Geum canadense |
Rosaceae subfam. rosoideae |
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benoîte du Canada, white avens |
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Habit | Plants leafy-stemmed. | Herbs, shrubs, or subshrubs. |
Stems | 30–100 cm, glabrate to downy, hairs to 1.5 mm, sometimes glandular. |
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Leaves | basal 10–25 cm, blade simple or pinnate, major leaflets 3–5, plus 0–4 minor basal ones, terminal leaflet larger than major laterals; cauline 3–8 cm, stipules ± free, 4–13 × 1–7 mm, blade 3-foliolate or simple and 3-lobed to unlobed. |
alternate, rarely opposite, pinnately compound, sometimes simple or palmately compound; stipules present, rarely absent. |
Inflorescences | 3–15-flowered. |
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Pedicels | densely hairy, hairs of varying lengths, few long stiff ones, sometimes glandular. |
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Flowers | erect; epicalyx bractlets 0.5–1.5 mm; hypanthium green; sepals spreading but soon reflexed, 3–6 mm; petals spreading, white, obovate to oblong, (3–)4–8 mm, ± equal to or slightly longer than sepals, apex rounded. |
torus usually enlarged, sometimes small or absent; carpels 1–260(–450), distinct, free, styles distinct, rarely connate (Roseae); ovules 1(or 2), collateral (Rubeae) or superposed (Fallugia, Filipendula). |
Fruiting tori | sessile, densely bristly, hairs 1–2.3 mm. |
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Fruiting styles | geniculate-jointed, proximal segment persistent, 2–8 mm, apex hooked, usually glabrous, sometimes sparsely hairy or stipitate-glandular, distal segment deciduous, 1–2 mm, pilose in basal 1/2, hairs much longer than diam. of style. |
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Fruits | achenes or aggregated achenes sometimes with fleshy, urn-shaped hypanthium or enlarged torus, sometimes aggregated drupelets; styles persistent or deciduous, not elongate (elongate but not plumose in Geum). |
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x | = 7(8). |
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2n | = 42. |
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Geum canadense |
Rosaceae subfam. rosoideae |
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Phenology | Flowering spring–summer. | |
Habitat | Lowlands and upland forests, meadows, along streams, thickets, bottomland hardwoods, swamps | |
Elevation | 0–600 m (0–2000 ft) | |
Distribution |
AL; AR; CT; DC; DE; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; WY; MB; NB; NS; ON; PE; QC; Mexico (Chiapas)
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North America; Mexico; Central America; South America; West Indies; Bermuda; Eurasia; Africa; Atlantic Islands; Indian Ocean Islands; Pacific Islands; Australia |
Discussion | Varieties and forms have been described in an effort to classify the variation encompassed in Geum canadense. In the eastern half of the United States, it is by far the most common, widespread, and variable of the Geum species. Nearly all writers of recent floras have not found it worthwhile to apply names to the variants. Perhaps the most distinctive and worthy of further consideration are plants from the southwestern corner of the range in Arkansas, Oklahoma, and Texas. These plants, some of which fit Fernald and Weatherby’s description of var. texanum, bloom from late March through May, significantly earlier than the rest of the species, which typically flowers after June first, even in the other southern states. Geum canadense hybridizes with G. urbanum (= G. ×catlingii J.-P. Bernard & R. Gauthier); see discussion under 15. G. urbanum. Geum album J. F. Gmelin is a superfluous name that pertains here. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Variation in the number of genera in subfam. Rosoideae is due to differences in generic delimitation between D. Potter et al. (2007) and the authors of some Potentilleae genera. Cyanogenic glycosides and sorbitol are absent in the subfamily. Tribes 6, genera 28–35, species ca. 1600 (6 tribes, 26 genera, 302 species, including 1 hybrid, in the flora) (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 68. | FNA vol. 9, p. 23. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Colurieae > Geum | Rosaceae |
Sibling taxa | ||
Subordinate taxa | ||
Synonyms | G. camporum, G. canadense var. brevipes, G. canadense var. camporum, G. canadense var. grimesii, G. canadense var. texanum | |
Name authority | Jacquin: Hort. Bot. Vindob. 2: 82, plate 175. 1772–1773 | Arnott: Botany, 107. (1832) |
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