Betulaceae birch family

The birch or Betulaceae family includes 6 genera of deciduous trees and shrubs, the birches, alders, hazels, hornbeams, hazel-hornbeams, and hop-hornbeams, with about 167 species in all. They are mostly native to the temperate Northern Hemisphere.

• Leaves are simple, alternate, typically single or double-toothed, with a central vein and straight or near-straight lateral veins.
• Trees are monoecious (both males and females on the same tree).
• Male inflorescences are typically pendant catkins, often appearing before leaves in spring.
• Female inflorescences take a variety of forms, from single flowers to erect or pendulous aggregations of flowers.
• Fruit varies from a single-seeded nut to a samara.