Invisible forces in mountain forests

On a slope, the blanket of snow gradually slides downhill, advancing by a few millimetres to a few centimetres a day. This force, known as snowpack creep, causes some softwood trees to bend. One cubic metre of wet snow weighs around 400 kg. This causes the tree to deform into a crooked shape, typical of the Alpine landscape, or to bend or break. This phenomenon is sometimes crucial to a tree's lifespan and stability. Snow often causes longitudinal tears in the trunk, leaving the tree vulnerable to parasites and disease.