Prunus spinosa insect-pollinated. The fruit, called a "sloe", is a drupe in diameter, black with a purple-blue waxy bloom, ripening in autumn and harvested – traditionally, at least in the UK – in October or November after the first frosts. Sloes are thin-fleshed, with a very strongly astringent flavour when fresh. "Prunus spinosa" is frequently confused with the related "P. cerasifera" (cherry plum), particularly in early spring when the latter starts flowering somewhat earlier than "P. spinosa". They can be distinguished by flower colour, creamy white in "P. spinosa", pure white in "P. cerasifera". They can also be distinguished in winter by
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