Wild plums generally refer to several native North American species, most commonly the American plum (Prunus americana). This small tree or shrub is found across much of North America. Accurate visual identification is important because many parts of the tree, other than the fruit’s outer flesh, contain compounds that can be toxic. Learning the distinct characteristics of the fruit, foliage, and structure ensures proper recognition, whether for appreciation or foraging.
Identifying the Fruit
The mature wild plum fruit is a reliable identification feature. It is significantly smaller than cultivated varieties, typically measuring about one inch (2.5 cm) in diameter. The fruit is a round to slightly oval drupe containing a single stone.
Coloration moves from green to yellow, orange, or bright red as the fruit ripens, often darkening to reddish-purple. A distinct visual cue is the glaucous coating, a thin, dusty, waxy layer covering the skin that easily rubs off. The skin is thick and often sour, contrasting with the sweeter, bright yellow flesh inside.
The interior holds a single, large, central pit. This stone is ovoid and flattened. The pit is usually semi-clingy, meaning the flesh does not easily separate from the stone. Wild plums ripen over the summer, ready for harvest from July through early autumn.
Recognizing the Leaves and Flowers
The leaves of the wild plum are alternate and simple. They are oblong or ovate (egg-shaped) with a sharply tapering tip, measuring between three and six inches in length.
The leaf margins feature sharp, fine teeth, often described as serrate or doubly serrate. The upper surface may appear wrinkled or slightly glossy, while the underside is typically paler and sometimes features fine hairs along the midrib.
Wild plum flowers appear early in the spring, often before the leaves have fully expanded. They are small, about one inch across, and consist of five rounded white petals. The blossoms grow in small clusters called umbels, with two to five flowers emerging from a single point.
Tree Structure and Growth Habit
The wild plum grows as a small, deciduous tree or a large, spreading shrub. It reaches a height of 10 to 25 feet. The overall growth habit is broad and spreading, sometimes resulting in an irregular crown.
The plant reproduces by root sprouts, which creates dense, often impenetrable thickets or colonies. The branches are thorny, possessing sharp spurs or lateral branchlets that can be two to three inches long.
The bark on younger stems is smooth, reddish-brown or gray, and marked with horizontal lenticels. As the tree matures, the bark darkens to a scaly, grayish-brown, developing irregular ridges that may peel or curl away from the trunk.