The Genus Sorbus

1. Cascade Mountain Ash: Sorbus scopulina - Small tree to 12 feet. Flowers small, white, in round clusters like an overturned plate (cyme). Leaves compound pinnate, very shiny, with small serrations along the full length of the leaflet margins. Leaflets number 9-13 with acute to acuminate tips.

2. Sitka Mountain Ash: Sorbus sitchensis - Small tree to 12 feet. Flowers small, white, in round clusters like an overturned plate (cyme). Leaves compound pinnate, a dull blue-green, with small serrations along the distal 1/2-2/3 of the margins of the leaflets. Leaflets number 7-11 with blunt to rounded tips.