Mountain ash is a small, shrubby tree that grows 10-40 ft in height. The white flowers are found in clusters called 'cymes' and often bloom in the spring or very early summer.The fruits are also in clusters and are bright orange to red. They generally ripen in the fall. Leaves of this tree resemble a sumac with 11-17 narrow, pointy leaflets in each compound leaf. Each leaflet is 4-8 times longer than it is wide and has sharply toothed edges. The bark of Mountain ash is gray and smooth to scaly. Fall color is salmon red or yellow.

Bears are often found in Mountain ash trees when the berries are ripe. Many other animals also enjoy the berries including moose, white-tailed deer and several species of grouse. Birds that eat the berries are said to become mildly drunk. When the fruits appear in September, fall colors are soon to follow.