ahartii
15. Flowering stems mostly sparsely floccose or glabrous.
→ 16
15. Flowering stems usually tomentose or floccose, rarely nearly glabrous at maturity
→ 18
16. Leaf blades usually narrowly elliptic, 0.3-1(-1.3) cm wide; plants subshrubs or spreading mats; California, Nevada, Oregon
→ 17
16. Leaf blades oblong-ovate to elliptic or oval, 1-1.5(-2) cm wide; plants compact mats; n Arizona
var. cognatum
17. Leaf margins plane; flowering stems without a single leaflike bract ca. midlength; Sierra Nevada, e California, wc Nevada
var. furcosum
17. Leaf margins often finely wavy; flowering stems often with a single leaflike bract ca. midlength; Siskiyou and Trinity mountains, nw California, sw Oregon
var. argus
18. Leaf blades usually broadly elliptic to oval
→ 19
18. Leaf blades elliptic
→ 20
19. Leaf blades gray abaxially; c Colorado
var. ramulosum
19. Leaf blades white abaxially; n California
var. lautum
20. Leaf blades 1-1.5 cm wide, usually glabrous adaxially; Idaho, w Montana, Oregon, and e Washington
var. ellipticum
20. Leaf blades 0.3-1 cm wide, usually floccose adaxially; California
→ 21
21. Leaf blades 0.3-0.7 cm wide; nw California
var. smallianum
21. Leaf blades 0.5-1 cm wide; s California
var. munzii
22. Perianths usually whitish or cream to red, occasionally yellow
→ 23
22. Perianths bright yellow (pale yellow in some individuals of var. vernum in Nevada)
→ 27
23. Leaf blades densely lanate on both surfaces; perianths lemon yellow to yellowish red; San Gabriel and San Bernardino mountains, e Los Angeles and w San Bernardino counties, California
var. minus
23. Leaf blades tomentose to floccose or glabrous adaxially, sometimes glabrous on both surfaces at full anthesis; perianths not lemon yellow or yellowish red; not of e Los Angeles or w San Bernardino counties, California
→ 24
24. Leaf blades glabrous on both surfaces; s Idaho and sw Montana to w Wyoming, ne Nevada, and n Utah
var. desereticum
24. Leaf blades densely floccose to tomentose or lanate at least abaxially at full anthesis; widespread.
→ 25
25. Leaf blades densely lanate abaxially, glabrous and olive green to bright green adaxially; plants compact mats; perianths cream; Rocky Mountains to Cascade Range
var. majus
25. Leaf blades densely floccose to tomentose abaxially, less so or glabrous and green adaxially; plants spreading mats, rarely compact; perianths pale yellow to cream or whitish, rarely greenish white or yellow, becoming reddish brown to rose or pink, with large reddish spots on each midrib; Rocky Mountains to Sierra Nevada.
E. umbellatumvar. dichrocephalum
26. Perianths pale yellow to cream or whitish, rarely greenish white; leaf blades usually greenish adaxially; se Oregon and e California to w Montana, s Idaho, w Wyoming, c Nevada, and n Utah
var. dichrocephalum
26. Perianths yellow, becoming reddish brown to rose or pink, with large reddish spot on each midrib; leaf blades usually reddish adaxially; se California, s Nevada
