Geum triflorum |
Geum virginianum |
|||||
---|---|---|---|---|---|---|
old man's beard, old-man's whiskers, prairie smoke, three-flower avens, three-sisters, torchflower |
cream avens, cream or Virginia or pale avens, cream-color avens |
|||||
Habit | Plants subscapose. | Plants leafy-stemmed. | ||||
Stems | 10–45 cm, downy to pilose, hairs 0.1–3 mm, sometimes septate-glandular. |
25–110 cm, puberulent and hirsute to densely hirsute, some hairs 2–2.5 mm. |
||||
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 12–25 cm, blade simple or pinnate, major leaflets 3–5, plus 0–4 minor basal ones, terminal leaflet slightly larger than major laterals; cauline 4–15(–23) cm, stipules ± free, 11–48 × 6–35 mm, blade 3-foliolate or simple and 3-lobed to unlobed. |
||||
Inflorescences | (1–)3–5(–7)-flowered. |
3–14-flowered. |
||||
Pedicels | densely woolly, sometimes glandular. |
puberulent, sometimes with scattered hairs, eglandular. |
||||
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 1–1.5 mm; hypanthium green; sepals spreading but soon reflexed, 3–6 mm; petals spreading, cream, oblong to elliptic, (1.5–)2–3.5 mm, shorter than sepals, apex rounded. |
||||
Fruiting tori | sessile, densely puberulent. |
sessile, densely bristly, hairs 1–2.3 mm. |
||||
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, (3–)4.5–7 mm, apex hooked, glabrate, distal segment deciduous, 1–2 mm, pilose in basal 1/2, hairs much longer than diam. of style. |
||||
Geum triflorum |
Geum virginianum |
|||||
Phenology | Flowering summer. | |||||
Habitat | Mostly forests, river bottoms to dry uplands, rocky slopes, oak-hickory woods | |||||
Elevation | 0–700 m [0–2300 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
|
AL; AR; CT; DC; DE; GA; IL; IN; KY; MA; MD; MI; MO; NC; NJ; NY; OH; OK; PA; RI; SC; TN; VA; VT; WV; ON
|
||||
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.) |
Geum virginianum has been confused nomenclaturally with G. laciniatum. B. L. Robinson and M. L. Fernald (1908) and J. K. Small (1933) misapplied the name G. virginianum to the species correctly named G. laciniatum, and they used the names G. flavum (Robinson and Fernald) and G. hirsutum (Small) for what is correctly named G. virginianum. Much of what is named G. virginianum in older herbarium collections is actually G. laciniatum. In habit and leaf form, Geum virginianum is similar to G. canadense. Geum virginianum differs in having cream petals shorter than the sepals (versus white and usually equal to or longer), the largest stipules of the cauline leaves 20–48 × 10–35 mm (versus smaller), and the stems hirsute to densely hirsute (versus glabrate to downy with only scattered longer hairs). The variability within G. canadense is so great that for some specimens it is difficult to determine whether they belong to G. canadense or G. virginianum. L. A. Raynor (1952) believed Geum virginianum to be an F1 hybrid between G. aleppicum and G. canadense. K. R. Robertson (1974) acknowledged that some herbarium specimens assignable to G. virginianum from the area where G. aleppicum and G. canadense are sympatric have mostly aborted pollen and may represent natural hybrids. He pointed out that farther south, where G. aleppicum is absent, specimens of G. virginianum appear fully fertile and seem to represent a valid species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||
Key |
|
|||||
Source | FNA vol. 9, p. 62. | FNA vol. 9, p. 69. | ||||
Parent taxa | ||||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | Erythrocoma triflora, Sieversia triflora | G. flavum, G. hirsutum | ||||
Name authority | Pursh: Fl. Amer. Sept. 2: 736. (1813) | Linnaeus: Sp. Pl. 1: 500. (1753) | ||||
Web links |
|