Due to year round cold temperatures and heavy snowfall plants are stunted or nonexistent at high altitudes. The higher you climb the smaller and more stunted trees become, they are mostly coniferous, the needles get smaller, the limbs get more compact around the trunk. Deciduous plants become extremely limited. Above the tree line, mostly lichens and mosses dominate if the snow recedes. Because of this not very many animals can live at high elevations.