study, little was known about establishing new stands of this plant, 

 although natural stands had been investigated extensively for a long time. 

 Marsh planting of a closely related species, S. townsendii H. £ J. Groves 

 (Ranwell, 1967) has been practiced in northern Europe primarily for the 

 purposes of land reclamation. 



2. Biology of Spartina alterniflora . 



Spartina alterniflora is the dominant flowering plant in regularly 

 flooded intertidal marshes along the Atlantic and Gulf coasts from 

 Newfoundland to Texas. These low marshes are almost pure stands of S. 

 alterniflora, and constitute what is generally considered the most valua- 

 ble type of estuarine marsh. Although the shoots of the grass are often 

 covered with algae that may be grazed by the salt marsh periwinkle, 

 Littorina irrorata (Say), only a small part of the annual production of 

 the grass itself is consumed by other organisms (mainly insects and birds) 

 while the plant is living. After the aboveground parts of the plant die 

 and fragment, small suspended particles called detritus with associated 

 decomposing microorganisms are exported into the estuary. The detritus 

 is utilized by fish and invertebrate animals which may be permanent or 

 temporary inhabitants of the estuary. In estuaries where high turbidity 

 reduces light penetration which lowers phytoplankton production, marsh 

 grasses account for most of the primary production by the system. 



Primary production of marshes dominated by S. alterniflora varies 

 with latitude and also within any given marsh. An increasing annual 

 production trend from north to south has been described by the combined 

 work of Good (1965) and Durand and Nadeau (1972) in New Jersey, Keefe and 

 Boynton (1973) in Maryland-Virginia, Stroud and Cooper (1968) and Williams 

 and Murdoch (1969) in North Carolina, Smally (1959) in Georgia, and Kirby 

 (1971) in Louisiana. This production trend may be partially due to a 

 latitudinal gradient of increasing length of growing season from north to 

 south. Production also varies a great deal within a particular marsh due 

 to height of the grass which varies from about 0.5 to 3.0 meters. Three 

 distinct height forms described as short, medium, and tall are generally 

 recognized (Teal, 1962; Adams, 1963; Stroud and Cooper, 1968). Based on 

 their study in Brunswick County, North Carolina, Stroud and Cooper reported 

 differences in annual net production of the short, medium, and tall height 

 forms as 280, 471, and 1,563 grams per square meter per year, respectively. 



There is some disagreement about whether the difference in growth 

 habit and production among the height forms is due to genetic differences 

 between the short and tall height forms or if the size difference is the 

 result of environmental factors. Chapman (1960) suggests that the stunted 

 S. alterniflora is actually a genetic variety which is inherently smaller 

 than the closely associated taller form. Data reported by Stalter and 

 Batson (1969) from a transplant experiment suggest that there are two forms 

 of S. alterniflora, one which is inherently dwarf and one which is 

 inherently tall. However, the period over which the transplants were 

 observed was too short to be conclusive. The most obvious environmental 

 factor to which zonation in salt marshes may be related is the relationship 



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