Tropical soda apple is native to Brazil, Paraguay, Uruguay, and Argentina [70,75]. It has been introduced in the southeastern United States, Africa, India, Nepal [70,75], and parts of tropical Asia . It is considered a common weed in Honduras, Mexico, and West Indies ; however, it is unclear whether it is native or nonnative in these countries. It is expected to spread to other subtropical areas outside its current range .
In the United States, tropical soda apple is most common in Florida and has been reported in Texas, Arkansas, Louisiana, Mississippi, Alabama, Georgia, South Carolina, North Carolina, Texas, Tennessee, Pennsylvania [59,71,90,96], and Puerto Rico [13,71]. By 2002, researchers reported that tropical soda apple may have been eradicated from Louisiana, Tennessee, and Pennsylvania , so its occurrence in these states is uncertain. By 2007, many of the small infestations of tropical soda apple had been eliminated in Mississippi , so its spread may be on the decline in that state. Tropical soda apple was first collected in the United States in southern Florida between 1987 and 1988 and spread to other southeastern and mid-Atlantic states soon after [70,108]. Herbaria records show that it had spread to at least one county (Jasper County) in Texas by 2004 . Tropical soda apple has the potential to invade the remaining southern states and some central states including Colorado, Kansas, and Illinois . It may be able to overwinter as a perennial at or below 33° N latitude and may persist as an annual in cooler areas . Plants Database provides a distributional map of tropical soda apple in the United States.
Tropical soda apple's introduction likely occurred through the unintentional movement of plants or seeds from South America, although its exact means of introduction is unclear . The spread of tropical soda apple within Florida and to other southeastern states has been facilitated by movement of cattle, pasture grasses, and composted manure from infested areas [71,108].
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