SALT

MARSH

VEGETATION

Florida Master Naturalist ProgramCOSTAL SYSTEMS OF FLORIDA

PROJECT BY

Noreen Corle Engstrom

Salt marshes occur:• along the coast in the intertidal zone (between low and high

tide) • in low wave energy areas (on the leeward shoreline of barrier

islands or behind protective beaches).

Topography:• Basically consists of a gently inclined plane.

• The elevation gradient from the lowest zone of the marsh (Spartina alterniflora) through the transitionalshrub zone at the upland edge may be less than 1 meter.

• Tidal creeks may modify this basic plan bycreating levees and low berms.

Florida Salt Marshes:• Gulf Coast salt marshes form a nearly continuous band of

vegetation for 140 miles (225 km) from the Ochlockonee River inWakulla County to Tarpon Springs in Pinellas County.

• South of Tarpon Springs salt marshes are less frequent; theirpotential habitats are more commonly mangrove swamps.

• Atlantic Coast salt marshes experience greater tide amplitude than Gulf Coast salt marshes.

Salt marsh vegetation composition is determined by: • hydrology and• salinity

Few vascular plants can tolerate salinity.

• The result is a tendency for salt marsh vegetation to occur in monospecific zones at lower elevations rather than in intermixed plant communities.

• Plant diversity increases with increased elevation above high tide.

Vegetation Zones:1. Spartina alterniflora (smooth cordgrass) 2. Juncus roemerianus (black needlerush) 3. Salt flats4. High marsh5. Transitional Shrub 6. Upland Forest

Spartina and Juncus zones are commonly monotypic.

Helianthus debilis

Gaillardia pulchellus

Baccharis angustifolia

Myrica cerifera

Juniperus virginiana var. silicicola

Spartina bakeri

Distichlis spicata

Paspalum vaginatum

Sporobolus virginicusBatis maritima

Sesuvium portulacastrum

Spartina alterniflora

Spartina patens

Salicornia/Sarcocornia spp.

Typical planting cross section plan by elevation(refer to plant categories on subsequent slides)

MHW= +0.55ft NAVD88MSL= -0.64ft NAVD88

MLW= -1.88ft NAVD88

Borrichia frutescens

Existing site elevation= +4.5ft NAVD88

Max. N/S trailelevation= +3.5ft NAVD88

Muhlenbergia capillarisHamelia patens

Asclepias spp.

Conocarpus erectus

Forestiera segregata

Coccoloba uvifera

Trypsacum dactyloides

(Category A)(Category B)

(Category C)

(Category D)

(Category E)

New marsh surface= +0.3ft NAVD88

Marine Discovery Center Planting Guide for Salt Marsh RestorationUsed with permission.

Vegetation of the Spartina alterniflora Zone

• Plants in this zone are typically flooded twice dailyor nearly so by high tide.

• Soils in this zone tend to be medium or finetextured containing organic matter.

Spartina alternifloraSmooth Cordgrass

Vegetation of the Juncus roemerianus Zone

• Plants in this zone are flooded irregularly by tides.

• Soils of Juncus marshes frequently consist of loam orloamy sand.

Juncus roemerianusBlack Needlerush

Spartina and Juncus Vegetation ZonesJuncus roemerianus (foreground and middle ground)Spartina alterniflora (light green band between the Juncus zones)at a slightly lower elevation.

Vegetation of the Salt Flats

• Elevated areas within the Spartina and Juncus zones which are subject to evaporation and thus higher salinitylevels.

• Plants in this zone are inundated infrequently , usuallyless than once a month.

• Soil is sandy and typically supports sparse growths oflow growing succulents and grasses.

Batis maritimaSaltwort

Borrichia frutescensBushy Seaside Oxeye

Distichlis spicataSaltgrass

Salicornia bigeloviiAnnual Glasswort

Sarcocornia ambiguaPerennial Glasswort

Sesuvium portulacastrumShoreline Seapurslane

Other common plants in the salt flat zone:•Aster tenuifolius (perennial saltmarsh aster)• Limonium carolinianum (sea lavender)• Monanthochloe littoralis (keygrass)

Vegetation of the High Marsh Zone

• Generally less frequently inundated by tidesthan salt flats and barrens.

• Freshwater surface runoff from the adjacentuplands increases soil moisture and reduces soil salinity.

• Vegetation in the high marsh zone includesspecies found growing on salt flats.

Andropogon glomeratusBushy Bluestem

Eustachys petraeaPinewoods Finger Grass

Muhlenbergia capillarisHairawn Muhly Grass

Panicum virgatumSwitchgrass

Pluchea odorataSweetscent

Sabatia stellarisRose of Plymouth

Solidago sempervirensSeaside Goldenrod

Spartina bakeriSand Cordgrass

Sporobolus virginicusSeashore Dropseed

Other common plants in the high marsh zone:

• Agalinis maritima (Saltmarsh False Foxglove)• Eleocharis cellulose (Gulf Coast Sprikerush)• Elionuris tripsacoides (Pan-american balsamscale)• Fimbristylis cymosa (Hurricane Grass)• Fimbristylis spadicea (Marsh Fimbry)• Paspalum vaginatum (Seashore Paspalum)• Scirpus schoenoplectus (Saltmarsh Bulrush)• Spartina patens (Marshhay Cordgrass)• Spartina spartinae (Gulf Cordgrass)

Vegetation of the Transitional Shrub Zone

• Low growing woody plants at the edge of the uplandforest.

• Must be able to withstand hurricane force winds andaerosolized salt.

Baccharia glomerulifloraSilverling

Baccharis halimifoliaGroundsel or Sea Myrtle

Coccoloba uviferaSea Grape

Conocarpus erectusButtonwood

Hamelia patensFirebush

Gaillardia pulchellusFirewheel

Helianthus debilisDune Sunflower

Ilex vomitoriaYaupon Holly

Lycium carolinianumChristmasberry

Forestiera segregataFlorida Privet

Myrica ceriferaSouthern Bayberry

Other common plants of the shrub zone:• Baccharis augustifolia (Saltwater False Willow)

Vegetation of the Upland Forest Zone• can tolerate aerosolized salt and• withstand hurricane force winds

Upland Forest adjacent to a salt marsh is commonly:

• pine-palmetto flatwoods,• cabbage palm thicket or• hydric hammock dominated by live oak.

Juniperus virginianaEastern Red Cedar

Pinus elliottiiSlash Pine

Palmetto repensSaw Palmetto

Sable palmettoCabbage Palm

Quercus virginianaLive Oak

Acknowledgements

Coultas, Charles and Yuch-Ping Hsieh, eds. 1997. Ecology and Management of Tidal Marshes, St. Lucie Press, Delray Beach, FL.

Seabrook, Charles. 2012. The World of the Salt Marsh, University of Georgia Press, Athens, GA.

Taylor, Walter Kingsley. 2013. Florida Wildflowers, University Press of Florida, Gainsville, FL.

Witherington, Blair and Dawn Witherington. 2007. Florida’s Living Beaches, Pineapple Press, Inc., Sarasota, FL.

Wunderlin, Richard P. and Bruce F. Hansen. 2011. Guide to Vascular Plants of Florida, University Press of Florida, Gainsville, FL.

All photographs taken in the field by Noreen Corle Engstrom