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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



grove swamp and fresh-water prairie the brackish 

 marsh zone is very wide. Dwarfed and scattered 

 specimens of Rhizophora mangle L. grow inland 

 along the rivers running from the Everglades and 

 in the wet prairies where the water has little or 

 no salt content. There it may be associated with 

 Cladium jamaicensis Crantz, sawgi-ass, Typha 

 domingensis Pers., cattail, Sagiftaria lancifolia L., 

 arrowhead, Acrostichum danaeae folium Langsd. & 

 Fisch., leather fern, and Annona glabra L., custard- 

 apple. Similarly, where large rivers flow into the 

 Gulf there are along the estuaries wide areas of 

 brackish marshes transitional between the coastal 

 salt marshes and fresh-water marshes and swamps. 

 Where salt marsh abuts upon pineland, as in the 

 Tampa Bay region, a difference of 30 centimeters 

 in ground level brings an abrupt change in the 

 physiognomy of the vegetation. The narrow zone 

 of transition is often marked by a thicket of 

 Myrica cerifera L., waxmyrtle, several species of 

 Baccharis, groundselbushes, and Sabal palmetto 

 (Walt.) Todd., cabbage palm. 



There are no salt marshes on the Cuban Gulf 

 coast. Many of the American salt-marsh species, 

 however, grow mixed with tropical species in the 

 mangrove swamps or on low-lying beaches. Al- 

 though the coastal vegetation of Mexico is poorly 

 known, the same relationship probably exists be- 

 tween salt-marsh plants and mangroves from 

 southern Tamaulipas to Yucatan as on the south- 

 ern Gulf coast of Florida and Cuba. The Yucatan 

 coast possesses such salt-marsh or salt-flat plants 

 as Distichlis, Monanthochloe, Spartina, Sporobolim, 

 Fimbristylis, Philoxerus, Salicornia, Suaeda, Batis, 

 Sesuvium, Baccharis, and Borrichia, as well as the 

 mangroves and many associated plants. 



Salt-marsh plants live under most difficult con- 

 ditions: high salt content in the soil solution, poor 

 aeration resulting from the poor drainage, recur- 

 rent submersion and exposure, and full insolation. 

 Only species with a wide range of tolerance to 

 these conditions can survive. Marsh height, tidal 

 submergence, and salinity of the soil solution 

 appear to be the most important factors in pro- 

 ducing zonation in salt marshes. Spartina alterni- 

 flora Loisel. withstands the deepest flooding. It 

 is also, with Distichlis spicata, Juncus roemerianus , 

 Batis, Salicornia, and the other succulent halo- 

 phytes, apparently the most salt-resistant. Uphof 

 (1941) has reviewed the literature on halophytes. 



SAND-STRAND VEGETATION 



The flowering plants of sandy shores are not 

 strictly aquatic, yet they are too conspicuous and 

 too abundant along Gulf coasts to omit from this 

 treatment. Most thoroughly studied and de- 

 scribed are the Florida beaches. Webber (1898), 

 MUlspaugh (1907), Harshberger (1914), Bowman 

 (1918), Simpson (1920), Harper (1927), Davis 

 (1940, 1942, 1943), and Kurz (1942) have de- 

 scribed the beach vegetation of the Florida Gulf 

 coast. Strand vegetation along the northern Gulf 

 coast has been treated by Mohr (1901), Lloyd 

 and Tracy (1901), Cocks (1907), Lowe (1921), 

 and Fenfound and O'Neill (1934). Except for the 

 addition of more tropical species and the dropping 

 out of more temperate species, the strand flora of 

 Yucatan, Cuba, and other West Indian islands is 

 very similar to that of southern Florida. This 

 similarity is readily apparent from the descriptions 

 of the beach vegetation of Yucatan (Bequaert 

 1933; Lundell 1934), Cuba (Uphof 1924; Seifriz 

 1943), Puerto Rico (Cook and Gleason 1928), and 

 the Virgin Islands (B0rgesen 1909; Raunkiaer, 

 1934). Beach and dune vegetation along the At- 

 lantic Coast of North America is described by 

 Kearney (1900, 1901), Harshberger (1900), and 

 Conard (1935). General treatments of strand 

 vegetation in other parts of the world can be 

 found in Schimper (1891), Schimper and Faber 

 (1935), and Warming (1909). 



Sandy shores of the Gulf coast show as definite 

 a zonation as salt marshes and mangrove swamps. 

 Costing (1945) attributes this zonation to the 

 tolerance to salt spray of the various coastal dune 

 plants. The community is definitely a halophytic 

 one. Due to vigorous wave action few plants 

 survive on the lower beach. The pioneers of wet 

 or shifting saline sands are found on the upper 

 beach and the fore dunes. In the Tampa Bay 

 region of the Florida coast the most abundant 

 strand species are Sesuvium portulacastrum L., 

 sea-purslane, Sporobolus virginicus (L.) Kunth, 

 drop-seed, Atriplex arenaria Nutt., beach orach, 

 Cakile edentula (Bigel.) Hook., sea-rocket, Helio- 

 tropium curassavicum L., seaside heliotrope, Phi- 

 loxerus vermicularis (L.) R. Br., beach-carpet, Iva 

 imbricata Walt., beach-elder, Uniola paniculata 

 L., sea-oats, Euphorbia buxifolia Lam. and E. 

 ammannioides HBK., spurges, Ipomoea pes- 

 caprae (L.) Sweet and /. littoralis (L.) Boiss., 



