KUCHLER TYPE DESCRIPTION
Kuchler Type: Northern cordgrass prairie


PHYSIOGRAPHY : 
The surface of the northern cordgrass prairie is uniform and gently
sloping. It is usually elevated toward the inner and older portions of
the marsh.  Marsh creeks form as natural breaks in alluvial deposits, or
as inward dissection of marine sediments.  Natural levees can develop
along marsh creeks [15,32,36].


CLIMATE : 
Northern cordgrass prairie occurs in a range of climates from hot
continental to subtropical [29,60].


SOILS : 
Tidal saltmarsh soils are hydric, very poorly drained silts, mucks, and
peats.  Peaty soils are more common along the northern Atlantic coast
than further south [45,48].  There are several types of peat formations,
each with distinctive characteristics.  Generally, surface materials
consist of coarse, fibrous, yellowish-brown peat which has gradually
accumulated over black clays, mud flats, or loose sand [45].  Sands tend
to be deposited near the mouths of embayments; clays and silts are
deposited toward the head of tidal creeks and meanders [36].  Soil
salinity is variable depending on tidal inundation rate, rainfall, tidal
creeks and drainage slope, soil texture, vegetation, depth to water
table, and fresh water inflow [8].


VEGETATION : 
Classification:  The northern cordgrass prairie, as described by Kuchler
[29], appears to correspond to the grass-dominated vegetation zones of
tidal saltmarshes from Maine to northeastern Florida.  The term northern
cordgrass prairie is not used in the literature; where this author is
confident that the community under discussion in the literature
corresponds exactly to that described by Kuchler, the term northern
cordgrass prairie will be employed; more general statements about
saltmarshes or specific statements about particular types of communities
not explicitly corresponding to northern cordgrass prairie will be
reported as described or used in the literature.  Some of the
generalizations that can be made about northern cordgrass prairie apply
to or are based on southern cordgrass prairie, which is composed of
similar vegetation and develops under related (but not identical)
ecological conditions.

Chapman [8] recognized three subgroups of coastal marshes for the
eastern United States:  the Bay of Fundy subgroup, the New England
subgroup, and the Coastal Plain subgroup, which includes marshes on the
Gulf coast.  Northern cordgrass prairie probably corresponds to the New
England and Coastal Plain subgroups.  Shaw and Fredine [45] described 20
wetland types, two of which (16:  coastal salt meadows, and 18:
regularly flooded saltmarshes) appear to closely correspond to northern
cordgrass prairie, and two of which (15:  coastal saltflats and 17:
irregularly flooded saltmarshes) contain some of the elements of the
northern cordgrass prairie.  De la Cruz [15] described the differences
between Atlantic and Gulf coast marshes.  These differences are largely
due to the differences in hydrology and dominant sedimentation
processes.  Gulf coast saltmarshes are extremely flat, dependent on
alluvial sediments, less saline, and have less well defined vegetation
zones than Atlantic coast saltmarshes.  Atlantic coast marshes are more
dependent on tidal action, develop more distinct vegetation zones, and
develop peatier soils than do Gulf coast saltmarshes [15].

The wetland classification scheme proposed by Cowardin and others [11]
has been in widespread use since its publication.  Northern cordgrass
prairie corresponds most closely to estuarine persistent emergent
wetland which occurs in three tidal zones:  irregularly exposed,
regularly flooded, and irregularly flooded.  The irregularly flooded
zone is dominated by saltmeadow cordgrass (Spartina patens), and/or
dwarf smooth cordgrass (S. alterniflora), and/or saltgrass (Distichlis
spicata), the three dominants listed by Kuchler for northern cordgrass
prairie [11].  In the literature, this zone is most often referred to as
high salt marsh (which describes its position relative to the tides).
The regularly flooded zone is dominated by tall smooth cordgrass, and is
generally referred to as low saltmarsh.

The high saltmarsh occurs in a complex mosaic with several other
communities such as salt shrub, low saltmarsh, and salt panne [43].
Salt shrub communities occur at the upland side of high saltmarsh; salt
pannes are depressions that occur within the high saltmarsh that are
extremely saline, and either unvegetated or sparsely vegetated.
Northern cordgrass prairie appears to encompass both high and low
saltmarsh, and vegetative elements of northern cordgrass prairie also
occur in other communities.

