FREE INSTITUTE OF SCIENCE 



141 



VEGETATION OF SOUTH FLORIDA 



is not found on the Florida keys (see map). The geographic distribution of 

 the cypress hi South Florida is of unusual interest, as it throws considerable 

 light upon the succession of vegetation in the southern part of the peninsula. 

 The cypress, as far as the observations of the writer are concerned, exists in 

 areas of greater or less size, which may be differentiated by the following 

 descriptive terms: Cypress Swamp, Branch Cypress Swamp, Cypress Pond, 

 Cypress Bay, Cypress Head, Cypress scattered along river banks and ponds, 

 Cypress Scrub. 



Cypress Swamps. The areas denominated cypress swamps are true 

 swamps and covered with water the greater part of the time. The soil is 

 largely muck, but outcroppings of sand and rock occur. The trees are usually 

 large with conic, buttressed bases (Plate IX, Fig. i), and the knees are pointed 

 at the extremity. The influence of age is to cause the summit of the trees 

 to become flat-topped, and this flattening of the crown is in direct contrast to 

 the spire-shaped form, as first emphasized by William P. Wilson* in his study 

 of this species in Florida. Taxodium distichum (L.) L. C. Rich, is the domin- 

 ant tree, and associated with it are other trees, shrubs, lianes and ferns. The 

 trees are usually draped with Florida-moss. Other epiphytic orchids and 

 bromeliads grow upon the trunk and branches of the cypress trees. 

 Ecologically, a cypress swamp resembles one of broad-leaf deciduous trees 

 in the fact that the leaves of the cypress are deciduous and the swamp has a 

 more open sunlit character in the winter, when the cypress trees are leafless, 

 than in the summer, when the light-green foliage shades the subordinate vege- 

 tation beneath the dominant cypress trees. If one approaches a cypress 

 swamp through a pine forest in summer, the light greens of the cypress foliage 

 and the close set growth of the trees give an impression of gloom, but in winter 

 the swamp is more open and sunlit than the pine forest and the light-green color 

 of the mass of cypresses is changed to a grayish tone. 



Large cypress groves are located along the north, northeast and east 

 shores of Lake Okeechobee, where above Pelican Bay a ridge of fine silicious 

 sand runs along the shore of the lake. This ridge is several feet high and 

 varies from about 8 to 60 meters in width. Behind this ridge lies a dense 

 cypress swamp with majestic cypresses draped from top to bottom with fes- 

 toons of Spanish-moss, exhibiting the sylvan wonders of this primeval solitude. 



* Wilson, W. P.: The Production of Aerating Organs on the Roots of Swamp and other Plants, 

 Proc. Acad. Nat. Sci. of Phila., 1889: 67; The Bald Cypress. Forest Leaves II: no (1889). 



