Ambrosia hispida Pursh
Common Names: Sweet Bay, Bay Gerina, Bay Tansy, Wormwood, Soap Bush
Habit: Ambrosia hispida is an herbaceous perennial, growing along the ground rarely above 20 cm in height, and typically forming mats. The leaves are arranged oppositely, to 9 cm in length and pinnately compound, dividing 2 or 3 times creating a lacy appearance. The leaflets are lanceolate, with an acuminate leaf apex and deeply serrated leaf margin. The vegetative structures are covered with a hispid pubescence that gives the plant a light green to gray appearance.
The monoecious flowers are arranged in racemes of heads subtended an involucre made of 1 series of phyllaries. The actinomorphic flowers occur in the center of the head, each subtended by a bract. The staminate flowers have 5 sepals, 5 unfused stamens, and a non-functional ovary. The carpellate flowers have no perianth or stamens and a single superior ovary that becomes an achene at maturity. The achenes are covered with pubescence and tubercles.
Habitat: Ambrosia hispida grows in sandy dune areas along shorelines.
Distribution in Bahamas/Globally: Ambrosia hispida grows on all island groups within the Bahamian Archipelago as well as Florida, the entire Caribbean region, and Mexico south to northern South America.
Medicinal/Cultural/Economic usage: Ambrosia hispida is widely used in the Bahamas for a variety of illness categories including to treat colds and flu, gastrointestinal issues (increasing appetite, diarrhea, indigestion and vomiting), as well as dermatological problems (blisters and general skin irritation).
Elsewhere in the Caribbean it is used to treat worms and high blood pressure.