TRANSACTIONS OF WAGNER 
132 
3 VEGETATION OF SOUTH FLORIDA 
prairie along the Florida East Coast Railroad south of Detroit in circular forms 
of large and small size surrounded with grass and sedge vegetation. In these 
hammocks the palmetto is conspicuous, as well as other sclerophyllous plants, 
such as Cerothamnus (Myrica) ceriferus (L.) Small. These hammocks be- 
come more common some distance southward, and there the prairie is 
dotted with them. 
Live-Oak-Palmetto Hammock Formation.—The live-oak-palmetto hammock 
is a type of river hammock occurring in drier soil. The live-oaks, Quercus 
virginiana Mill, have spreading branches and form the dominant growth. Be- 
tween these oaks and rising to an equal height the palmetto trees are scattered, 
or sprinkled through the hammock. Sometimes the palmetto trees are more 
abundant and the hammock approaches in ecologic character the type previ- 
ously described. Where the palmetto trees are scanty the live-oak-palmetto 
hammock merges insensibly into one consisting of live-oaks. The branches 
of the live-oaks are loaded with epiphytes of various sorts, but one of the most 
conspicuous is the small green fern, Polypodium polypodioides (L.) A. S. 
Hitchc. (=P. incanum Sw.). Another common epiphyte is Tillandsia tenui- 
folia L., with wiry leaves of a reddish color, that grows in dense tufts on the 
limbs of the oak trees. The gray, flowing beards of the Florida moss, Den- 
dropogon (Tillandsia) usneoides (L.) Raf., add to the gloom of such forests, 
which drip water in rainy weather. The prevailing gray color of the forest is 
heightened by the gray lichens that cover the bark of the large oak trees. 
Live-Oak Hammock Formation.—This type of hammock is one of the series 
beginning with the palmetto river hammock. The series consist of palmetto 
hammock, live-oak-palmetto hammock, live-oak hammock. The live-oak ham- 
mock is comparatively open, as far as the undergrowth is concerned, but the 
abundance of epiphytes and the long festoons of the Spanish-moss fill up the 
available light space, so that the open, orchard-like character of the forest does 
not impress the observer. When this type of vegetation blends with certain 
elements of the pineland, we have another type of formation, which perhaps 
should be included with the dry hammock series, on the one hand, or with a 
modified type of pine forest on the other. Perhaps it should be considered 
distinct. 
Oak-Saw-Palmetio Sclerophyllous Forest Formation.—Here the live-oak 
trees are of smaller size and more scattered, although the epiphytic growth on 
the oaks is as abundant as in the preceding type. This formation, however, 
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