The birches form a family with 6 genera and about 100 species that occur mostly throughout the cooler northern climates. Most are shrubs. In the U.P. there are four tree-sized species. They all have simple leaves with saw-toothed margins . Family members frequently bear male catkins which form in the fall and flower in the spring.
Female catkins form in the spring.
The two birches have small samaras shaped like turkey feet that fall from papery cones. Ironwood and musclewood have unique fruits. The bright white, peeling BARK of paper birch make this tree one of the easiest in the northwoods to identify. Leaf margins are serrated or double-serrated . They look like tiny turkey feet and can often be found atop the snow throughout the winter.