Grove of bent over birches

The magnetic field is so strong up here in the arctic the trees follow the field lines (just like the geology in the film Avatar).

... just kidding. Actually, it is just the weight of the snow that bends the birches over. The spring back up in the thaw, but always have a propensity to bend in the same direction in the following winter. Higher up the snow get so heavy it can break the trees completely.