var. versicolor
27. Umbels with branches usually longer than 2.5 cm.
→ 28
27. Umbels with branches usually shorter than 2.5 cm (immature specimens should be keyed through the opposing couplet as well)
→ 36
28. Leaf blades glabrous on both surfaces at full anthesis, occasionally with some individual blades thinly floccose abaxially
var. aureum
28. Leaf blades at least thinly tomentose or lanate abaxially
→ 29
29. Leaf blades thinly tomentose to thinly floccose on both surfaces, or glabrous adaxially
→ 30
29. Leaf blades densely white-lanate or tomentose abaxially, less so to floccose or glabrous adaxially
→ 33
30. Plants matted herbs
→ 31
30. Plants subshrubs or shrubs
→ 32
31. Leaf blades broadly elliptic to ovate, (0.8-)2-3(-3.5) × (0.7-)1-2(-2.5) cm; s Idaho, ne Nevada, wc Wyoming
var. stragulum
31. Leaf blades narrowly elliptic, 0.7-2.5 × 0.3-1 cm; nw Arizona
var. mohavense
32. Flowers 4-7 mm; Cali-fornia, n Nevada, se Oregon
var. nevadense
32. Flowers (5-)6-10 mm; n Nye County, Nevada
var. vernum
33. Subshrubs 3-5 dm; non-serpentine soils; n California and sc Oregon
var. dumosum
33. Herbs (0.7-)1-4.5(-5) dm; Rocky Mountains or, if in California and Oregon, often on serpentine soils
→ 34
34. Plants usually compact mats; nonserpentine soils; Rocky Mountains, sw Montana and e Idaho to Colorado, s and w Wyo-ming, and n Utah
var. umbellatum
34. Plants spreading to prostrate mats; often on serpentine soils; n California and sw Oregon.
→ 35
35. Flowering stems 1-2.5(-4) dm; leaf blades 0.5-2(-3.5) cm; flowers 6-8(-9) mm; 400-1700(-2100) m
var. goodmanii
35. Flowering stems 0.5-1.5 dm; leaf blades 0.5-1(-1.5) cm; flowers 3-6 mm; 1700-2800 m
var. humistratum
36. Plants prostrate, mostly in montane to subalpine or alpine communities.
→ 37
36. Plants erect to slightly spreading, not prostrate, usually not in subalpine or alpine communities
→ 39
37. Leaf blades glabrous on both surfaces at full anthesis
var. porteri
37. Leaf blades tomentose at least abaxially at full anthesis
→ 38
38. Leaf blades narrowly elliptic, 0.3-0.6(-1) × 0.2-0.4(-0.6) cm, tomentose abaxially, slightly less so and greenish adaxially; s Sierra Nevada and White Mountains, Mono, Inyo, and Tulare counties, California
var. covillei
38. Leaf blades broadly elliptic, 0.5-1.5(-2.5) × 0.5-1.2(-1.5) cm, tomentose or glabrous and olive green adaxially; n Cascade Range, Benton, Clackamas, Hood River, and Wasco counties, Oregon, and Kittitas and Yakima counties, Washington
var. haussknechtii
39. Leaf blades glabrous on both surfaces, sometimes with marginal hairs at full anthesis
→ 40
39. Leaf blades lanate to tomentose or floccose at least abaxially at full anthesis.
→ 41
40. Leaf blades without marginal hairs; se Oregon, Idaho, and Nevada to w Montana, Wyoming, Colorado, and Utah
var. aureum
40. Leaf blades with marginal hairs; Cascade Range, Washington
var. hypoleium
41. Leaf blades thinly tomentose abaxially, less so to floccose or glabrous and green adaxially; Sierra Nevada and Great Basin ranges
