Dryas hookeriana

Juzepczuk

Izv. Glavn. Bot. Sada S.S.S.R. 28: 325. 1929.

Common names: Hooker’s mountain-avens
Endemic
Synonyms: Dryas octopetala var. angustifolia C. L. Hitchcock D. octopetala subsp. hookeriana (Juzepczuk) Hultén D. octopetala var. hookeriana (Juzepczuk) Breitung
Treatment appears in FNA Volume 9. Treatment on page 329. Mentioned on page 328.

Plants 1.5–9 cm. Leaf-blades usually oblongelliptic 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. Peduncles 10–30 mm. Flowers 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. Achenes 2.5–3 mm; styles 11–25 mm. 2n = 18.


Phenology: Flowering Jun–Aug.
Habitat: Alpine meadows, dry rocky slopes and ridges, alpine tundra
Elevation: 1500–3900 m

Distribution

V9 538-distribution-map.jpg

Alta., B.C., N.W.T., Alaska, Colo., Idaho, Mont., Oreg., Utah, Wash., Wyo.

Discussion

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.

Selected References

None.

Lower Taxa

None.
... more about "Dryas hookeriana"
woolly +  and tomentose +
2.5mm +  and 3mm +
hairy +, tomentose +  and glabrous +
Joshua C. Springer +  and Bruce D. Parfitt† +
Juzepczuk +
blackish +, reddish +  and brown +
compound +  and simple +
opposite +  and alternate +
cuneate +, cordate +  and truncate +
3.9 cm39 mm <br />0.039 m <br /> (4.6 cm46 mm <br />0.046 m <br />) +
smooth +  and rugose +
ovate +, oval +, obovate +, oblongelliptic +, oblong +, linear +, lanceolate +  and elliptic +
0.2 cm2 mm <br />0.002 m <br /> (3.9 cm39 mm <br />0.039 m <br />) +
stoloniferous +
free +  and distinct +
Hooker’s mountain-avens +
Alta. +, B.C. +, N.W.T. +, Alaska +, Colo. +, Idaho +, Mont. +, Oreg. +, Utah +, Wash. +  and Wyo. +
not +  and aggregated +
1500–3900 m +
stipitate-glandular +  and villous +
1.3 cm13 mm <br />0.013 m <br /> (2.9 cm29 mm <br />0.029 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
linear +  and lanceolate +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Alpine meadows, dry rocky slopes and ridges, alpine tundra +
0.3 cm3 mm <br />0.003 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
crassinucellate +
1.6 cm16 mm <br />0.016 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
persistent +
serrate +  and dentate +
strongly revolute +  and flat +
adaxial +  and abaxial +
stipitate-glandular +, hairy +, glabrous +, tomentose +  and woolly +
inferior +  and superior +
clustered +, biseriate +  and superposed +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Yellow (?) +, Cream (?) +  and White (?) +
persistent +  and deciduous +
free +  and distinct +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
stipitate-glandular +
Flowering Jun–Aug. +
adnate +, free +, connate +  and distinct +
Izv. Glavn. Bot. Sada S.S.S.R. +
not arillate +
persistent +
free +  and distinct +
erect-ascending +, ascending +  and spreading +
lanceolate +  and narrowly elliptic +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
free +  and distinct +
rooting +  and branched +
adnate +  and free +
persistent +
distinct +
basal +, lateral +, subterminal +  and terminal +
elongate +
1.1 cm11 mm <br />0.011 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
smooth +  and slightly plicate +
Dryas octopetala var. angustifolia +, D. octopetala subsp. hookeriana +  and D. octopetala var. hookeriana +
Dryas hookeriana +
species +
inconspicuous +
hemispheric +