to the height differences between tall 

 creekbank S. alterni flora and the 

 stunted form on the more poorly 

 drained back marsh. The greater 

 oxygenation of pore waters by the 

 tides may also be the mechanism 

 responsible for the correlation 

 between creekbank S. alternif lora 

 production and tidal range reported by 

 Steever et al. (1976). On the high 

 marsh, however, the situation is even 

 more complex; no simple or direct 

 relationship has yet been found 

 between the distribution and abundance 

 of high marsh species and a particular 

 environmental variable. In spite of 

 some exciting advances in our under- 

 standing of marsh zonation and marsh 

 plants. Miller and Egler's (1950) 

 comment still seems appropriate: 



"One is tempted to feel that this 

 remarkable mosaic should be 

 interpreted in terms of ecologic 

 factors. If so, our present 

 knowledge is yet far from 

 sufficient. It is very likely 

 that contemporary concurrently 

 acting factors are only partly 

 responsible for present distri- 

 butions. In other words, simple 

 abnormal catastrophic factors may 

 have produced effects lasting 

 into the present; and general 

 past conditions may have been 

 such that the vegetation still 

 reflects them." 



The picture developed by Miller 

 and Egler (1950) from their work in 

 Connecticut is probably the m.ost 

 useful general model of vegetation on 

 the New England salt marshes. In 

 their studies of the Wequetequock- 

 Pawcatuck miarshes, Miller and Egler 

 found some 150 species of higher 

 plants distributed in five belts or 

 zones classified roughly according 

 to elevation. The number of species 

 was greater, and there were more 

 common species ( 80% occurrence in 



24 



test quadrats), on the upper borders 

 and slopes of the marsh than on the 

 lower portions or on the creekbanks 

 (Figure 16). Their general upland- 

 to-bay sequence consisted of a Panicum 

 virgatum Upper Border, a Juncus 

 qerardi Upper Slope, a Spartina patens 

 Lower Slope, and a Spartina alterni- 

 flora Lower Border. But Miller and 

 Egler also devoted considerable atten- 

 tion to the shallow pannes and pond 

 holes on the marsh surface. Many 

 pannes were characterized by stunted 

 Spartina alterniflora or by colorful 

 forbs such as Limonium carol inianum , 

 Triglochin maritima , Aster tenuifol- 

 ius , and Plantago decipiens which grew 

 around their edges. Toward the inner 

 portions of the pannes, evaporation 

 and poor drainage produced areas with 

 salt accumulation that were colonized 

 by succulents such as Sal i corn i a 

 europea or remained unvegetated. Pond 

 holes with the submerged macrophyte, 

 Ruppia maritima , and various algae 

 occurred in other areas. 



The extent of these zones varies 

 considerably in individual marshes. 

 In general, the Panicum Upper Border 

 and the Juncus Upper Slope are narrow 

 and separate the marsh proper from 

 upland trees and shrubs. The high 

 marsh, consisting of Spartina patens , 

 Distichlis spicata , and short S. 

 alterniflora in various combinations 

 of pure stands and mixtures, appears 

 to comprise the largest area of most 

 unfilled marshes. The regularly 

 flooded or low marsh consisting of the 

 tall form of S. alterniflora often 

 amounts to 10% to 20% of the area of 

 emergent grasses (Table 4). In the 

 past, the coverage of the high marsh 

 S. patens , Juncus , and D istichlis may 

 have been even greater. In comparing 

 their more recent marsh surveys on 

 Long Island with those made 34 years 

 earlier by Taylor (1938), O'Connor and 

 Terry (1972) noted that: 



"Taylor described Spartina patens 

 as 'by far the most common grass 



