FA272/FA272: Elevation Tolerances of Salt Marsh-Upland Ecotone Species: A Restoration Guide

This guide aims to aid salt marsh-upland ecotone restoration by providing a list of 24 key species and the elevations at which they should be planted in restoration projects. It is intended for restoration practitioners, land and natural resource managers that are interested in coastal restoration, and coastal landowners interested in erosion prevention and residential restoration projects such as living shorelines. Some example uses include living shorelines and facilitating marsh migration into uplands in the face of sea level rise.

Introduction

In this publication, we present a sample of Florida salt marsh-upland ecotone species and their elevation tolerances. The goal of this project was to inform ecotone restoration by determining optimum conditions for planting key Florida salt marsh-upland ecotone species, giving restoration practitioners tools to include ecotone species in salt marsh restoration projects. This guide is intended for restoration practitioners and land managers who are interested in coastal restoration. It may also be useful for coastal landowners to aid in erosion prevention and residential marsh restoration/living shorelines.

Photograph of a salt marsh to upland ecotone in Eastern Florida. It's a thin band of land less than 100 meters wide with forest on the left and a tidal channel on the right, visible only in the top right of the picture. The species change as elevation decreases from the trees over to the water, with first a thin, 1 meter wide, band of taller bunchgrasses. Then there's a 2 meter wide band of shorter brighter green grasses. Next comes a 20 to 30 meter wide band of Spartina alterniflora. This band features grasses less than a foot tall, growing more sparsely with lots of mud visible amongst it. Finally, the last band before the water, visible only in the top right of the photo, is a mudflat visible because the tide is low. A person stands in the Spartina in the background looking at the water. — Figure 1 . An example of a salt marsh-upland ecotone.
Credit: Emory Wellman, UF/IFAS.

Background

Salt marshes in Florida are critical ecosystems that provide flood and hurricane protection, filter water, act as habitat for important and endangered species, capture carbon, and facilitate recreational activities such as fishing (Teal and Howes 2000). Restoring these ecosystems is common practice in Florida, but restoration is complicated, and current restoration methods are not perfect. Salt marsh restoration in Florida often relies on planting one or a small handful of species. This approach could be a problem because salt marshes naturally feature a variety of species, and species diversity aids restoration efforts (Callaway 2005). Additionally, salt marshes feature different species in areas with different degrees of flooding (Figure 2), so it’s rare for one species to thrive in all parts of the marsh (Cui et al. 2011).

One area underrepresented in Florida salt marsh restoration is the salt marsh-upland ecotone. In any type of environment, the ecotone is the zone of transition between one ecosystem type and another. They generally occur over a narrow band and feature unique conditions and species (Attrill and Rundle 2002). The upland ecotone of a salt marsh is the area at the inland border immediately next to the high marsh, where the high marsh grows into the terrestrial zone and flooding is less frequent than in the rest of the marsh due to higher elevations, lessening salinity. On the salt marsh side, the species present are mainly determined by physical forces. The plants that can survive there are ones that can handle the harsh conditions of high salinity and frequent flooding (Callaway 2005; James and Zedler 2000). Upland ecotone species do not move down into the marsh because they are not able to handle these stressful conditions. On the upland side, the species present are mainly determined by competition and facilitation, negative and positive interactions with neighboring plants (Cui et al. 2011; James and Zedler 2000). Upland species are often not as adapted to dealing with the periodic flooding and higher salinity present in the ecotone, but ecotone species lose this competitive advantage in higher elevation upland environments (James and Zedler 2000). Essentially, ecotone species are the ones that can outcompete other plants in areas of infrequent flooding and intermediate salinity.

Salt marsh-upland ecotones are ecologically important. They aid and filter the transfer of materials, organisms, and nutrients between ecosystems; support diverse animal and plant communities; and prevent erosion (Kark 2012). These ecotones are threatened, increasingly so in a changing climate. While restoration of salt marsh ecotones is increasingly common on the west coast of the United States and has been done in northern areas of the Atlantic coast, it appears to be mostly ignored in Florida. The goal of this project was to support ecotone restoration by determining optimum conditions for planting key Florida salt marsh-upland ecotone species.

