Eriogonum angulosum |
Eriogonum desertorum |
|
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angle stem buckwheat, angle-stem wild buckwheat |
Great Basin desert buckwheat, Great Basin desert wild buckwheat |
|
Habit | Herbs, erect to spreading, annual, 1–5(–10) dm, tomen-tose to floccose or glabrous, usually grayish. | Herbs, matted, scapose, 0.5–1.2 × 0.7–4 dm, tomentose or floccose, grayish. |
Stems | caudex absent; aerial flowering stems erect, striated, angled, solid, not fistulose, 0.5–1 dm, tomentose to floccose. |
spreading, with persistent leaf bases, up to 1/5 height of plant; caudex stems matted; aerial flowering stems scapelike, erect, slender, solid, not fistulose, (0.2–)0.4–1 dm, tomentose or floccose. |
Leaves | basal and cauline; basal: petiole 0.5–3 cm, mostly floccose, blade oblanceolate to oblong-lanceolate, 1–4(–4.5) × (0.2–)0.5–1(–1.3) cm, tomentose abaxially, floccose or glabrate and grayish or greenish adaxially, margins crenulate; cauline sessile, blade lanceolate to oblong, 0.5–2 × 0.3–0.8 cm, similar to basal blade. |
basal, fasciculate in terminal tufts; petiole 0.3–1.5 cm, tomentose to floccose; blade oblanceolate to elliptic or, rarely, ovate, 0.4–2(–2.5) × 0.2–1 cm, densely greenish- or grayish-white-tomentose on both surfaces or densely greenish-white tomentose abaxially, margins plane. |
Inflorescences | cymose, open, 5–80 × 10–60 cm; branches striated, angled, sparsely tomentose to glabrate; bracts 3, scalelike, 1–3 × 1–3 mm. |
capitate, 0.7–1.5 cm; branches absent; bracts 3, scalelike, triangular, 1.5–2 mm. |
Peduncles | erect, straight, slender, 1–2 cm, sparsely tomentose to glabrous. |
absent. |
Involucres | turbinate-campanulate to campanulate, 1.5–2.5(–3) × 1.5–2.5(–3), sparsely puberulent; teeth 5, erect, 0.3–0.6 mm. |
4–7(–9) per cluster, turbinate to turbinate-campanulate, 2–3.5 × 2–3.5 mm, weakly rigid, floccose at least on teeth; teeth 5–8, erect. |
Flowers | 1.5–1.8 mm; perianth white to rose, without a conspicuous rose-purple spot on each outer tepal, minutely glandular-puberulent; tepals dimorphic, those of outer whorl elliptic to obovate, sometimes inflated proximally, those of inner whorl narrowly spatulate; stamens exserted, 2–3 mm; filaments pilose proximally. |
2–3.5 mm; perianth yellow, glabrous; tepals connate proximal 1/4–1/3, monomorphic, lanceolate or oblong; stamens exserted, 2–4 mm; filaments glabrous or sparsely pilose proximally. |
Achenes | light brown to brown, 3-gonous, 1–1.5 mm, glabrous. |
brown, 2–3.5 mm, glabrous or sometimes with minute bristles on beak. |
Eriogonum angulosum |
Eriogonum desertorum |
|
Phenology | Flowering year-round. | Flowering May–Aug. |
Habitat | Clayey flats and slopes, mixed grassland, saltbush, and chaparral communities, oak and conifer woodlands | Gravelly or silty to clayey flats, slopes, and ridges, often on limestone soils, mixed grassland, saltbush, and sagebrush communities, pinyon-juniper woodlands |
Elevation | 0-800 m (0-2600 ft) | 1500-3000 m (4900-9800 ft) |
Distribution |
CA
|
NV; UT |
Discussion | The name Eriogonum angulosum has been applied to all of the members of its species complex except E. gossypinum. Since the 1950s, the name consistently has been applied to plants with long, exserted stamens and strongly angled stems of the Inner Coast Ranges (Alameda and Contra Costa counties south), the western foothills of the southern Sierra Nevada (Tulare County south), and the Central Valley (San Joaquin County south). The southern edge of the range is the northern foothills of the Transverse Ranges (Ventura and Los Angeles counties). The species can be common and occasionally abundant but rarely is weedy. A mixed collection (with E. gracillimum) from Barstow, San Bernardino County (K. Brandegee s.n., May 1913, UC), and two sheets of the species from San Diego gathered by Susan Stokes apparently in 1895 (B, SD) are discounted as to location. In late fruit, the bractlets at the base of the pedicel inside the involucres of Eriogonum angulosum often elongate and broaden into oblanceolate segments that fill the involucre. As a result, the involucre appears to have several rows of teeth. This feature may be seen also in E. viridescens, but typically the involucres there appear to have only two or three rows of teeth. This feature is seen rarely in E. maculatum. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eriogonum desertorum is a low- to mid-elevation species restricted to central and eastern Elko County, Nevada, and northwestern Box Elder County, Utah. The phase represented by the type is from the valley bottoms and lower foothills, although it extends onto the eastern slope of the East Humboldt Mountains to ca. 2600 m elevation. Such plants tend to have leaf blades that are grayish-tomentose on both surfaces. At higher elevations on isolated desert ranges (Jarbidge, Independent, and Kinsley mountains, where they occur as low as 1950 m) are plants that are smaller in all aspects and tend to have elliptic (rather than oblanceolate to narrowly elliptic) leaf blades; these have been named E. lewisii. Similar plants are in the Grouse Creek Mountains of Utah. As noted above, E. brevicaule var. bannockense occurs in eastern Elko County, where it is widespread and more common than E. desertorum. It is almost always at low elevations in the valley bottoms but can occur on some of the higher, isolated peaks. The leaf blades of var. bannockense are distinctly narrower and mostly longer. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 5, p. 411. | FNA vol. 5, p. 274. |
Parent taxa | Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Ganysma | Polygonaceae > subfam. Eriogonoideae > Eriogonum > subg. Eucycla |
Sibling taxa | ||
Synonyms | E. chrysocephalum subsp. desertorum, E. brevicaule var. desertorum, E. lewisii | |
Name authority | Bentham: Trans. Linn. Soc. London 17: 406, plate 18, fig. 1. (1836) | (Maguire) R. J. Davis: Fl. Idaho, 246. (1952) |
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