Linthurst (1977) found that cordgrass in Maine grew at elevations of 7.6 feet 

 (2.3 to 3.0 m; creek bank) and 8 to 9 feet (2.4 to 2.8 m; higher marsh) above 

 mean low water (MLW) . (In Maine, mean high water approximates 10.5 feet, 3.2 

 m, and mean low water 0.0 feet.) Generally, creek bank cordgrass reaches a 

 maximum height of 4 to 6 feet (1 to 2 m) at peak standing crop (July and 

 August). Farther into the marsh, as elevation increases, cordgrass may become 

 dwarfed, attaining 0.5 (0.25 m) to 1 feet (0.5 m) in height. The following 

 species occassionally are found in association with cordgrass in Maine: salt 

 marsh aster ( Aster novibelgii ) , sea lavender, ( Limonium nashii ) , saltwort 

 ( Salicornia europea ) and salt hay. 



Maine salt marshes are dominated by high intertidal marsh (salt meadows). 

 Salt meadows (salt hay and spike grass Distichlis spicta ) grow at elevations 

 that are irregularly flooded by tides (exceed the mean high tide level). 

 Linthurst (1977) found that salt hay grew at an elevation of about 9.8 feet (3 

 m) above MLW. Species that may associate with salt hay are: salt marsh 

 aster, orach (Atriplex patula hastata), seaside gerardia ( Gerardia maritima ) , 

 salt marsh pink (Stellaria stellaris), marsh alder ( Iva f rutescens ) , panic 

 grass (Panicum virgatum ) , sea-meadow grass ( Puccinellia sp.), silverweed 

 ( Potentilla quinquefolia ) , sea lavender, saltwort, salt marsh cordgrass, black 

 rush, and arrowgrass (Triglochin maritima). 



Salt hay grows from 6 inches to 2.4 feet (15 to 75 cm) in height in dense 

 yellowish gieen mats and often resembles a meadow with swirls or "cowlicks." 

 Spike grass is darker green and grows in association with salt hay but may 

 occur in dense, erect, pure stands. 



The black rush coiranunity often is found immediately above the salt haymeadow. 

 In Maine, black rush grows from 10 to 13 feet (3 to 4 m) above MLW on creek 

 banks and on high marshes (Linthurst 1977). This area defines the upper slope 

 of the intertidal salt marsh. Salt hay intergrades with black rush on the 

 lower marsh edge, while black rush, which appears on a pure thin grassland, 

 grades into the transitional and terrestrial communities on the upland side. 

 Species that may intergrade with black rush include: salt marsh aster, orach, 

 spike grass, sea lavender, common reed ( Phrogmites communis ) , seaside 

 goldenrod ( Solidago sempevirens ) , dwarfed spikerush ( Eleocharis parvula ) , 

 alkali bulrush ( Scirpus paludosus ) , common three-square ( Scirpus americanus ) , 

 salt marsh bulrush ( Scirpus robustus) , prairie cordgrass ( Spartina pectinata ) , 

 saltmarsh sedge (Carex paleacea ) , saltwort, and cattail ( Typha augustifolia ) . 



No research has been done on the transitional marsh but most of the species 

 found in the black rush zone are probably in the transitional marsh as well. 



An interesting phenomenon of New England salt marshes is the existence of 

 numerous salt pannes (irregularly flooded flats) and pond holes (depressions 

 with unconsolidated sediments). A salt panne usually refers to a slight 

 depression in the intertidal marsh surface, generally circular or oval, in 

 which no vegetation grows. These depressions trap standing salt water, which 

 kills most forms of vegetation because evaporation increases the salinity 

 beyond the limits tolerable to most plant species. Pannes in high marsh areas 

 may be referred to as pond holes. 



Pond holes may be of variable depth. They may be derived from relics of 

 intertidal pannes or they may be the result of blocked creeks or decay of the 



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