Water Birch - Betula occidentalis

 This tree that likes to grow right next to streams is water birch (Betula occidentalis), which is in the Birch Family (Betulaceae), the only member of that family in this area. It grows in western North America.

 Leaves are bright green and heart-shaped, with a dentate margin. Catkins grow along the twigs.

The bark for water birch is red with white spots. Older bark gets shaggy and starts peeling off.

For more info about water birch, see this USU webpage.