Geum rossii

(R. Brown) Seringe in A. P. de Candolle and A. L. P. P. de Candolle

in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 2: 553. 1825.

Common names: Ross’s avens
Basionym: Sieversia rossii R. Brown Chlor. Melvill., 18, plate C. 1823
Synonyms: Acomastylis rossii (R. Brown) Greene Geum rossii var. depressum (Greene) C. L. Hitchcock G. rossii var. turbinatum (Rydberg) C. L. Hitchcock G. turbinatum S. gracilipes
Treatment appears in FNA Volume 9. Treatment on page 63. Mentioned on page 60, 64.

Plants subscapose. Stems 4–28 cm, glabrous or downy, hairs to 1 mm, sometimes septate-glandular. Leaves: basal 3–13 cm, blade pinnate to interruptedly pinnate, major leaflets 13–26, alternating with 0–14 minor ones, terminal leaflet slightly larger than major laterals; cauline 0.7–2 cm, stipules adnate to leaf, indistinguishable from pair of lobes, blade bractlike, not resembling basal, alternate, simple, pinnatifid to 3-fid. Inflorescences 1–3 (–4) -flowered. Pedicels woolly, sometimes glandular. Flowers erect; epicalyx bractlets 1.5–7 mm; hypanthium green, slightly purple-tinged to strongly purple; sepals erect to erect-spreading, 3–10 mm; petals spreading, yellow, obovate to nearly orbiculate, 5–12 (–17) mm, longer than sepals, apex broadly rounded to irregularly emarginate. Fruiting tori sessile, glabrous. Fruiting styles wholly persistent, not geniculate-jointed, 2–5 (–10) mm, apex not hooked, glabrous throughout or pilose only at base. 2n = 56.


Phenology: Flowering summer.
Habitat: Alpine and arctic tundra, rocky slopes, often in gravelly or peaty soil
Elevation: 0–4000 m

Distribution

V9 88-distribution-map.jpg

Greenland, B.C., N.W.T., Nunavut, Yukon, Alaska, Ariz., Colo., Idaho, Mont., Nev., N.Mex., Oreg., Utah, Wash., Wyo., e Asia (Russian Far East)

Discussion

The variability accommodated here in Geum rossii was distributed by earlier monographers such as P. A. Rydberg (1913b) and F. Bolle (1933) among a half dozen species. W. Gajewski (1957) reduced them to two species, G. rossii and G. turbinatum; most recent taxonomists have recognized the two taxa as subspecies or varieties of a single species. The large geographic discontinuity between the Rocky Mountain and arctic ranges makes it easy for those wishing to follow this tradition. No one morphologic character or combination of characters neatly separates the arctic plants from those of the Rockies.

Where their ranges overlap in Alaska, Geum rossii hybridizes with G. calthifolium to form sterile plants known as G. ×macranthum (Kearney ex Rydberg) B. Boivin; see discussion under 4. G. schofieldii.

Selected References

None.

Lower Taxa

None.
... more about "Geum rossii"
pilose +  and glabrous +
Joseph R. Rohrer +
(R. Brown) Seringe in A. P. de Candolle and A. L. P. P. de Candolle +
compound +  and simple +
opposite +  and alternate +
3 cm30 mm <br />0.03 m <br /> (13 cm130 mm <br />0.13 m <br />) +
Sieversia rossii +
not alternate +
pinnatifid +  and 3-fid +
free +  and distinct +
0.7 cm7 mm <br />0.007 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Ross’s avens +
Greenland +, B.C. +, N.W.T. +, Nunavut +, Yukon +, Alaska +, Ariz. +, Colo. +, Idaho +, Mont. +, Nev. +, N.Mex. +, Oreg. +, Utah +, Wash. +, Wyo. +  and e Asia (Russian Far East) +
not +  and aggregated +
0–4000 m +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (4.6 cm46 mm <br />0.046 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
tapered +, ovoid +  and fusiform +
0.2 cm2 mm <br />0.002 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Alpine and arctic tundra, rocky slopes, often in gravelly or peaty soil +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
slightly purple-tinged +  and strongly purple +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crassinucellate +
odd-pinnate +, lyrate-pinnate +, 3-foliolate +  and simple +
opposite +  and alternate +
winter-persistent +
cauline +  and basal +
cordate +, reniform +, orbiculate +, oblanceolate +, obovate +, oblong +, elliptic +  and rhombic +
palmate +  and pinnate +
crenate +, dentate +, laciniate +, 2-7-lobed +, flat +, lobed +, toothed +  and entire +
inferior +  and superior +
clustered +, biseriate +  and superposed +
purple-veined +
0 (?) +  and 4 (?) +
1.2 cm12 mm <br />0.012 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
free +  and distinct +
0.5 cm5 mm <br />0.005 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Flowering summer. +
adnate +, free +, connate +  and distinct +
in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. +
not arillate +
persistent +
free +  and distinct +
erect +  and erect-spreading +
deltate-lanceolate +, deltate-ovate +  and deltate +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
free +  and distinct +
1 +  and 5 +
4 cm40 mm <br />0.04 m <br /> (28 cm280 mm <br />0.28 m <br />) +
palmate +  and pinnate +
indistinguishable +
geniculate-jointed +  and entire +
persistent +
distinct +
elongating +
basal +, lateral +, subterminal +  and terminal +
hairy +  and glabrous +
not hooked +  and hooked +
accrescent +
10 cm100 mm <br />0.1 m <br /> (?) +
Acomastylis rossii +, Geum rossii var. depressum +, G. rossii var. turbinatum +, G. turbinatum +  and S. gracilipes +
Geum rossii +
species +
slightly larger +
inconspicuous +
hemispheric +  and cylindric +
enlarged +
not geniculate-jointed +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
hairy +  and glabrous +