Showy mountain-ash is very similar to the closely related American mountain-ash ("Sorbus americana"). The tree species Sorbus americana is commonly known as the American mountain-ash. "Sorbus americana" is a relatively small tree, reaching in height. "Sorbus americana" is cultivated as an ornamental tree, for use in gardens and parks. A cultivar is the red cascade mountain-ash, or "Sorbus americana" 'Dwarfcrown'.