THE MOSQUITOES OF THE SOUTHEASTERN STATES 27 
gates so that the marshes become dry eliminates much breeding of the 
sand fly (Culicoides) as well as of the mosquito. It is probable that 
this practice can be combined with ditching in other sections where 
the sand fly is a serious problem. 
In the southern half of Florida, where Aedes taeniorhynchus is the 
predominant salt-marsh mosquito, the marsh vegetation is dominated 
by growths of several species of mangrove. This presents special 
problems for the mosquito-control organization (pl. 4, B; fig. 8), 
as the mangrove forms dense forests through which it is necessary 
to cut rights-of-way 15 to 25 feet wide before ditches can be dug. 
Dynamite ditching has been employed in such marshes and compares 
favorably in cost with hand labor. 
Fieurn 8.—Red mangrove (Rhizophora mangle) in a Florida salt marsh, show- 
ing the dense growth and characteristically divided base. 
Another difficult problem is encountered in certain areas where the 
marshes border more or less landlocked bodies of water in which there 
is ordinarily little tidal range. Strong wind tides may cause a flood- 
ing of these marshes, and continuous winds may hold the water there 
long enough for a brood of mosquitoes to develop even though the 
marsh is thoroughly ditched. To meet this problem it has been pro- 
posed to dike such areas and remove the floodwaters when necessary 
by means of pumps. A program along this line, combining mosquito 
and sand fiy control, was begun in Saint Lucie County, Fla., in 1936. 
The control work against salt-marsh mosquitoes in the North 
Atlantic States has been criticized as unnecessarily destroying the 
feeding and breeding grounds of wildlife. It is believed that many 
of the deeper ponds, as well as the plant species that serve as food, 
can be saved without detriment to the antimosquito work. If the 
ponds are of value as feeding and resting grounds for wild fowl, 
the ditches may be diverted or, if they are run into the ponds, a 
