Geum triflorum |
Geum radiatum |
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old man's beard, old-man's whiskers, prairie smoke, three-flower avens, three-sisters, torchflower |
Appalachian avens, spreading avens |
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Habit | Plants subscapose. | Plants subscapose. | ||||
Stems | 10–45 cm, downy to pilose, hairs 0.1–3 mm, sometimes septate-glandular. |
10–45(–60) cm, densely hirsute proximally to puberulent distally. |
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Leaves | basal 4–30 cm, blade interruptedly pinnate, major leaflets 10–18, alternating with 6–16 minor ones gradually increasing in size distally, terminal leaflet slightly larger than major laterals; cauline 1–5 cm, stipules adnate to leaf, indistinguishable from leaflets/lobes, blade bractlike, not resembling basal, opposite, pinnate-pinnatifid. |
basal 10–30 cm, blade strongly lyrate-pinnate, sometimes simple, major leaflet 1, minor leaflets 1–6, terminal leaflet much larger than minor laterals; cauline 1.2–4 cm, stipules not evident, blade bractlike, not resembling basal, simple. |
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Inflorescences | (1–)3–5(–7)-flowered. |
3–10-flowered. |
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Pedicels | densely woolly, sometimes glandular. |
glandular-hairy. |
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Flowers | nodding, erect in fruit; epicalyx bractlets 6–15 mm; hypanthium maroon, purple, or greenish mottled with purple, may turn pale brown in fruit; sepals erect, 7–14 mm; petals erect, cream to yellowish suffused with pink or purple, or purple-veined, elliptic, 7–13 mm, shorter to longer than sepals, apex rounded to obtuse. |
erect; epicalyx bractlets 2–5 mm; hypanthium green; sepals spreading in flower, erect in fruit, 6–10 mm; petals spreading, yellow, orbiculate to obcordate, 9–16 mm, longer than sepals, apex emarginate. |
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Fruiting tori | sessile, densely puberulent. |
sessile, glabrous. |
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Fruiting styles | wholly persistent or distal 3–7 mm tardily deciduous, not or inconspicuously geniculate-jointed, 15–70 mm, apex not or occasionally ± hooked, pilose to apex or nearly so. |
wholly persistent, not geniculate-jointed, 8–12 mm, apex not hooked, pilose and stipitate-glandular in basal 1/3. |
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2n | = 42. |
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Geum triflorum |
Geum radiatum |
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Phenology | Flowering summer. | |||||
Habitat | Rocky cliffs and ledges, montane balds | |||||
Elevation | 1500–1900 m [4900–6200 ft] | |||||
Distribution |
AZ; CA; CO; IA; ID; IL; MI; MN; MT; ND; NM; NV; NY; OR; SD; UT; WA; WI; WY; AB; BC; MB; NT; ON; SK; YT; Mexico
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NC; TN |
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Discussion | Varieties 2 (2 in the flora). At the beginning of the twentieth century, E. L. Greene described over a dozen species belonging to the Geum triflorum complex based on differences in leaf form and indument, the relative length and shape of the epicalyx bractlets and sepals, and petal length and shape. Most of these species were quickly reduced to synonymy by other botanists. When specimens are examined from across the continent, most of the characters used to separate species in the G. triflorum complex show nearly continuous variation. It seems best to treat these variants as belonging to one species. Whether and how to classify the variation within the species will remain controversial. Some character expressions correlate reasonably well with dividing the species into two varieties, as was first proposed by N. C. Fassett (1928). Variety triflorum occurs east of the Rocky Mountains and is typical of the grasslands covering the northern Great Plains; it also is the variety found in the mountains of Arizona and New Mexico. Variety ciliatum is common throughout the rest of the Rocky Mountains, the Sierra Nevada, and Cascade Range. Intermediate specimens occur here and there, particularly in Alberta and British Columbia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Geum radiatum is closely related to G. calthifolium and G. peckii. The morphologic differences among them are slight compared to the discontinuities separating other Geum species. On the basis of morphology it would be possible to combine all three in a single species. Yet they occupy distinct ranges separated by a minimum of 1200 km. Traditionally, they have been treated as separate species, and recently I. G. Paterson and M. Snyder (1999) reported molecular genetic evidence for continuing to recognize G. peckii and G. radiatum as separate species. Geum radiatum is listed as an endangered species by the U.S. Fish and Wildlife Service. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 9, p. 62. | FNA vol. 9, p. 64. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Erythrocoma triflora, Sieversia triflora | Sieversia radiata | ||||
Name authority | Pursh: Fl. Amer. Sept. 2: 736. (1813) | Michaux: Fl. Bor.-Amer. 1: 300. (1803) | ||||
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