Horkelia fusca |
Horkelia fusca var. tenella |
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| dusky, horkelia, pinewoods, pinewoods horkelia, tawny horkelia |
delicate horkelia, pinewoods horkelia, tawny horkelia |
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| Stems | (0.6–)1–4(–5) dm. |
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| Basal leaves | (3–)4–20(–40) × (1–)1.5–4(–7) cm; leaflets narrowly cuneate to obovate to flabellate, 5–30(–35) × 2–20(–30) mm, 1/3 as wide to wider than long, divided into linear or oblanceolate to obovate teeth or lobes, sparsely to ± densely short-villous or hirsute, sometimes glabrate. |
green, (3–)4–18(–27) cm; leaflets 8–15 per side, cuneate to flabellate, 5–10(–15) × 2–10(–20) mm, 3/4 as wide to wider than long, divided 3/4+ to midrib into 5–15 lobes or teeth, surfaces not obscured, sparsely short-hirsute to glabrate. |
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| Cauline leaves | 1–5(or 6). |
2–4(or 5); leaflets of proximalmost 3–6 per side. |
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| Inflorescences | green to ± reddish, congested to open, comprising no more than 1/4 of stem, composed of 3–10(–20)-flowered glomerules, glandular hairs sometimes red-septate; bracts acute- to acuminate-lobed, sometimes partly obscuring pedicels and flowers at maturity. |
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| Flowers | 5–12 mm diam.; epicalyx bractlets 1–3 mm, 1/2 length of to nearly equal to sepals; hypanthium 1–3 × 2–4 mm, 1/2 to nearly as deep as wide; sepals spreading to ± reflexed, narrowly to broadly lanceolate, (1.7–)2–4(–4.5) mm; petals 2–6(–6.5) mm; filaments 0.2–1.5 × (0.2–)0.4–0.6(–1) mm, anthers 0.4–0.6 mm; styles 0.9–1.5 mm. |
epicalyx bractlets 1.5–2 mm; hypanthium 1.5–2 × 2–3 mm; petals 2–3(–4) mm; filaments 0.2–0.5 mm, wider than long, anthers 0.5 mm; styles 1 mm. |
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| Achenes | brown. |
1.2–1.5 mm. |
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| 2n | = 28. |
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Horkelia fusca |
Horkelia fusca var. tenella |
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| Phenology | Flowering summer. | |||||||||||||||||||||||||
| Habitat | Dry meadow edges, open conifer woodlands, mainly on volcanic soil | |||||||||||||||||||||||||
| Elevation | 1200–2200 m [3900–7200 ft] | |||||||||||||||||||||||||
| Distribution |
CA; ID; NV; OR; WA; WY |
CA |
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| Discussion | Varieties 7 (7 in the flora). Horkelia fusca represents the primary radiation of the genus beyond the California Floristic Province. Within California, H. fusca occurs in the Sierra Nevada and mountains of northern California, and it is the only representative of the genus extending beyond California and Oregon into Washington, Idaho, Nevada [with the possible exception of H. tridentata (10e. sect. Tridentatae) in Washoe County], and, questionably, Wyoming. As here circumscribed, Horkelia fusca is the most diverse, most widely distributed species in the genus, with significant additional work needed to fully elucidate its variation patterns. The treatment presented here differs from that of D. D. Keck (1938) and B. Ertter (1993d) in using the rank variety instead of subspecies, circumscribing var. capitata more narrowly, and transferring the application of var. pseudocapitata from what is here called var. brownii to the bulk of what had been subsp. capitata (Lindley) D. D. Keck (B. Ertter and J. L. Reveal 2007). There are two types of basal leaves in plants of Horkelia fusca. The ephemeral early-season leaves have leaflets that tend to be broadly cuneate-obovate, shallowly toothed, densely glandular but otherwise sparsely hairy, and deeply veined. The leaf features described below are drawn from the more persistent, mid season leaves that predominate at peak flowering and differ more strongly among varieties. Petals of first-formed flowers are often larger than average; end-of-season petals can be smaller than average. Although Montana is sometimes included in the range of Horkelia fusca, such references are based only on potential occurrence (W. E. Booth and J. C. Wright 1959). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Plants of var. tenella have the most deeply and consistently divided leaflets, and the variety is the only one with such leaflets that occurs in California. It is most common in open lodgepole pine forests at the southern end of the Cascade Range in northeastern California. Populations outside this core area tend to intergrade with var. brownii or var. parviflora. A collection from west-central Tehama County (Bracelin 405, UC) matches this variety, but from an atypical habitat well outside the core range. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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| Key |
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| Synonyms | Potentilla douglasii | H. fusca subsp. tenella, Potentilla douglasii var. tenella | ||||||||||||||||||||||||
| Name authority | Lindley: Edwards’s Bot. Reg. 23: plate 1997. (1837) | S. Watson: in W. H. Brewer et al., Bot. California 1: 181. (1876) | ||||||||||||||||||||||||
| Source | FNA vol. 9, p. 259. | FNA vol. 9, p. 261. | ||||||||||||||||||||||||
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