Geum triflorum |
Geum laciniatum |
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old man's beard, old-man's whiskers, prairie smoke, three-flower avens, three-sisters, torchflower |
benoîte lacinicée, floodplain avens, hairy herb-bennet, rough avens |
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Habit | Plants subscapose. | Plants leafy-stemmed. | ||||
Stems | 10–45 cm, downy to pilose, hairs 0.1–3 mm, sometimes septate-glandular. |
30–100 cm, hirsute, some hairs 2–2.5 mm. |
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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 15–32 cm, blade simple, lyrate-pinnate, or pinnate, major leaflets 1–7, alternating with 0–10 minor leaflets, terminal leaflet slightly to much larger than major laterals; cauline 3.5–18 cm, stipules ± free, 4–14 × 7–17 mm, blade pinnate, 3-foliolate, or simple and unlobed. |
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Inflorescences | (1–)3–5(–7)-flowered. |
2–9-flowered. |
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Pedicels | densely woolly, sometimes glandular. |
densely puberulent, hirsute, eglandular. |
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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 1–2 mm; hypanthium green; sepals spreading but soon reflexed, 3–10 mm; petals spreading, white, oblong to elliptic, 2–5 mm, shorter than sepals, apex obtuse to rounded. |
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Fruiting tori | sessile, densely puberulent. |
sessile, glabrous except for ring of bristles at base and tuft at apex. |
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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. |
geniculate-jointed, proximal segment persistent, 2.5–5 mm, apex hooked, glabrous, sometimes 1–2 eglandular bristles at base, distal segment deciduous, 1–2 mm, short hairs on basal 1/2. |
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2n | = 42. |
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Geum triflorum |
Geum laciniatum |
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Phenology | Flowering early summer. | |||||
Habitat | Wet woods and thickets, flood plains, wet woods around lakes, stream banks, boggy meadows | |||||
Elevation | 0–1000 m [0–3300 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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CT; DC; DE; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; NC; NE; NH; NJ; NY; OH; PA; RI; SD; TN; VA; VT; WI; WV; NB; NS; ON; PE; QC
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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.) |
B. L. Robinson and M. L. Fernald (1908) and J. K. Small (1933) misapplied the name Geum virginianum to this species. As a consequence, older specimens of G. laciniatum are often labeled (and filed in herbaria) as G. virginianum. Geum laciniatum is unique among members of the genus in having some of the heads of achenes pop off the stem and disperse as a unit. The heads disarticulate where the torus joins the hypanthium, leaving the hypanthium inverted at the tip of the stem. Fernald described var. trichocarpum based on the presence of bristles on the summits of the achenes. Although this morphology occurs to the near exclusion of the glabrous one in the western part of the species range, it also occurs as far east as the Carolinas, Maine, New Jersey, and Virginia. The glabrous condition has a smaller range, and it is the prominent one in Nova Scotia, Kentucky, Maine, and Ohio. The two are well mixed in Quebec, New York, and Pennsylvania. Although they are easily distinguished (hairs absent versus present), they seem to have little phytogeographic significance, and presence of achene hairs is not correlated with any other characteristics. It appears to be a trivial variation. Geum laciniatum hybridizes with G. urbanum (= G. ×macneillii J.-P. Bernard & R. Gauthier); see discussion under 15. G. urbanum. (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. 68. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Erythrocoma triflora, Sieversia triflora | G. laciniatum var. trichocarpum | ||||
Name authority | Pursh: Fl. Amer. Sept. 2: 736. (1813) | Murray: Novi Comment. Soc. Regiae Sci. Gott. 5: 30, plate 2. (1775) | ||||
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