var. nevadense
41. Leaf blades densely lanate to tomentose abaxially; widespread, generally not in Great Basin ranges.
→ 42
42. Mature leaf blades lanate to tomentose on both surfaces; Yellowstone National Park, Wyoming
var. cladophorum
42. Mature leaf blades densely lanate or tomentose abaxially, less so to floccose or glabrous and greenish adaxially; w United States
→ 43
43. Larger leaf blades usually 0.3-1.5(-2) cm, usually elliptic to oblong; plants subshrubs or herbs
→ 44
43. Larger leaf blades 1-3(-3.5) cm, elliptic to ovate; plants subshrubs, or compact or spreading mats
→ 45
44. Leaf blades usually elliptic; non-serpentine soils; ne California, se Oregon, sw Idaho, n Nevada
var. modocense
44. Leaf blades elliptic to oblong; serpentine outcrops; nw California 107aa. Eriogonum umbellatum var. nelsoniorum
→ 43
45. Plants subshrubs; n Cascade Range, Washington
var. sandbergii
45. Plants compact or spreading mats; Rocky Mountains, Sierra Nevada, Transverse, and Argus ranges, California, Colorado, Idaho, Montana, Utah, and Wyoming
→ 46
46. Leaf blades elliptic to ovate, densely white-lanate abaxially; Rocky Mountains, sw Montana and e Idaho to s Colorado, w and s Wyoming, and s Utah
var. umbellatum
46. Leaf blades elliptic, densely grayish-lanate abaxially; s Sierra Nevada, Transverse Ranges, and Argus Range, California
var. canifolium
1. Plants annual with involucre forming distinct tube, this cylindric or prismatic and awn-tipped typically with at least some awns uncinate or curved, rarely turbinate or urceolate to campanulate and then with 5 divergent, straight awns, or reduced to 1-4, often awn-tipped involucral bracts; flowers mostly 1-2(-6) per involucre
→ 2
1. Plants perennial or biennial, or, if annual, with involucre forming distinct tube, this turbinate to campanulate or hemispheric and awnless or tipped with erect, straight awns or reduced to awnless involucral bracts, absent entirely in Gilmania; flowers mostly (2-)6-200 per involucre (Eriogoneae, Eriogonineae)
→ 10
2. Involucres reduced to 1 highly modified, 2-winged bract; leaf blades entire or variously lobed; stems sprawling and spreading (Pterostegieae)
Pterostegia
2. Involucres tubular or reduced to 3(-4) bracts; leaf blades entire; stems erect to prostrate
→ 3
3. Involucres reduced to 3(-4) bracts; tepals mucronate or awn-tipped; California
→ 4
3. Involucres tubular; tepals not mucronate or awn-tipped (Chorizanthineae); widespread
→ 5
4. Perianths yellowish, densely tomentose abaxially; tepals mucronate apically; stamens 6 or 9; inflorescence branches tomentose (Hollisteriineae)
Hollisteria
4. Perianths light green to greenish white, thinly pubescent abaxially; tepals acute or awn-tipped apically; stamens 3; inflorescence branches thinly pubescent (Chorizanthineae)
Lastarriaea
5. Inflorescence bracts opposite, mostly 2, sometimes numerous and whorled; flowers 1(-2) per involucre; w North America
Chorizanthe
5. Inflorescence bracts alternate and positioned on one side of branch or perfoliate around branch, 3-lobed or parted; flowers (1-)2-6 per involucre; widespread
→ 6
6. Involucres 5-toothed, each terminated by divergent awn; flowers 4(-6) per involucre; perianth pubescent abaxially; wc California
Aristocapsa
6. Involucres 2-4(6)-lobed or -toothed, or, if 5-awned apically, involucre with additional basal awns; flowers (1-)2-3 per involucre, perianth glabrous by densely papillate or pubescent abaxially; California
→ 7
7. Involucres not awned basally; California
→ 8
7. Involucres awned basally; sw North America
→ 9
8. Perianths pubescent abaxially; flowers bisexual
Mucronea
8. Perianths glabrous, densely papillate abaxially; flowers bisexual and unisexual, with proximal 1 pistillate and distal 1 bisexual
Systenotheca
9. Basal awns 3, on saccate lobes; terminal awns 5, straight, involucres 3-angled; flowers 2 per involucre; sw North America
Centrostegia
9. Basal awns 6, on nonsaccate basal lobes; terminal awns 6, uncinate; involucres 6-angled; flowers 3 per involucre; sw California
Dodecahema
10. Plants perennial, if annual or biennial involucre tubular and awnless
→ 11
10. Plants annual; involucres tubular and awn-tipped or series of free or basally connate, awnless bracts, rarely absent (Gilmania)
