The red mulberry tree (Morus rubra) is a species that occurs from New Jersey westward into the Great Plains and into much of the south from Texas to Florida. The tree produces a tasty edible berry often utilized in jellies, jams and preserves. Red mulberry has polymorphic leaves; this means that on the same tree, often on the very same limbs, the leaves can have different shapes. Identifying the red mulberry leaves requires some knowledge of these shapes and other aspects of this foliage.
Look for leaves that come in multiple shapes on one tree. Among the shapes you will encounter are leaves that are broadly oval, as well as two-lobed leaves that look like a child's winter mitten's silhouette. These leaves may accompany leaves that possess multiple lobes. The leaves of different shapes can develop next to one another, growing alternately on the twigs of the tree.
Measure the length and the width of the leaves on a red mulberry tree. The length will vary, with some leaves as short as 3 inches and others as long as 7 inches. The width is also variable, ranging between 2 and 5 inches.
Examine the leaves for pointed lobes and/or tips. Red mulberry differs from its close relative, a non-native species to the United States known as white mulberry, by having a pointy tip on each leaf or on each leaf lobe. The lobes and tips on the white mulberry leaf are typically blunt and/or rounded. Note that three main veins will radiate from the point where the petiole (stem) attaches to a red mulberry leaf. A network of veins will then radiate off these major veins outward to the edges of the leaf.
Inspect the margins of the red mulberry leaf for a series of coarse teeth. The serrations will be all along the edges of the red mulberry foliage, except for where the lobed leaves indent inward. In addition, you should note that the upper sides of the red mulberry leaf would feel rough, almost the same as a piece of sandpaper, says the Ohio Department of Natural Resources website. Conversely, the underneath half of the leaf will be pubescent, covered with fine hairs.
Observe the colors of red mulberry leaves. The leaves appear to be a shiny green in spring and summer. In autumn, red mulberry leaves generally take on a yellowish tint before the tree sheds all of its foliage long before winter.