The genus Sorbus (rowan) presents something of a conundrum for taxonomists, with much debate about which species to include within the genus. It is currently generally accepted that the genus comprises approximately 100 species of trees and shrubs from the temperate northern hemisphere. S. torminalis (syn. Torminalis glaberrima), or the wild service tree, is a native of north Africa, south west Asia and Europe, where its range extends to England. It is seldom seen in gardens, though thrives in clay and chalky soils. Reaching over 25m in height it bears lobed, glabrous foliage. In June it produces open corymbs of white flowers, and bears oval-round, brown fruits in autumn, which are referred to as chequers in southern England.