A montage - overlay of two images where one is the wooden bridge through the woods and the 2nd is a close up of peeling birch bark. The bark is a bit hard to decipher - the lower left is the trunk of the river birch tree and the upper right is the peeling bark (the dark area is the underside of the peeling bark where it's curling off the trunk (more than you ever wanted to know). To me, it gives the effect of peeling something away to more clearly reveal the scene beneath a cover.