Eriogonum strictum |
Eriogonum exaltatum |
|||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Blue Mountain buckwheat, strict buckwheat |
ladder buckwheat, ladder wild buckwheat |
|||||||||||||
Habit | Herbs, erect, loosely to densely matted, not scapose, 1–5 × 1–10 dm, tomentose or glabrous. | Herbs, erect, annual, (0.5–)3–6(–10) dm, glabrous, glaucous, grayish. | ||||||||||||
Stems | spreading to erect, with or without persistent leaf bases, up to 1/4 height of plant; caudex stems absent or spreading to matted; aerial flowering stems erect to spreading, slender, solid, not fistulose, 1–3 dm, tomentose or glabrous. |
caudex absent; aerial flowering stems erect, solid, not fistulose, (0.5–)1–2 dm, glabrous. |
||||||||||||
Leaves | basal, 1 per node; petiole rarely twisted or curled, 1–6 cm, mostly tomentose; blade elliptic to ovate, 0.5–2.5(–4) × (0.3–)0.5–1.5 cm, lanate, tomentose to floccose on both surfaces, sometimes sparsely tomentose to floccose and greenish or floccose to subglabrous or glabrous adaxially, margins plane. |
basal; petiole 1–10 cm, tomentose; blade sub-cordate to orbiculate, (1.5–)2–5(–8) × (1.5–)2–5(–8) cm, densely white-tomentose abaxially, floccose to subglabrous and green adaxially, margins often wavy. |
||||||||||||
Inflorescences | umbellate-cymose to cymose, 1–20 × 3–25 cm; branches dichotomous, tomentose to floccose or less often glabrous; bracts 3, scalelike, triangular, 1–3 mm. |
cymose, spreading when immature, quickly becoming narrowly erect and strict with whiplike branches, (5–)10–50(–80) × 10–50 cm; branches glabrous, glaucous; bracts 3, scalelike, 1–1.5(–2) × 0.4–1 mm. |
||||||||||||
Peduncles | absent. |
absent or erect, straight, slender, 0.1–0.2 cm, glabrous. |
||||||||||||
Involucres | 1 per node, rarely 2–5 per cluster, narrowly turbinate to turbinate-campanulate, 4–6 × 1.5–5 mm, tomentose or glabrous; teeth 5, erect, 0.5–1.3 mm. |
turbinate, 2–2.5(–3) × 1.5–2.5 mm, glabrous; teeth 5, erect, 0.5–1.5 mm. |
||||||||||||
Flowers | 3–5(–6) mm; perianth yellow or white to rose or purple, glabrous; tepals connate proximally, dimorphic, those of outer whorl elliptic to nearly orbiculate, 2–3 × 2–3 mm, those of inner whorl oblanceolate to oblong, 3–4 × 1–2 mm; stamens included to slightly exserted, 2–5 mm; filaments pilose proximally. |
1.5–2 mm; perianth white with green or reddish midribs, becoming pinkish, glabrous; tepals dimorphic, those of outer whorl oblong, those of inner whorl lanceolate; stamens exserted, 1.5–2.5 mm; filaments pilose proximally. |
||||||||||||
Achenes | light brown to brown, 3–3.5 mm, glabrous. |
dark brown to blackish, 3-gonous, 2–2.5 mm, glabrous. |
||||||||||||
2n | = 40. |
|||||||||||||
Eriogonum strictum |
Eriogonum exaltatum |
|||||||||||||
Phenology | Flowering May–Oct. | |||||||||||||
Habitat | Sandy to gravelly flats and slopes, saltbush, creosote bush, greasewood, blackbrush, and mesquite communities, rarely in pinyon-juniper woodlands | |||||||||||||
Elevation | 500-1400 m (1600-4600 ft) | |||||||||||||
Distribution |
CA; ID; MT; NV; OR; WA
|
AZ; CA; NV; UT |
||||||||||||
Discussion | Varieties 4 (4 in the flora). Eriogonum strictum, E. niveum, and E. ovalifolium form a complex of closely related species differing in leaf, inflorescence branching, and flower features. Variety proliferum appears to be the basal entity of the complex, approaching both E. niveum and E. ovalifolium var. pansum in its pubescence and branching pattern. Also, specimens of var. proliferum are sometimes difficult to differentiate from E. nudum var. oblongifolium. Careful observation, though, will permit well-made collections to be easily distributed among the individual species. An alternative taxonomy is to reduce all of the taxa to E. ovalifolium and recognize a series of subspecies and varieties. It is possible that additional study will show that E. strictum is sufficiently distinct from its tomentose to floccose counterparts to justify recognition of E. proliferum. In that case, both var. anserinum and var. greenei would be assigned to the latter species. Or, one could follow C. L. Hitchcock et al. (1955–1969, vol. 2) and recognize subsp. strictum as distinct from subsp. proliferum, with the latter consisting of varieties proliferum, anserinum, and greenei. Members of the Eriogonum strictum are food plants for the Bauer’s dotted-blue butterfly (Euphilotes baueri). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eriogonum insigne has been a troublesome taxon. The type, collected by E. Palmer in 1876, is a curious specimen from near Paragonah in Iron County, Utah. That expression has not been recollected and, after another frustrating review of the type material, it is now referred to E. deflexum, along with other odd specimens from southern Nevada and California that have always been difficult to assign. As a result, the tall, upright plants with long, whiplike branches of northwestern Arizona (Mohave County), southern Nevada (northeastern Clark and southern Lincoln counties), and southwestern Utah (southwestern Washington County), are now recognized under the name E. exaltatum. Some specimens remain problematic. Immature plants of E. exaltatum (Goodding 2302, GH, MIN, MO, NY, RM, UC) resemble E. bifurcatum. Specimens from Eureka Valley (DeDecker 4741, NY) and western Pahrump Valley (Abrams 14248, DS, GH, NY) in Inyo County, California, appear to belong to E. exaltatum. Like Eriogonum exaltatum, some populations of E. deflexum var. deflexum have nearly erect involucres. The plants from the Buried Hills (Nye and Clark counties, Nevada) are particularly odd. Single plants from a few collections in Kane County, Utah, have sessile, seemingly erect involucres in the forks of inflorescence branches. None of these plants has the characteristic long, whiplike branches of E. exaltatum, and they are not included in E. deflexum var. deflexum. The type of E. deflexum var. rectum from San Bernardino County, California (Reveal & Broome 6385, CAS, NY, US, etc.), has individual specimens with both deflexed and somewhat erect involucres, along with whiplike branches. Collections from Imperial and San Diego counties, previously associated with what is here termed E. exaltatum, are now considered specimens of E. deflexum. Clearly, more work is required to understand these species fully. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||||||||||
Key |
|
|||||||||||||
Source | FNA vol. 5, p. 317. | FNA vol. 5, p. 397. | ||||||||||||
Parent taxa | Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla | Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma | ||||||||||||
Sibling taxa | ||||||||||||||
Subordinate taxa | ||||||||||||||
Name authority | Bentham: Trans. Linn. Soc. London 17: 414. (1836) | M. E. Jones: Contr. W. Bot. 15: 61. (1929) | ||||||||||||
Web links |