Betula nana subsp. nana

Common names: Arctic dwarf birch
Treatment appears in FNA Volume 3.

Shrubs, procumbent, widely spreading, or upright, to 1 m. Bark dark-brown. Twigs sparsely to densely pubescent, dull, without heavy resinous coating, without large, warty, resinous glands. Leaf-blade broadly orbiculate or obovate-orbiculate to reniform, 0.8–1.5 × 0.8–2 cm, base rounded or cuneate to nearly cordate; surfaces abaxially sparsely pubescent to glabrous. Infructescences 0.5–1.5 × 0.4–1 cm; scales glabrous, lobes diverging distal to middle, ascending, about equal in length. 2n = 28.


Phenology: Flowering late spring.
Habitat: Tundra, open rocky barrens, and scrubs, in Europe subalpine mountain moors
Elevation: 0–600 m

Distribution

V3 763-distribution-map.gif

Greenland, N.W.T., n Europe

Discussion

Betula nana subsp. nana occurs in both eastern and western Greenland at latitudes north of 63 degrees. In Europe, the range of this subspecies extends across the subarctic zone and southward in the Alps and other ranges.

Selected References

None.

Lower Taxa

None.

"equal" is not a number."broadest" is not a number. "much narrower" is not a number.

... more about "Betula nana subsp. nana"
John J. Furlow +
Linnaeus +
tanniferous +  and furrowed +
dark-brown +
exfoliating +
cuneate +  and nearly cordate +
2 (?) +  and 3 (?) +
slender +
solitary +  and in small racemose clusters +
ovoid +  and cylindric +
expanding +
Arctic dwarf birch +
multibracteate +
Greenland +, N.W.T. +  and n Europe +
0–600 m +
pistillate +  and staminate +
expanding +
Tundra, open rocky barrens, and scrubs, in Europe subalpine mountain moors +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
1 cm10 mm <br />0.01 m <br /> (4 cm40 mm <br />0.04 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (1 cm10 mm <br />0.01 m <br />) +
membranaceous +
10 cm100 mm <br />0.1 m <br /> (14 cm140 mm <br />0.14 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
inconspicuous +
unexpanded +
distal +  and middle +
not obvious +  and defined +
membranaceous +
Flowering late spring. +
2(-3)-carpellate +
1-seeded +  and 2-winged +
not extended +
crowded +  and imbricate +
deciduous +
(1-)3-lobed +
expanding +
not woody +  and leathery +
thicker +  and thin +
2 (?) +  and 3 (?) +
nearly +  and distinct +
abaxially sparsely pubescent;glabrous +
Betula nana subsp. nana +
Betula nana +
subspecies +
excurrent +  and branching +
differentiated +
shrub +  and procumbent +
upright +  and spreading +
much narrower +
tanniferous +
light +, nearly white +  and reddish-brown +
soft +  and hard +