the plants that, at present, appear useful in coastal marsh creation. 

 The small number of these plants is due to the saline conditions pre- 

 vailing in most coastal marshes, the rigorous conditions during estab- 

 lishment, the difficulties encountered in propagating some species, the 

 lack of information available on others, and the secondary role a number 

 of the plants play in stabilization and productivity. A great deal is 

 known about where and under what conditions many marsh plants grow. 

 Interest in planting them is of recent origin and planting requirements 

 are known for only a few. More species are likely to be found useful 

 in the future. 



For marsh- pi anting purposes, the coasts of the continental United 

 States are divided into tlie Atlantic, Peninsular Florida, Gulf of 

 Mexico, North Pacific, South, Pacific, and the Great Lakes, The Atlan- 

 tic coast extends from the Canadian border to sx)uth of Jacksonville, 

 Florida, where it grades into the Florida segment. The peninsular 

 Florida coast begins here where mangroves start to invade salt marsh, 

 extending around the peninsular Florida Keys to about the Suwannee 

 River on the Gulf of Mexico. The gulf coast is a long and rather vari- 

 able stretch extending from tke Suwannee River around the gulf to the 

 Mexican border. The Pacific coast is divided into the North Pacific 

 section from about northern California to the Canadian border; the 

 South Pacific section extends from north of San Francisco southward 

 to Mexico. The Great Lakes coasts include the sheltered or semi- 

 sheltered bays and inlets on all of the Great Lakes. 



a. Atlantic Coast . This region encompasses a wide climatic range 

 and a variety of secondary marsh species; however, the same species are 

 planted throughout the region. 



(1) Smooth Cordgrass {Spavtina attemaflord) . Thig is the 

 dominant flowering plant in the regularly flooded intertidal zone along 

 the Atlantic coast from Newfoundland to about central Florida (Fig. 9) . 

 These marshes are essentially pure stands of smooth cordgrass. This 

 grass is well adapted to sea strength salinity (35 parts per thousand), 

 excreting salt through salt glands in its leaves. The plant is also 

 well adapted to the anaerobic substrates characteristic of most salt 

 marshes. Its oxygen transport system consists of hollow, air-filled 

 tissue, extending from openings in the leaves to the roots and rhi- 

 zomes (Teal and Kanwisher, 1966; Anderson, 1974). Thus, oxygen reaches 

 the below-ground tissues in anaerobic substrates. This grass can grow 

 in a wide range of substrates from coarse sands to silty clays. Al- 

 though dominant in regularly flooded, saline habitats, it is not re- 

 stricted to these areas. It usually attains maximum growth under 

 lower salinities (10 to 20 parts per thousand). The grass will grow 

 and reproduce normally under freshwater conditions but is subject to 

 increasing competition from other species as salinity declines (Wood- 

 house, Seneca, and Broome, 1972, 1974). 



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