Betula nana Betula nana Betula nana, the dwarf birch, is a species of birch in the family Betulaceae, found mainly in the tundra of the Arctic region. It is a monoecious shrub growing up to 1–1.2 m high. The bark is non-peeling and shiny red-copper colored. The leaves are rounded, 6–20 mm diameter, with a bluntly toothed margin. The leaves are a darker green on their upper surface. Leaf growth occurs after snow melt and become red in autumn. The wind-pollinated fruiting catkins are erect, 5–15 mm long and 4–10 mm broad. "Betula nana" is native to arctic and cool temperate regions
Thuja occidentalis its common names, it is not a true cedar in the genus "Cedrus", nor is it related to the Australian white cedar, "Melia azedarach". Unlike the closely related western red-cedar ("Thuja plicata"), northern white-cedar is only a small or medium-sized tree, growing to a height of tall with a trunk diameter, exceptionally to tall and diameter. The tree is often stunted or prostrate in less favorable locations. The bark is red-brown, furrowed and peels in narrow, longitudinal strips. Northern white-cedar has fan-like branches and scaly leaves. The foliage forms in flat sprays with scale-like leaves long. The seed cones are