Mulberry Morus rubra
The red mulberry (Morus rubra) is a medium-sized deciduous tree native to Alabama and found throughout the state in rich hardwood forests, stream bottoms, floodplains, and woodland edges. Recognized by its broad leaves, milky sap, and clusters of dark purple to black fruits, red mulberry is one of Alabama’s most valuable native wildlife trees. The species provides abundant food resources for birds, mammals, and pollinators while contributing to the biodiversity and structure of moist forest ecosystems.
Taxonomy
- Family: Moraceae
- Genus: Morus
- Species: Morus rubra
- Common names: Red mulberry, mulberry, common mulberry
Identification & Morphology
Red mulberry is a medium-sized deciduous tree that typically grows 30 to 60 feet tall with a broad, rounded crown. The trunk is often short and may divide into several large limbs, particularly in open-grown trees.
The bark is gray-brown with narrow ridges and irregular furrows that become more pronounced with age. Young twigs are slender and contain a milky sap characteristic of the mulberry family.
Leaves are alternate, simple, and highly variable in shape. They are often broadly heart-shaped but may be unlobed, mitten-shaped, or deeply lobed on the same tree. Leaves generally measure 3 to 8 inches long and have serrated margins with a rough upper surface.
Flowers appear in spring as slender catkins. Male and female flowers are usually borne on separate catkins and may occur on the same or different trees. Fruits develop from multiple flowers fused together into a blackberry-like cluster known as a multiple fruit.
The fruits ripen from red to dark purple or nearly black during late spring and early summer. Mature fruits are sweet, juicy, and highly attractive to wildlife. The species can often be identified during fruiting season by heavy crops of dark berries beneath the canopy.
Ecological Role
Red mulberry is among the most important wildlife food plants in Alabama forests. The fruits are consumed by numerous songbirds, including thrushes, catbirds, mockingbirds, tanagers, orioles, and woodpeckers. Wild turkey, raccoon, opossum, foxes, squirrels, and other mammals also readily consume the fruit.
Because fruits ripen during late spring and early summer, red mulberry provides an important seasonal food source when many other native trees have not yet produced fruit. Wildlife often disperses seeds considerable distances after consuming the berries.
The leaves support a variety of native insects, including several moth and butterfly species. Flowers provide resources for pollinating insects, while the tree itself contributes to forest structure by creating nesting and perching opportunities for birds.
In riparian forests and mesic hardwood systems, red mulberry contributes to nutrient cycling, understory diversity, and wildlife habitat complexity. The species frequently occurs as a midstory tree beneath larger hardwoods where it enhances overall biodiversity.
Habitat & Site Conditions
Red mulberry occurs throughout Alabama and is most commonly found in rich bottomlands, floodplain forests, stream terraces, moist coves, woodland edges, and fertile upland hardwood forests.
The species performs best on deep, moist, well-drained soils rich in organic matter. Although it tolerates occasional flooding, it generally grows best in sites that remain moist but not continuously saturated.
Red mulberry is considered moderately shade-tolerant and commonly develops beneath larger canopy species before reaching the midstory or lower canopy. In Alabama, it is often associated with American beech, tulip poplar, black gum, sweetgum, sycamore, oaks, hickories, and maples.
The species prefers full sun to partial shade and is particularly abundant in areas where forest disturbances create moderate canopy openings.
Research & Conservation Considerations
Red mulberry remains widespread throughout Alabama; however, throughout parts of its native range it faces pressure from hybridization with the introduced white mulberry (Morus alba). White mulberry was introduced from Asia during the colonial period to support silkworm production and now occurs widely across the eastern United States.
Conservation efforts in some regions focus on maintaining genetically pure populations of native red mulberry and reducing hybridization where feasible. Native red mulberry can generally be distinguished by its rough leaf surface and larger fruits, although identification may become difficult where hybrid populations occur.
Historically, red mulberry wood was used for fence posts, barrels, furniture, and specialty wood products because of its strength and natural durability. Native peoples and early settlers also valued the fruits for fresh consumption and preserves.
Current research involving red mulberry focuses on forest ecology, wildlife habitat enhancement, native plant conservation, and the effects of hybridization with non-native mulberry species. Because of its exceptional wildlife value and adaptability to a variety of forest settings, red mulberry remains an important component of Alabama’s native hardwood ecosystems.