Geum calthifolium
Geum canadense
caltha-leaf avens
benoîte du Canada, white avens
8–40 cm, sparsely hirsute proximally, puberulent throughout.
30–100 cm, glabrate to downy, hairs to 1.5 mm, sometimes glandular.
basal 5–25 cm, blade strongly lyrate-pinnate, sometimes simple, major leaflet 1, minor leaflets 1–7, terminal leaflet much larger than minor laterals;
cauline 1.5–4.5 cm, stipules not evident, blade bractlike, not resembling basal, simple.
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.
1–2(–4)-flowered.
3–15-flowered.
downy, hirsute, eglandular.
densely hairy, hairs of varying lengths, few long stiff ones, sometimes glandular.
erect;
epicalyx bractlets 2–6 mm;
hypanthium green or green with slight maroon tinge;
sepals erect-spreading, 6–11 mm;
petals spreading, yellow, obcordate-obdeltate to nearly orbiculate, 9–13 mm, longer than sepals, apex broadly and shallowly emarginate.
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.
sessile, glabrous.
sessile, densely bristly, hairs 1–2.3 mm.
wholly persistent, not geniculate-jointed, 9–14 mm, apex not hooked, pilose in basal 3/4, eglandular.
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.
= 42.
= 42.
Geum calthifolium
Geum canadense
Geum calthifolium hybridizes with G. rossii [= G. ×macranthum (Kearney ex Rydberg) B. Boivin]; see discussion under 4. G. schofieldii.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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.)
BC- Local Web sites:
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
LA Plants, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria 
WildflowerSearch
iNaturalist (observations)
USDA Plants Database- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
