TRANSACTIONS OF WAGNER 



VEGETATION OF SOUTH FLORIDA 



and associations than can the systematist,* because he has been trained to 

 working with vegetation units rather than with species and the habitats of 

 species. The systematist usually emphasizes the peculiarities of land 

 surface classified by the geographer, but the plant geographer and ecologist 

 must insist on a classification based on the succession of vegetation; how 

 the formations and associations are related to each other, and what their 

 derivation has been from formations and associations that have preceded. 



The characterization of any plant formation and association does not 

 depend upon the enumeration of all the species that enter into association, 

 as some systematists of rather narrow view would have us believe, but 

 upon the forms which are dominant, which control, or which give physiog- 

 nomonic expression to the type of vegetation studied. It is possible to 

 describe a formation, or an association, by the mention of only one or two 

 species without a complete list of all the species that are found growing 

 together. This is an important principle and should be emphasized by 

 plant geographers. It might even happen that the ecologist might describe 

 a formation by mentioning correctly the dominant growth forms and their 

 growth habits, and yet he might, in the enumeration of the secondary 

 species, make mistakes in the identification of some of the plants. His 

 conclusions would not be vitiated by such mistakes, because he has ap- 

 proached the study from the standpoint of the vegetation as a whole and 

 not from the specific standpoint of the systematist. For example, the 

 phytogeographer describes the character of a pine forest, the growth of the 

 dominant pines, the formation of a crown and shade, the secondary species, 

 their suppression in the forest, the herbaceous plants of the forest flora. 

 His conclusions as to the character of the association of species may be 

 perfectly correct scientifically and of great value, as giving a general view 

 of the vegetation of a country, and yet, for the sake of argument, a number 

 of his determinations may be open to question. Of course, accuracy in 

 specific determinations is to be desired highly in all this kind of botanic 

 investigation, but the point which it is desired to emphasize is that vegeta- 

 tion can be described without mentioning specifically a single plant. 



An account will be given of the plant formations and associations, fol- 

 lowed by a discussion of the probable derivation and successions of the 

 various types of vegetation found at the southern end of the Florida pen- 

 insula. 



* Of course, there are always exceptions. 