Vegetation:  Tidal saltmarshes are dominated by only a few genera, and
many species occur in monotypic stands or patches [1].  High saltmarsh
consists of a mosaic of patches of single graminoid species [32,43].
The most common species in the high saltmarsh are saltmeadow cordgrass
and dwarf smooth cordgrass.  The dwarf form grows 6 to 32 inches [17-80
cm] tall, and the tall form (which is found only in the low saltmarsh)
ranges up to 10 feet (3 m) in height [32].  There is an ongoing debate
as to whether the differences in height growth between tall and dwarf
smooth cordgrass are due to genetic or to environmental causes [32].
Also common are large areas of saltgrass and saltmeadow rush (Juncus
gerardi).  Characteristic species of the upper slope of the high marsh,
where it grades into less saline environments are saltmeadow rush,
switchgrass (Panicum virgatum), common reed (Phragmites australis),
sea-lavender (Limonium carolinianum), and slender salt marsh aster
(Aster tenuifolius) [32,36,43].  Marine algas form dense mats on surface
sediments.  Other plants, which occur in low numbers, can include
glassworts (Salicornia spp.), saltmarsh sand-spurry (Spergularia
marina), and lesser sea-blite (Suaeda maritima) [43].  On infrequently
inundated flats or pannes, strict halophytes such as perennial glasswort
(Salicornia virginica), sea-blite (Suaeda linearis), and saltgrass are
dominant [10].  Black rush (J. roemeriana) occurs from New Jersey south
to the Gulf coastal marshes, increasing in abundance with decreasing
latitude.  Saltmeadow rush decreases in abundance with decreasing
latitude, apparently replaced by black rush [8].

New England and Coastal Plain saltmarshes are dominated by tall smooth
cordgrass in the lower marsh.  In New England, saltmeadow cordgrass,
saltgrass, saltmeadow rush, and dwarf smooth cordgrass dominate the
upper marsh.  There is a distinct boundary between low marsh and high
marsh at the elevation of mean high tide.  The upper boundary of the
high marsh is determined by the elevation of exceptional high tide.  On
the Coastal Plain, saltmeadow cordgrass, saltgrass, glassworts, and
black rush dominate the upper marsh [32,36,49].


WILDLIFE : 
Atlantic coast saltmarshes are used for nesting by American black duck
(Anas rubripes), blue-winged teal (A. discors), laughing gull (Larus
atricilla), Forster's tern (Sterna forsteri), willet (Catoptrophorus
semipalmatus), northern harrier (Circus cyaneus), marsh wren
(Cistothorus palustris), eastern meadowlark (Sturnella magna),
sharp-tailed sparrow (Ammodramus caudacutus), and seaside sparrow (A.
maritimus).  Other birds found in saltmarshes include ring-necked
pheasant (Phasianus colchicus), common snipe (Gallinago gallinago),
clapper rail (Rallus longirostris), and other rails (Rallus spp.).
Saltmarshes are important stopover areas for migrating snow goose (Chen
caerulescens), peregrine falcon (Falco peregrinus), shorebirds, and
wading birds [32,43,47,48].  Wading birds including herons and egrets
(Ardeidae) and glossy ibis (Plegadis falcinellus) feed and nest in and
adjacent to tidal saltmarshes [49].  New Jersey saltmarshes are prime
wintering grounds for American black duck, snow goose, greater and
lesser scaup (Aythya marila and A. affinis), brant (Branta bernicla),
Canada goose (B. canadensis), and mallard (Anas platyrhychos).  Northern
pintail (A. acuta) and canvasback (Aythya valisineria) overwinter in the
Hackensack Meadowlands [48,49].  

Furbearing mammals inhabiting saltmarshes include muskrat (Ondatra
zibethicus) and nutria (Myocastor coypus), both of which are more
abundant in slightly brackish marshes than in more saline areas, and
masked shrew (Sorex cinereus) [36,46,48].  Mammals feeding in
saltmarshes but denning elsewhere include beaver (Castor canadensis),
red fox (Vulpes vulpes), gray fox (Urocyon cinereoargenteus), mink
(Mustela vison), northern river otter (Lutra canadensis), raccoon
(Procyon lotor), long-tailed weasel (M. frenata), and skunks (Spilogale
and Mephitis spp.).  White-tailed deer (Odocoileus virginianus) and mule
deer (O. hemionus) feed in saltmarshes [45].  Rodents inhabiting high
saltmarsh in New England include meadow vole (Microtus pennsylvanicus),
meadow jumping mouse (Zapus hudsonius), white-footed mouse (Peromyscus
leucopus), and house mouse (Mus musculus) [36].  

Reptiles inhabiting saltmarshes include diamond-backed terrapin
(Malaclemys terrapin) [48] and American alligator (Alligator
mississippiensis) [45].  

Invertebrates include fiddler crabs, northern horse mussel, other
mussels, coffee-bean snail, oysters, and clams [2,43].  Insects include
saltmarsh mosquitoes and greenhead flies [43].


ECOLOGICAL RELATIONSHIPS : 
Ecosystem Development and Succession:  Tidal marsh formations are
essentially dynamic; there is a progression from bare sand or mud flat
through a range of plant communities to the upper edge of the marsh
where dryland communities develop [9].  Tidal marshes typically develop
behind barrier islands or beaches or along tidal rivers [48].  Where
water is slowed and sediments drop out, sand- and mudflats are created.
Plants (usually smooth cordgrass) colonize these flats; the presence of
the plants further slows the water, and the plants trap and hold
sediments, creating a slow rise in elevation [2,33,48].  This slow rise
in elevation leads to succession to more upland community compositions
[32].  Marshes grow both in a seaward direction due to sedimentation,
and landward when rising sea level increases salinity and inundation in
upland areas [36].

