peach, fruit tree ( Prunus persica ) of the family Rosaceae (rose family) having decorative pink blossoms and a juicy, sweet drupe fruit. The peach appears to have originated in China, where it was mentioned in literature several centuries before Christ. It was introduced into Persia before Christian times and was spread by the Romans throughout Europe. Several of its horticultural varieties were brought by the Spanish to North America, where it became naturalized as far north as Pennsylvania by the late 17th cent. The numerous varieties of peaches under cultivation are generally distinguished as clingstone or freestone; the latter include the famous Elberta peach. The nectarine is a smooth-skinned peach with both freestone and clingstone varieties. In the United States commercial peach production centers in California and in the S Atlantic states. Elsewhere the peach is cultivated in S Europe, Africa, Japan, and Australia. The tree is prey to frost and is attacked by various fungi, virus diseases, and insect pests, against all of which careful precautions must be taken by growers. Purple-leaved and double-flowering forms are cultivated as ornamentals. In China where the flower is much used in decoration it is considered a symbol of longevity. The peach is closely related to other species of Prunus —e.g., the cherry, plum, and almond—of which Darwin thought the peach was an ancient variety. Peaches are classified in the division Magnoliophyta, class Magnoliopsida, order Rosales, family Rosaceae.