NATURAL HISTORY

CAPE SABLE THOROUGHWORT } Chromolaena frustrata
FAMILY: Asteraceae

DESCRIPTION: The Cape Sable thoroughwort is a herbaceous perennial with slender stems (usually shorter than 3 feet); lance-shaped, aromatic leaves; and small clusters of lavender or blue flowers.

HABITAT: The thoroughwort lives grows in open-canopy habitats, including coastal berms and coastal rock barrens, and in semi-open to closed canopy habitats, including buttonwood forests and rockland hammocks.

RANGE: The historical range of this plant included mainland Monroe and Miami-Dade counties and 10 islands of the Florida Keys. It now occurs in the Everglades National Park and six islands in the Keys.

REPRODUCTION: The reproductive biology and genetics have not been studied.

LIFE CYCLE: The reproductive biology and genetics have not been studied.

FEEDING: This species, like most plants, gets its nutrition through photosynthesis.

THREATS: This plant is primarily threatened by the destruction of coastal habitat via human development and the ongoing threat of sea-level rise.

POPULATION TREND: In 2012 the Fish and Wildlife Service reported that 11 populations supporting approximately 1,500 to 2,500 plants occurred in near the southern tip of Cape Sable to Madeira Bay. In the Florida Keys, the plant had been extirpated from half the islands where it had formerly occurred. Although little is known about the long-term demographics or population trends of the Cape Sable thoroughwort, it appears that populations may experience declines due to the effects of hurricanes and storm surges, but the species may be able to rebound at affected sites within a few years.

 

Cape Sable thoroughwort photo   Keith A. Bradley