Prunus apricots, of cherries, and of plums, all of which have cultivars developed for commercial fruit and nut production. The almond is not a true nut, the edible part is the seed. Other species are occasionally cultivated or used for their seed and fruit. A number of species, hybrids, and cultivars are grown as ornamental plants, usually for their profusion of flowers, sometimes for ornamental foliage and shape, and occasionally for their bark. The Tree of 40 Fruit has forty varieties grafted on to one rootstock. Species such as blackthorn ("Prunus spinosa"), are grown for hedging, game cover, and other utilitarian
Prunus cerasus Montmorency cherry is the most popular type of sour cherry in America. The reason for its popularity is its use in baking and recipe creation. including cherry pies, cherry desserts and other cherry-based recipes. "Prunus cerasus", a tetraploid with 2n=32 chromosomes, is thought to have originated as a natural hybrid between "Prunus avium" and "Prunus fruticosa" in the Iranian Plateau or Eastern Europe where the two species come into contact. "Prunus fruticosa" is believed to have provided its smaller size and sour tasting fruit. The hybrids then stabilised and interbred to form a new, distinct species. Cultivated sour cherries were