The long-term stability of a saltmarsh is determined by the relative
rates of sedimentation and coastal submersion [32].  In many areas salt
marshes are gradually advancing into low-lying uplands or into nontidal
wetlands; this has been largely attributed to the global rise in sea
level.  Rising sea level can result in a loss of saltmarsh acreage
where marshes become permanently flooded [48].  In the northeastern
United States, marsh accretion rates are high enough to balance current
rates of sea level rise, and marshes are in a relatively stable
condition [36].

On the southern coasts (particularly in the Carolinas and Georgia), the
local variety of saltmeadow cordgrass (Spartina patens var. monogyna)
grows up through a layer of sand deposited by storm waves, quickly
stabilizing overwash deposits and preventing sand from being piled into
dunes.  This creates barrier profiles that are low and flat.  The
northern variety of saltmeadow cordgrass (S. p. var. patens), which
occurs north from New Jersey, is killed by sand deposition which allows
sand surfaces to be piled into dunes.  The result is a higher, more
irregular profile in the northern barriers [25].

Hydrology:  Ocean tides are the dominant hydrologic feature of northern
cordgrass prairie.  On the Atlantic coast, tides are semidiurnal, with
two high tides and two low tides per day [15,48].  Estuarine wetlands
are influenced by both tides and inland hydrology.  These occur where a
river meets the ocean and encompass a range of salinities, from fresh to
brackish to saline [8,32,48].

Structure:  Vegetation distribution is determined by the complex
interaction of many factors that include tides, elevation (a matter of
inches), salinity, freshwater influx, sedimentation rates, current
velocity and direction, and soil fertility [25,32,36].  The most seaward
terrestrial plant population is usually tall smooth cordgrass [25].  In
Connecticut, tall smooth cordgrass is a fairly accurate indicator of the
landward extent of mean high tide.  Diversity of plant species increases
in a landward direction [48].  Dwarf smooth cordgrass forms extensive
stands just above the low marsh.  Within these stands are salt pannes:
shallow depressions of high salinity that are sparsely vegetated or
occasionally colonized by dwarf smooth cordgrass, glassworts, and marsh
fleabane (Pluchea odorata) [43,48].  Above the dwarf smooth cordgrass
zone, common reed, saltmeadow cordgrass, and saltgrass predominate.
Common reed forms pure or mixed stands, saltmeadow cordgrass forms
nearly pure stands, and saltgrass is commonly intermixed with other
species.  At slightly higher elevations, saltmeadow rush bands form,
often mixed with marsh-elder (Iva frutescens).  At the upland edge of
the northern cordgrass prairie occur switchgrass, common reed, sea
myrtle (Baccharis halimifolia), marsh-elder, wax myrtle (Myrica
cerifera), and eastern red-cedar (Juniperus virginiana) [48].

In brackish marshes smooth cordgrass, saltmeadow cordgrass,
narrow-leaved cattail (Typha angustifolia), big cordgrass (Spartina
cynosuroides), common reed, and rose mallow are major dominance types.
Smooth cordgrass and saltmeadow cordgrass are often intermixed with
patches of big cordgrass and common reed.  Big cordgrass becomes more
important with decreasing salinity, and where marsh waters are nearly
fresh marshes are dominated by big cordgrass and freshwater species
[48].  Literature on the vegetation structure of tidal salt marshes has
been reviewed by Adams [1], Mitsch and Gosselink [32], Niering and
Warren [35], Nixon [26], and Redfield [40].

Productivity:  Tidal salt marshes are highly productive ecosystems.  A
large portion of this productivity is attributed to halophytic grasses;
however, most of the annual primary productivity of a saltmarsh is
attributed to phytoplankton and algae [42].  Net primary productivity
has been estimated/calculated for a number of marsh species at a number
of locations; some of the abovementioned reviews include tables of
productivity by species.  A bibliography of coastal marsh productivity
is available [53].  Saltmarsh productivity is exported to other systems
(primarily marine and estuarine) in the form of detritus.  Numerous
detritus consumers form the bases of food webs that depend on tidal
saltmarsh productivity [2].

Plant-Animal Interactions:  Consumers living in tidal saltmarshes are
either grazers or alga-detritus feeders.  Few comprehensive studies of
the animals, particularly invertebrates, have been conducted in
saltmarshes [32].  Some interesting relationships have been reported,
however.  Through their burrowing activities, fiddler crabs increase
soil drainage, decomposition of belowground debris, and the oxygen
content of the soil, all of which benefit smooth cordgrass.  Ribbed
mussels attach to smooth cordgrass in the low salt marsh and buffer it
from physical disturbance.  They also deposit nitrogen-rich feces at the
growing bases of smooth cordgrass plants [6].

Related categories for Kuchler Type: Northern cordgrass prairie