FREE INSTITUTE OF SCIENCE 



VEGETATION OF SOUTH FLORIDA 



The herbaceous layer of the hammocks consists of such plants as a fern, 

 Asplenium biscayanum (D. C. Eaton) A. A. Eaton, which grows on rocks 

 about the margins of sink holes. The small cane, Panicum latifolium L., is 

 common in Brickell Hammock, and two other grasses are conspicuous, viz., 

 Andropogon tenuispatheus Nash (5-15 dm. tall) and Paspalum ciliatifolium 

 Michx. Three sedges have been collected as part of the undergrowth, such as 

 an acaulescent one, Abilgaardia monostachya (L.) Vahl, Cyperus brunneus 

 Sw. and Scleria lithosperma (L.) Sw. Three euphorbiaceous plants are 

 found in Brickell Hammock, as far as the collections of the writer go: Cham- 

 aesyce conferta Small, C. gemella (Lag.) Small and C. hirta (L.) Millsp., to- 

 gether with Rivina humilis L., 3-7 dm. tall, and Piriqueta tomentosa 

 H. B. K. Finally, Afzelia pectinata (Pursh.) Kuntze (2-5 dm. tall), 

 Wedelia trilobata (L.) A. Hitchc. with creeping stems and branches and 

 Bidens leucantha (L.) Willd. naturalized from tropic America are elements 

 of the third, or herbaceous, layer of the forest. The herbaceous vegetation 

 cuts no important figure in Brickell Hammock. The plants that the 

 writer collected there are enumerated above. They do not form pure 

 associations, but are scattered beneath the shrubs and trees, here a species, 

 and there a species, so that with other peculiarities the broad-leaved 

 forests, or hammock vegetation, cannot be compared with the forests of tem- 

 perate regions. The subsidiary species are perched, as epiphytes, suspended in 

 air on the taller evergreen forest trees, while in temperate regions with periodic 

 leaf-fall, the herbs are on the ground and flower usually before the leaves have 

 developed fully. Two lianes are present in the sub-tropic forest which are 

 found also in the forests of broad-leaved trees in Pennsylvania, and elsewhere, 

 viz., the Virginia-creeper, Ampelopsis (Parthenocissus) quinquefolia (L.) 

 Planch, which extends to the Florida keys, Bermuda, Bahamas and Cuba, and 

 the poison-ivy, Rhus (Toxicodendron) radicans (L.) Kuntze, which extends 

 likewise to the Florida keys, Bermuda and Bahamas, but apparently is absent 

 in Cuba. With these few exceptions, the species are entirely different in the two 

 forest regions. 



At Immokalee, southwest of the Everglades, is a hammock covered with 

 hardwood trees, the surface of which is 11.5 meters (38 feet) above sea level 

 and the highest point between Ft. Myers and Brown's Store. Several other 

 hammocks in the Big Cypress wilderness have received local notice. One of 

 them is Deep Lake Hammock, reached by a trail running due south from 



