The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links
Dryas hookeriana

Hooker's mountain-avens, mountain avens, white dryas, White Mountain-avens

Drummond's mountain-avens, dryade de Drummond, mountain avens, yellow mountain dryas, yellow mountain-avens

Habit Plants 1.5–9 cm. Plants 2–23 cm.

blades usually oblong-elliptic to lanceolate, sometimes ovate, 4–16(–25) × 1–6(–10) mm, base usually truncate or cordate, sometimes cuneate, margins strongly revolute to flat, coarsely dentate or serrate, sinuses 5–25(–30)% to midvein, apex acute to obtuse, surfaces smooth to slightly plicate, only midvein ± obscured adaxially within medial fold, abaxial tomentose to woolly (obscuring lateral veins), adaxial usually glabrous, sometimes sparsely hairy proximally on midvein, feathery hairs usually absent, rarely 1+ on midveins abaxially, midveins and petioles abaxially stipitate-glandular.

blades oblong-elliptic to obovate, 4–38(–46) × 2–24 mm, base usually cuneate, sometimes truncate or cordate, margins flat, crenate, dentate, or ± serrate, sinuses 10–25% to midvein, apex rounded to obtuse, surfaces smooth, tomentose, feathery hairs and stipitate glands absent or on midveins and petioles;

basal leaflets 1(–2), 0.5–3 × 0.5–2 mm.


10–30 mm.

40–263 mm.


erect at flowering;

sepals lanceolate to narrowly elliptic, 4–10 × 0.6–1.5 mm;

petals 8, spreading, usually white or cream, sometimes yellow, 9–14 × 5–11 mm;

filaments glabrous.

nodding at flowering;

sepals ovate, 4–6 × 3–4 mm;

petals 8–10(–12), erect, yellow, 8–12 × 4–7 mm;

filaments hairy.


2.5–3 mm;

styles 11–25 mm.

2.5–3 mm;

styles 15–39 mm.


= 18.

= 18.

Dryas hookeriana

Dryas drummondii

Phenology Flowering Jun–Aug. Flowering Jun–Aug(–Sep).
Habitat Alpine meadows, dry rocky slopes and ridges, alpine tundra Sandy and gravelly beaches, flood plains, stream bars, rocky streams, grassy areas, alpine, calcicolous
Elevation 1500–3900 m (4900–12800 ft) 0–3000 m (0–9800 ft)
from FNA
[WildflowerSearch map]
from FNA
[WildflowerSearch map]
[BONAP county map]

In some states and provinces, the distribution of Dryas hookeriana is restricted to northwestern and central Colorado, southeastern and northernmost Idaho, western and central Montana, northeastern Utah (Uinta and Wasatch mountains), eastern Oregon and Washington, southwestern and central Wyoming, and western Northwest Territories.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

In some states and provinces, Dryas drummondii has a limited distribution: northwestern Saskatchewan, Lake Superior islands of Ontario (relatively rare elsewhere in Ontario), Gaspé Peninsula, Quebec, northern Montana (Glacier National Park and surrounding area), and northeastern Oregon.

Dryas ×suendermannii Kellerer ex Sündermann, a hybrid between D. drummondii and D. hookeriana, has been reported from Alberta (J. G. Packer 1994). The hybrid shares with D. drummondii abaxial median and lateral leaf veins covered by tomentum, not viscid, stipitate glands absent; adaxial surface not viscid, and punctate glands absent. The hybrid shares with D. hookeriana an adaxially shiny leaf surface. It is intermediate in feathery hairs occasionally present (absent in D. hookeriana).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 9, p. 329. FNA vol. 9, p. 328.
Parent taxa Rosaceae > subfam. Dryadoideae > tribe Dryadeae > Dryas Rosaceae > subfam. Dryadoideae > tribe Dryadeae > Dryas
Sibling taxa
D. ajanensis, D. alaskensis, D. drummondii, D. incisa, D. integrifolia, D. octopetala
D. ajanensis, D. alaskensis, D. hookeriana, D. incisa, D. integrifolia, D. octopetala
Synonyms D. octopetala var. angustifolia, D. octopetala subsp. hookeriana, D. octopetala var. hookeriana D. drummondii var. eglandulosa, D. drummondii var. tomentosa, D. octopetala var. drummondii, D. tomentosa
Name authority Juzepczuk: Izv. Glavn. Bot. Sada S.S.S.R. 28: 325. (1929) Richardson ex Hooker: Bot. Mag. 57: plate 2972. (1830)
Web links