*The following is based on Gann, G.D., K.A. Bradley & S.W. Woodmansee. 2002. Rare Plants of South Florida: Their History, Conservation, and Restoration. The Institute for Regional Conservation: Miami. For updated species accounts, see Citation below. For the original text, follow the link in the Update field. If no Update field is displayed, then cite as the original publication.

Baccharis dioica Vahl

Hammock groundsel, Broombush Falsewillow

South Florida Status: Extirpated. Last collected in 1915 in Brickell Hammock.

Taxonomy: Dicotyledon; Asteraceae.

Habit: Shrub.

Distribution: Native to South Florida and the West Indies.

South Florida Distribution: Miami-Dade County.

South Florida Habitats: Rockland hammock edges.

Protection Status: Listed as endangered by FDACS.

Aids to Identification: This is the only species of Baccharis in South Florida with entire leaf margins. It has been confused with B. glomeruliflora and B. halimifolia, which sometimes have only a few obscure teeth.

References: Small, 1933a; Ledin, 1951; Long & Lakela, 1976; Cronquist, 1980; Correll & Correll, 1982; Nelson, 1996; Wunderlin, 1998; Coile, 2000.

Synonyms: None.

Historical Context: Nathaniel L. Britton first collected hammock groundsel in 1904 on “rocks south of Miami” (72, NY), presumably on the margins of Brickell Hammock. It was subsequently collected several times by John Kunkel Small and others at Brickell Hammock beginning in 1904 (1651, NY). Small made the last known collection of hammock groundsel at Brickell Hammock in 1915 (5449, NY). The apparent cause of extirpation was habitat destruction.

Recommendations: · Consider reintroduction to the edges of Brickell Hammock remnants at Alice Wainwright Park, Simpson Park, and Vizcaya Museum and Gardens. · Consider restoring rockland hammocks in the Brickell Hammock area and reintroducing hammock groundsel. · Review for listing by FNAI.