APPENDIX E - VEGETATION
Vegetation has been used for stabilizing shorelines either as a substitute for, or supplement to,
structures. Vegetation is an inexpensive, and generally easy, approach to providing erosion control. It is
not, however, applicable to all situations. It cannot always prevent erosion, nor can it stop the recession
of bluffs caused by groundwater seepage. In order to confront these types of problems, the landowner is
advised to consider a combination solution such as a structural device and vegetation.
Vegetation uses are limited by site characteristics such as climate, soil properties, wave exposure,
and salinity regimes. The following discussion will focus on species which may be used for marsh,
beach, dune and slope plantings. For each species, the applicable geographical region and planting
specifications will be described. Further information on these and other species not mentioned in this
report can be obtained from offices of county soil conservation services, state coastal zone management
programs, or Corps of Engineers districts.
MARSH PLANTS
Coastal marshes are those herbaceous plant communities, which are normally inundated or
saturated by surface or groundwater. They may be narrow fringes along steep shorelines or they may
cover wide areas in shallow, gently sloping shore regions typically found in bays and estuaries (Figure E-
1). In saltwater marshes, salinity is generally equal to or slightly less than seawater (35 parts per
thousand salt). Freshwater marshes experience water level fluctuations resulting from groundwater table
and seasonal climatic changes.
To establish a coastal marsh, the site must be evaluated based on geographic area, tidal elevation
and range, salinity, fetch length, and soil properties. The vegetation prevalent in three saltwater marsh
regions and the Great Lakes are discussed below. Planting specifications are summarized in Table E-1.
The suitability of a site for marsh plantings can be evaluated using Figure E-2.
Atlantic Coast Marshes
Common vegetation found in Atlantic coast marshes is described briefly below.
Smooth Cordgrass (Spartina alternaflora).
This is the dominant marsh grass from
Newfoundland to about central Florida. It is well adapted to soils not exposed to air that range from
coarse sands to silty clays. Three distinct height forms are recognized. The tall form is generally found
along tidal creeks and drainage channels, the short form grows on flat or gently sloping areas away from
channels, and the medium form, when present, is found in transition areas between stands of the short
and tall forms.
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