These layers of organic matter are composed almost entirely of carbon, originally drawn from the air by the respiration of plants. Only a meter or so below the surface the soil is perpetually frozen, stunting plant growth and stabilizing the subsurface temperature. Earth scientists and climatologists have long known that the boreal forest plays an important role in global climate, but have been hindered in their studies of the region due to the harsh conditions and remote location. Although much of the boreal forest is composed of conifers like pine and spruce, deciduous birch and aspen add color to some regions. Displays of the northern lights are common during the long winter nights of the high latitude boreal forests.
Gray wolves roam through the wilderness hunting animals such as reindeer, elk, and hares.
Sunlight is one of the most important resources in the boreal forest, where the sun is often low on the horizon.