→ 12
11. Involucres tubular, the lobes rarely connate proximally; plants annual, biennial, or perennial; widespread
Eriogonum
11. Involucres reduced to series of 2-5 obscure, awnless bracts; plants perennial shrubs; ec California
Dedeckera
12. Involucres not awned or absent
→ 13
12. Involucres awn-tipped
→ 16
13. Involucral bracts in 2 whorls of 3; sw Wyoming to ne Arizona and nw New Mexico
Stenogonum
13. Involucral bracts absent or in 1 whorl or tight spiral; California, Nevada, sw Utah
→ 14
14. Stamens 3; s California, sw Arizona
Nemacaulis
14. Stamens 9; se California, s Nevada, sw Utah
→ 15
15. Perianths thinly pubescent abaxially; involucral bracts absent; Death Valley, California
Gilmania
15. Perianths glabrous, smooth or minutely pustulose; involucral bracts (3-)4(-7); se California, s Nevada, sw Utah
Johanneshowellia
16. Involucres not tubular; se California, ec Nevada
Goodmania
16. Involucres tubular; widespread. [17. Shifted to left margin.—Ed.]
→ 17
17. Involucral awns 5(-6); tepals 3-lobed or laciniate apically; achenes 3-gonous; s California
Sidotheca
17. Involucral awns either (3-)4 or 7-36; tepals mostly entire, rarely irregularly divided or retuse apically; achenes globose-lenticular; widespread
→ 18
18. Involucral awns (3-)4; leaf blades linear to spatulate, margins entire; se Washington e to sw Wyoming and s to Mexico
Oxytheca
18. Involucral awns 7 or more, rarely 4; leaf blades broadly obovate or spatulate to oblong or oblanceolate, margins ciliate-denticulate; s California
Acanthoscyphus
Source FNA vol. 5, p. 335. FNA vol. 5, p. 218. Author: James L. Reveal.
Parent taxa Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Oligogonum Polygonaceae
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. thymoides, E. tiehmii, E. tomentosum, E. trichopes, E. tripodum, E. truncatum, E. tumulosum, E. twisselmannii, 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. umbellatum var. ahartii, E. umbellatum var. argus, E. umbellatum var. aureum, E. umbellatum var. bahiiforme, E. umbellatum var. canifolium, E. umbellatum var. chlorothamnus, E. umbellatum var. cladophorum, E. umbellatum var. cognatum, E. umbellatum var. covillei, E. umbellatum var. desereticum, E. umbellatum var. devestivum, E. umbellatum var. dichrocephalum, E. umbellatum var. dumosum, E. umbellatum var. ellipticum, E. umbellatum var. furcosum, E. umbellatum var. glaberrimum, E. umbellatum var. goodmanii, E. umbellatum var. haussknechtii, E. umbellatum var. humistratum, E. umbellatum var. hypoleium, E. umbellatum var. juniporinum, E. umbellatum var. lautum, E. umbellatum var. majus, E. umbellatum var. minus, E. umbellatum var. modocense, E. umbellatum var. mohavense, E. umbellatum var. munzii, E. umbellatum var. nevadense, E. umbellatum var. polyanthum, E. umbellatum var. porteri, E. umbellatum var. ramulosum, E. umbellatum var. sandbergii, E. umbellatum var. smallianum, E. umbellatum var. speciosum, E. umbellatum var. stragulum, E. umbellatum var. subaridum, E. umbellatum var. torreyanum, E. umbellatum var. umbellatum, E. umbellatum var. vernum, E. umbellatum var. versicolor, E. umbellatumvar. dichrocephalum
Acanthoscyphus, Aristocapsa, Centrostegia, Chorizanthe, Dedeckera, Dodecahema, Eriogonum, Gilmania, Goodmania, Hollisteria, Johanneshowellia, Lastarriaea, Mucronea, Nemacaulis, Oxytheca, Pterostegia, Sidotheca, Stenogonum, Systenotheca
Name authority Torrey: Ann. Lyceum Nat. Hist. New York 2: 241. (1827) Arnott: in M. Napier, Encycl. Brit. ed. 7, 5: 126. (1832)
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).



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