An early sign of Spring to look for in our forests are tree circles. At this time of year, trees absorb sunlight (which excites electrons, creating heat) which is then radiated outward, melting snow. The darker the bark, the more radiant heat is created and the wider the circle becomes. Snow, being white, does just the opposite, it reflects sunlight. These melting circles are not just limited to trees, however. Inanimate objects, such as rocks, etc. also exhibit this phenomenon.