Western Sandbar Willow - Salix exigua
This small tree (20 feet) or shrub can form large clonal thickets alongside streams and on open sandbars. It grows to elevations of 5,800 feet and is one of those unusual species that is found both east and west of the Rocky Mountains. It is absent from the East and from the coastline. The leaves are narrow and up to 6 inches long, hairy beneath, with a pointed tip and base, and typically untoothed. The catkins open after the leaves and are sometimes more than 3 inches in length; the male flowers have 2 stamens. The seeds are tiny.