The term 'Trees in the Birch Family' refers to a group of trees that belong to the Betulaceae family, which includes alders (6 letters). Alders are deciduous trees that are native to temperate and subtropical regions of the Northern Hemisphere. They are characterized by their smooth, gray bark and small, round leaves. Alders are often found near water sources, such as streams and rivers, and they are known for their fast growth rate.