Chris Evans, River to River CWMA

White Mulberry

Morus alba L.
Mulberry family (Moraceae)

Origin: China

Background
White mulberry was introduced to the U.S. during colonial times for the purpose of establishing a silkworm industry.

Distribution and Habitat
White mulberry is widespread in the U.S., occurring in every state of the lower 48 except for Nevada. It invades old fields, urban lots, roadsides, forest edges, and other disturbed areas.

Ecological Threat
White mulberry invades forest edges and disturbed forests and open areas, displacing native species. It is slowly outcompeting and replacing native red mulberry (Morus rubra) through hybridization and possibly through transmission of a harmful root disease.

Description and Biology

• Plant: deciduous tree, 30-50 ft. tall; young bark, inner bark and bark along the roots is bright orange; older bark is grey with narrow irregular fissures; bark splits easily; stems are glabrous to pubescent, not thorny.
• Leaves: alternate, simple, glossy above, toothed, unlobed or lobed with one or many, sometimes deep lobes; upper leaf surface glossy, glabrous or slightly scabrous; lower leaf surface glabrous, or slightly pubescent on the veins and in the vein axils only.
• Flowers, fruits and seeds: flowers are produced in Spring; male and female flowers are on separate plants; male flowers are small, green and occur in 1-2 in. long catkins; female flowers are inconspicuous and crowded in short spikes; fruits form from female flowers; fruits are multiple-seeded berries that range in color from black to pink to white when ripe; contain abundant seed--a single tree is estimated to produce twenty million seeds!
• Spreads: by seed which is consumed by wildlife and deposited in new locations.
• Look-alikes: may be confused with native red mulberry (Morus rubra) which has larger leaves that are dull and rough; basswood (Tilia sp.) with unlobed leaves and flowers and fruits on leaf-like bracts; sassafras (Sassafras albidum) with smooth-margined lobed to unlobed leaves; and paper mulberry (Broussonetia papyrifera) with leaves densely gray-pubescent.

John Cardina, The Ohio State Univ.

Bill Johnson

Prevention and Control
White mulberry seedlings can be pulled by hand. Otherwise, cut the tree and grind the stump or paint the cut surface with a systemic herbicide like glyphosate or girdle the tree (see Control Options).

Native Alternatives
Red maple (Acer rubrum), hackberry (Celtis occidentalis), black gum (Nyssa sylvatica) and sassafras (Sassafras albidum).