Three distinct height forms (short, medium, and tall) covering 

 a range of about 0.5 to 3 meters, have been widely recognized (Fig. 

 10). Within a natural marsh the tall form occurs along tidal creeks 

 and drainage channels, and the short form on flat or very gently slop- 

 ing areas away from the channels. The medixmi height form, when present, 

 usually occupies a band between the tall and short forms. It is uncer- 

 tain whether the differences in growth habit and productivity are due 

 to genetic factors or the result of local environmental conditions. 

 Earlier workers (Chapman, 1960; Stalter and Batson, 1969) suggested 

 that the stunted form is a genetic variety. More recent greenhouse 

 (Mooring, Cooper, and Seneca, 1971), biochemical (Shea, Warren, and 

 Niering, 1972), and field transplant studies (Woodhouse, Seneca, and 

 Broome, 1976) indicate that these differences are largely, if not alto- 

 gether, environmental. 



There are, however, distinct geographic populations of smooth cord- 

 grass. Seneca (1974) grew plants from seeds collected from Plum Island, 

 Massachusetts, to Port Aransas, Texas, under controlled conditions and 

 in the field at Snow's Cut, North Carolina, and found that there were 

 at least four groups differing in time of flowering, growth, reaction 

 to photoperiod, culm (stem), and leaf color. Flowering progressed from 

 north to south, growth was adapted to a progressively longer growing 

 season north to south, and basal culm diameter and leaf width increased 

 from north to south. 



Vegetative reproduction by extensive below-ground, hollow stems 

 (rhizomes) is the primary method of spreading in established stands. 

 Although seed production is usually limited in old dense stands, it 

 may be substantial in newly established stands and along margins such 

 as the borders of tidal creeks. Seeds are important in spreading the 

 plant into new areas and often contribute to thickening of open or 

 patchy stands. 



Smooth cordgrass has probably received more study and can be plant- 

 ed with better chance of success than any other coastal marsh species, 

 native to the United States. It is relatively easy to propagate and 

 quick to establish and spread. This grass tolerates inundation better 

 than any other salt marsh species on the Atlantic and gulf coasts. Con- 

 sequently, it is valuable in protecting the lower slope of spoil dis- 

 posal areas and eroding shorelines. 



(2) Saltmeadow Cordgrass {Spartina patens). This is a fine- 

 leaved grass, 15 to 80 centimeters in height, that occurs extensively 

 in the irregularly flooded high marsh zone all along the Atlantic 

 Coast (Figs. 9 and 10). In the absence of black needle rush, it re- 

 places smooth cordgrass at about the MHW level and forms dense mats 

 from MHW to the high spring or storm tide line. This grass often forms 

 a narrow band along the marsh edge but on gently sloping topography it 

 may cover a wide expanse and be mixed with saltgrass, patches of needle 

 rush, and other high marsh species. Saltmeadow cordgrass forms the 



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