Seek out these specific trees:

Cottonwoods have triangular leaves grow on flattened leaf stalks in an alternating pattern. 

Beech has oval-shaped leaves with wavy edges, very smooth light grey bark.  Beech nuts grow in bristly triangular-shaped husks 

Alders have oval leaves with rounded or indented tips, and deeply serrated edges, arranged in an alternating pattern

Maples have hand-shaped leaves with 3-5 lobes that grow in pairs opposite from each other.  Maples have winged helicopter seeds​

Birch has oval or elliptical leaves with a pointed tips and finely serrated edge, the bark of Paper Birch can peal off into curls

Oak leaves are long and irregularly lobbed, Oaks make acorns