Family: Solanaceae (Potato Family)
Duration and Habit: Perennial Subshrub
Upright, thorny perennial subshrub or shrub, 3 to 6 feet (1 to 2 m) in height, with leaves shaped like oak leaves, clusters of tiny white flowers, and green-to-yellow golf-ball size fruit. Fruit sweet smelling and attractive to livestock and wildlife. Remains green over winter in most southern locations.
Ecological Threat: Tropical soda apple is on the Federal Noxious Weed List (UUSDA NRCS). It reduces biological diversity in natural areas by displacing native plants and disrupting ecological integrity. Plant prickles can restrict wildlife grazing and create a physical barrier to animals, preventing movement through infested areas. It contains solasodine, which is poisonous to humans. This invader also serves as a host for viruses that infect important vegetable crops.
Biology & Spread: The sweet smell of the fruit attracts livestock and wildlife that eat and spread the seed. Each plant can produce approximately 50,000 seeds. It reproduces primarily by seed, but can also spread by roots.
History: Native to Argentina and Brazil and introduced into Florida in the 1980s. No known use. A Federal listed noxious weed with an eradication program underway.
U.S. Habitat: Located in open semi-shaded areas such as pastures, ditch banks, roadsides, recreational areas, citrus groves, sugar cane fields, and wet areas of rangeland. It is typically found in soils that are poorly drained and sandy, but cannot survive extremely wet soils.
U.S. Nativity: Introduced to U.S.
Native Origin: Southern Brazil, Paraguay
U.S. Present: AL, FL, GA, MS, NC, PA, SC, TN
Resembles horsenettle (Solanum carolinense).
Manual- Mowing can be used to stop fruit production; wear gloves when handling plants
Chemical- It can be effectively controlled using any of several readily available general use herbicides such as glyphosate, imazapyr or triclopyr. Collect and destroy fruit to prevent reestablishment. Follow label and state requirements.
Biological control: The bacterial pathogen Ralstonia solanacearum (E. F. Smith) Yabuuchi is effective in causing plants to wilt and die as seen in the photo to the right.
Miller, J.H. 2003. Nonnative invasive plants of southern forests: a field guide for identification and control. Gen. Tech. Rep. SRS-62. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 93 pp (USDA SRS).
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