TRANSACTIONS OF WAGNER 
VEGETATION OF SOUTH FLORIDA 
76 
and southern ends of Key Largo are low and covered with mangroves. On this 
island, the low salt flats are controlled by the black-mangrove, Avicennia 
nitida Jacq., and wherever a salt channel is reached, such a channel is 
lined with red-mangroves. Long Key has a large reéntrant bay at its northern 
end with its shore lined with this type of littoral swamp vegetation. My notes 
of June, 1912, continue the observations from Long Key, which was visited in 
December, тото. Grassy Key is mangrove fringed and has mangrove flats. 
The lower end of Key Vaca is a mangrove flat, while Little Duck Key is almost 
entirely a flat covered with mangroves. Bahia Honda Key has flat mangrove 
areas and salt lagoons with islands of these trees raised on their stilt-like 
roots. Similar flats and fringing mangrove swamps are found on Summer- 
land, Big Pine, Cudjoe, Sugar Loaf, Saddle Bunch, Big Coppit keys, followed 
by a succession of low mangrove islands around Rockland and Boca Chica 
keys, while Key West is partly fringed with a dense, impenetrable thicket of 
low mangrove trees not over 3-3.5 meters (10-12 feet) tall. 
The south shore of the peninsula of Florida, touching the Bay of Florida, 
as far as Flamingo, is bordered by a dense and wide mangrove thicket, which 
extends north until it blends with the coastal prairie-everglade. Here the 
thicket begins to thin out and the trees become scattered.* These scattered 
trees extend some distance back into the coastal prairie-everglade where they 
become smaller, lower (not over 1 meter tall), and reduced to a few leafy branches 
raised on widely extended prop roots. (Plate II, Fig. 1.) The leaves assume 
here a yellowish-green color. Here the trees grow in fresh water and their 
presence is due to survival from a time when the mangrove swamp covered all 
of the southern end of the peninsula. As the dry-land conditions became more 
pronounced, the northern edge of the coastal swamp was invaded by prairie- 
everglade vegetation. The mangrove trees were gradually suppressed until 
surrounded with grass and sedge vegetation and almost completely choked by 
it, a few low, scattered mangrove trees of a yellowish-green color remaining 
under the stress of the competition of the everglade-prairie plants. (Plate 
II, Fig. 1.) 
The uncertainty as to the outline of White Water Bay, Ponce de Leon Bay 
and the Bay of Ten Thousand Islands is on account of the islands of mangrove 
* Compare the accounts of Harper, R. M.: Report on Peat, Third Annual Report Florida Geo- 
logical Survey, 228, 233, 327; Tramping and Camping on the southeastern Rim of the Everglades 
Florida Review, 4; 154-155. 1910. 
