Rowan Several of the Asian species are widely cultivated as ornamental trees. North American native species in the subgenus "Sorbus (Sorbus)" include the American mountain-ash "Sorbus americana" and Showy mountain-ash "Sorbus decora" in the east and Sitka mountain-ash "Sorbus sitchensis" in the west. Numerous hybrids, mostly behaving as true species reproducing by apomixis, occur between rowans and whitebeams; these are variably intermediate between their parents but generally more resemble whitebeams and are usually grouped with them (q.v.). Rowans are excellent small ornamental trees for parks, gardens and wildlife areas. Several of the Chinese species, such as White-fruited rowan ("Sorbus glabrescens") are
Sorbus aucuparia tart, and aromatic, and candied or used in compote. The two cultivars are self-pollinating, yield fruit early, and the sugar content increases while the acid content decreases as the fruit ripen. 'Beissneri' is a cultivar with reddish foliage and bark and serrated leaves. Other edible varieties originate in and are named after Klosterneuburg, Lower Austria. Russian botanist Ivan Vladimirovich Michurin began in 1905 to crossbreed common "S. aucuparia" with other species to create fruit trees. His experiments resulted in the cultivars 'Burka', 'Likjornaja', 'Dessertnaja', 'Granatnaja', 'Rubinovaja', and 'Titan'. Other "S. aucuparia" hybrids planted in Western Europe beginning in the 1980s