Betula nana – Arctic Birch (Alps, north-German flatlands, northern Europe)
Habit: Small shrub, 0.2-0.6 m, rarely up to 1.2 m tall and wide; prostrate to arching upright; slow-growing.
Flowers: Inconspicuous catkins, green, April.
Leaves: Small, circular, dark green, orange-yellow to flaming red in autumn, October.
Roots: Shallow roots.
Demands: Sunny, not tolerating shade, sensitive to heat and drought, likes cool areas with high humidity, extremely frost hardy; moist to damp; very acidic to neutral, very intolerant of chalk; prefers bog soil or peat, also sandy-loamy substrates, wind resistant.
Hardiness: Zone 1