Plum (Prunus spp.)
Plums closely resemble small nectarines in shape, although some may be oval instead of round. Like nectarines, they have a crease on one side. The flesh and skin color vary greatly with cultivar (yellow, green, red, blue or purple) and unlike nectarines, the color is not mottled. The skin is smooth and thin; the stone is usually oval, pointed at one end, and slightly rough. Leaves are alternate, shape also varies with cultivar but is usually wider and shorter than peach, being more or less ovate (egg-shaped), with finely serrate margins. Showy white flowers have 5 petals and prominent stamens. Tree shape varies from spreading to upright, depending on cultivar.