How do trees know it's spring? What happens if leaves come out too early? How do my leaves fit into the food chain? Is it true that some songbirds arrive from the Tropics just as the leaves emerge on my trees? Explore these and other questions by reporting when leaves emerge on your trees.

Sugar Maple

Leaf-out map

Report when leaves are the size of a U.S. quarter.

Flowering Dogwood


Quaking Aspen


  • Adopt a local tree of one of the species above.
  • Visit your adopted tree on a regular basis. Sketch the buds on the same small branch each time you visit.
  • Watch the bud open, the tree bloom, and the leaves emerge.
  • Report to Journey North when your tree's leaves are the size of a U.S. (or Canadian) quarter—our definition of "leaf-out."
  • Using Leaf-out data reported by others, map spring's progress across the hemisphere: