European Mountain-ash, European Mountain Ash, Rowan: Sorbus aucuparia (Synonym: Pyrus aucuparia) -
California Mountain Ash: Sorbus californica (Synonym: Sorbus sitchensis ssp. californica) -
Oakleaf Mountain Ash, Swedish Mountain-ash, Swedish Service-tree: Sorbus hybrida -
Cascade Mountain Ash, Greene's Mountain Ash, Rocky Mountain Mountain Ash: Sorbus scopulina (Synonyms: Pyrus scopulina, Sorbus cascadensis, Sorbus scopulina var. cascadensis, Sorbus scopulina var. 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.
Dwarf Mountain Ash, Gray's Mountain Ash, Sitka Mountain Ash, Western Mountain Ash: Sorbus sitchensis var. grayi (Synonyms: Pyrus sambucifolia var. pumila, Pyrus occidentalis, Sorbus occidentalis, Sorbus pumilus, Sorbus sambucifolia var. pumila, Sorbus sitchensis ssp. grayi) - 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.
Sitka Mountain Ash, Sitka Mountain-ash: Sorbus sitchensis var. sitchensis (Synonyms: Sorbus americana, Sorbus americana var. sitchensis) -