The American plum tree is a part of the rose family, a family that also includes the cherry and the apple tree. The American plum grows wild throughout much of the United States, from the upper Midwest south to the Texas coast and east to the Atlantic Coast as far north as the middle of New England. While you can use your eyes to identify this tree by its features, your nose can come in handy as well.
Consider the tree's habitat. American plum trees normally grow by the side of a road, along the edges of fields and along fence rows. Plums also have the ability to grow in large numbers, forming thickets.
Check the tree's size. American plum trees typically never exceed 30 feet and average about 20 feet tall. The spreading crown often makes this tree wider than it is tall.
Distinguish a plum by its tapered oblong leaves. The edges of these leaves will have teeth along them, and the leaves may feel hairy. In the fall these green leaves fade, in most cases to a chartreuse color, before falling from the plum tree as winter arrives.
Smell the flowers of the tree and notice whether they possess a pungent aroma. American plum trees flowers also emerge even before the leaves are on the branches. These white flowers will be an inch across and grow in clusters of between two to five.
Identify an American plum tree by the plums themselves. Plums are round, an inch long and start out a light-green shade before turning reddish. The insides of a ripe American plum are yellow and tart, but when they are over ripe, they have a sweetness to them.
Recognize an American plum tree from the thick twigs in the higher branches. These branches in the canopy of the plum tree will have thorns on them as well. The mature plum tree has scaly bark that is a gray-brown color; the younger plums have shiny brown bark that feels smooth.