Chaenactis nevii |
Chaenactis nevadensis |
|
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John Day pincushion, John Day's pincushion, Nevius' chaenactis |
Nevada dustymaiden, Sierra chaenactis, Sierra pincushion |
|
Habit | Plants 10–30 cm; proximal indument greenish to grayish, stipitate-glandular and, sometimes, sparsely arachnoid or villous. | Perennials, 2–10(–12) cm (cespitose or ± matted); proximal indument ± thinning with age, whitish, lanuginose. |
Stems | mostly 1–3; branches mainly distal. |
mostly 10–20+, decumbent to ± erect. |
Leaves | basal (withering) and cauline, 2–5 cm; largest blades ± elliptic, ± plane to 3-dimensional, not succulent, 1–2-pinnately lobed; primary lobes mostly 3–8 pairs, ± remote, ultimate lobes ± plane to involute. |
± basal, 2.5–5 cm; largest blades ovate to deltate, ± plane, (1–)2-pinnately lobed; primary lobes mostly 2–4 pairs, ± congested, ultimate lobes ± plane. |
Peduncles | 1–6 cm, distally stipitate-glandular and, sometimes, ± arachnoid to villous. |
mostly ascending to erect, (0.5–)3–11 cm. |
Involucres | ± hemispheric to campanulate. |
obconic to ± cylindric. |
Florets | corollas bright yellow, 4–6.5 mm; peripheral corollas ± erect, actinomorphic, scarcely enlarged. |
|
Corollas | 5.5–8 mm. |
|
Phyllaries | longest 6–9 mm; outer predominantly stipitate-glandular and, sometimes, ± arachnoid to villous in fruit, apices ± erect, acute, rigid. |
longest 9–12(–14) mm; outer stipitate-glandular, apices erect, ± rigid. |
Heads | mostly 3–9 per stem. |
1(–2) per stem. |
Cypselae | 3.5–6 mm (compressed); pappi 0 or coroniform (of ± 10 scales, longest 0.1–0.5 mm). |
5.5–7.5 mm; pappi: longest scales 3–5 mm. |
2n | = 12. |
= 12. |
Chaenactis nevii |
Chaenactis nevadensis |
|
Phenology | Flowering late Apr–mid July. | Flowering Jul–mid Sep. |
Habitat | Nearly barren, heavy clay soils from volcanic ash and tuff, sometimes disturbed or moist sites | Loose sandy or gravelly, mainly volcanic soils or scree (rarely on serpentine), openings in or above subalpine conifer forests |
Elevation | 400–1000 m (1300–3300 ft) | 1900–3200 m (6200–10500 ft) |
Distribution |
OR
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CA; NV |
Discussion | Chaenactis nevii is known from the John Day Basin area in Gilliam, Grant, Jefferson, Wasco, and Wheeler counties. This odd and isolated species combines traits of C. artemisiifolia (sect. Acarphaea) and C. glabriuscula, and might be descended from their common ancestor. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Chaenactis nevadensis is known mainly from the northern Sierra Nevada and southern Cascade Range (Shasta to Placer counties, California; Washoe County, Nevada). It was recently discovered disjunct on ultramafic rocks of Bully Choop Mountain west of Redding, California, where it approaches small forms of C. suffrutescens in habit (see discussion there). It is sometimes cultivated in rock-gardens and may be found beyond its native range. Chaenactis nevadensis and C. suffrutescens appear to be sister or ancestor-derivative species. I have seen no evidence to support reports that C. nevadensis intergrades with C. alpigena (P. Stockwell 1940, as C. nevadensis var. mainsiana), with C. douglasii var. alpina (M. Graf 1999), or with any other taxon. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 21, p. 411. | FNA vol. 21, p. 405. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Hymenopappus nevadensis | |
Name authority | A. Gray: Proc. Amer Acad. Arts 19: 30. (1883) | (Kellogg) A. Gray: in W. H. Brewer et al., Bot. Calif. 1: 391. (1876) |
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