Scientific Noun:"Prunus avium L". Most cherry species are native to the Northern Hemisphere, where they are widely grown. Some 10 to 12 species are recognized in North America and a similar number in Europe. The greatest concentration of species, however, appears to be in eastern Asia.Three types of cherry are mainly grown for their fruit. These are the sweet cherries, P. avium, the sour, or tart, cherries, P. cerasus, and, grown to a much smaller extent, the dukes, which are crosses of sweet and sour cherries. Sweet-cherry trees are large and rather upright, attaining heights up to 11 metres (36 feet). The fruit is generally heart-shaped to nearly globular, about 2 centimetres (1 inch) in diameter, and varies in colour from yellow through red to nearly black. The acid content of the sweet cherry is low; the higher acid content of the sour cherry produces its characteristic tart flavour. Sour-cherry trees are smaller, rarely over 5 metres (16 feet) in height.