Birch or Alder are both types of trees. They are both deciduous trees, meaning they lose their leaves in the fall and grow new ones in the spring. Birch trees are usually found in cooler climates, while Alder trees are more common in warmer climates. Both trees have a light colored bark and can reach heights of up to 30 meters. Birch trees are often used for making furniture, while Alder trees are used for making musical instruments.