Freshwater Tidal Marsh State Rank: S1 - Critically Imperiled

Cross section showing characteristic species of bulrush, arrowhead, pickerel-weed, Freshwater Tidal Marsh. and water dock frequently occur. Freshwater cord-grass, threesquare, and water hemp are typical of rockier substrates. More sparsely vegetated mud flats include spike sedges, water purslane, water starwort and bittercress. Differentiating from Related Communities: The Illustrator: Brian Reid. key difference from other types of Freshwater Marsh is that Freshwater Tidal Marshes provide habitat for nesting Tidal Marshes are restricted to the area of Description: Freshwater Tidal on large rivers. Rocky shores have songbirds. Freshwater mussels are locally freshwater tidal action on coastal rivers Marshes occur on free-flowing coastal sparse, low growing annuals in patches of abundant. rivers just upstream of the salt front shallow soils. Mud flats in the river and streams above the zone of regular salt carried by incoming high tides. They are channel regularly have sediment water incursion. A difference from Examples with Public Access: flooded twice daily by the freshwater that deposition and prolonged inundation. Brackish Tidal Marshes is the lack salt West Newbury Conservation Area, West is backed up as it meets resistance from They are sparsely vegetated with a suite tolerant plants. Long’s bittercress, estuary Newbury; Willow Brook Farm Preserve the high tides downstream. Being along of low-growing plants. arrowhead, and estuary beggar-ticks, (Wildlands Trust), Pembroke; Stetson the shores of dynamic rivers, freshwater although shared with Brackish Tidal Meadows, Norwell; Mounces Meadow, tidal marshes are often structurally Characteristic Species: Freshwater Marshes, most commonly occur in the Marshfield. diverse. Freshwater tidal marsh represents Tidal Marshes are characterized by salt freshwater situation. Some other species the upstream end of a tidal gradient from intolerant plant species, typically a rich that co-occur in Freshwater and Brackish salt marsh, to brackish tidal marsh, to association of emergent grasses, sedges, Tidal Marshes are more likely to be found freshwater tidal marsh. Tidal amplitude rushes and forbs, with only occasional in the brackish condition: Lilaeopsis or may be up to 150 cm. Average annual shrubs in upper edges of the backmarsh. eastern grasswort, Atlantic mudwort, salinity is less than 0.5 ppt (from 0.5 ppt Narrow-leaved cattail and sweet flag water-pimpernel, Parker’s pipewort, and to 5 ppt salinity there is a gradient of occasionally forms exclusive stands, and Eaton’s beggar-ticks. Many of these are species to brackish conditions which have climbing hempweed often sprawls over uncommon, even in the appropriate an average annual salinity of 5-18 ppt). large patches of backmarsh. Dominant habitats. species include blue joint, lakeside and High marsh begins with an abrupt bank Habitat for Associated Fauna: of peat 1-3 feet above mean low water. It tussock sedges, narrow-leaved cattail, This community provides outstanding is often the most diverse vegetated zone wild rice, smartweeds, tearthumbs, general wildlife habitat, with abundant of the freshwater tidal marsh. Low marsh jewelweed, climbing hempweed, false food sources for migratory and wintering is on muddy or rocky sloping shores pimpernel, and sweet flag. Low marsh waterfowl, and is generally associated below the bank of high marsh particularly often has stand-forming emergent plants with tough mat-forming rhizomes that with river reaches with spawning habitat Freshwater Tidal Marshes are mixed resist erosion; annuals may also dominate for anadromous fisheries. It tends to have herbaceous marshes flooded by daily large sections of marsh. Large stands of more vertebrate species, such as tides, and occurring in the freshwater wild rice usually dominate muddy areas, freshwater snakes and muskrats, than do reach of coastal rivers; the Brackish Tidal Marshes. Freshwater Wild rice in a Freshwater Tidal Marsh. Photo: however stands of sweet flag, soft-stem Joanne Singfield, NHESP.

From: Classification of Natural Communities of Massachusetts htthttpp://www;mass;gov/nhesp/://www;mass;gov/nhesp/ Updated: 2016 Natural Heritage & Endangered Species Program, Division of FishFisheeriesries & Wildlife, 1 Rabbit Hill Rd;, Westborough, M! 01581 (508) 389-6360