A drawing of the gradient of elevation and associated vegetation zones from the water to the uplands labeled “Protected low-energy shoreline of a northeastern Gulf Coast salt marsh.” Stylized drawings of plants along the transect include from left to right Spartina alterniflora; tall Juncus roemerianus; short Juncus roemerianus; two patches of Distichlis spicata/Salicornia spp. with a barren patch between them; Spartina patens/Juncus roemerianus; Baccharis halimifolia/var. frutescens; and pine trees representing upland habitat. A vertical rule along the left margin shows the elevation in meters from -0.5 to 0, 1.0, and finally 2.0. — Figure 2. An example of the gradient from salt marsh to upland on the Gulf coast of Florida. At lower elevations (left), there are more salt-tolerant species (*Spartina alterniflora*, *Juncus roemerianus*), and moving inland to higher elevations (right), species composition changes (*Distichlis spicata*, *Baccharis halimifolia*).
Credit: Diagram from UF/IFAS Extension's Florida Wetlands Extension Program at soils.ifas.ufl.edu.

Use

This guide should be used to determine where to plant these ecotone species when practicing salt marsh restoration. Before planting any of the species listed in this guide in the ecotone of a restoration project, it’s important to carefully consider the upland community. The upland system impacts which species grow in the ecotone because much of the ecotone community is a mixture of marsh and upland species. This guide contains a sample of species occurring in a variety of salt marsh-upland ecotones but is not intended to be an exhaustive list. Only species occurring in the ecotone itself were included, and tree species were avoided as they were considered too slow-growing to be viable for initial restoration. This guide is intended for early steps of the restoration process, and it therefore targets pioneer species. Other species may be planted or may naturally relocate to the ecotone after the land is stabilized by the species included in this guide. The community types listed for each species in the guide can be used to inform which would be best suited for your restoration project.

The guide provides a description of each species along with a summary of the elevations at which the plant is found throughout Florida. The graphs and tables show the range of elevations that each species can tolerate and the elevation at which they are most commonly found. We suggest contacting local nurseries to find out what plants they have available and the capacity of each nursery to propagate in quantities necessary for your restoration project. The specific conditions at your restoration project will be unique. The elevation recommendations in the guide are a starting point, but experimentation and pilot plantings may be necessary to determine the exact elevations for each plant that ensure the highest rate of success.

Methods

This project developed a list of important salt marsh-upland species from the combination of several sources. These include a short list of ecotone species in a Mississippi salt marsh created by another ecotone researcher (Anderson et al. 2022), a source detailing species in different parts of a salt marsh published by the Virginia Institute of Marine Sciences (Living Shorelines n.d.), information synthesized from the Florida Natural Areas Inventory (FNAI) (FNA Inventory 1990), lists of high marsh plants published by FloridaLivingShorelines.com, and recommendations by UF/IFAS experts on key species that were missing from the FNAI list. Plants were chosen if they were found in the ecotone in Florida. It is important to note that these species do not necessarily grow exclusively in the ecotone and may be found in other systems. We defined ecotone species as plants that were neither obligate wetland nor obligate upland species, had some level of salt tolerance, and were either listed as salt marsh-upland ecotone species by one of the previously listed sources or were listed by the FNAI as growing both in salt marshes and in upland habitats. We chose a subset of species as a sample of salt marsh-upland ecotone plants in Florida. For questions about methods and selection criteria of species contact alsiegel@vims.edu.

We obtained species location data from iNaturalist (Figure 3), a smartphone application that allows users to identify and document plants they find (iNaturalist.org). Elevations for each plant’s location were then determined using elevation data from the National Elevation Dataset published by the United States Geological Survey, which uses meters and the North American Vertical Datum of 1988 (NAVD88) as the vertical datum (Gesch et al. 2018). A vertical datum is a reference to determine relative elevation, similar to saying feet above sea level. Meters NAVD88 describes how many meters above or below a theoretical reference determined by the National Geodetic Survey. We used these data to characterize the elevation tolerances of each species within the entire state of Florida. We used the Florida Cooperative Land Cover Map (FNA Inventory 2010) to filter the data to include only species growing in salt marshes or in systems that directly border salt marshes. This allowed us to obtain a better estimate of only individuals growing in the salt marsh-upland ecotone.

Data processing was done in ArcGIS Pro, RStudio, and Microsoft Excel. Pictures came from the Atlas for Florida Plants and iNaturalist observations under the public domain (CC0).

Our analysis delivered a list of 24 ecotone species and information on their elevation tolerances that can be used to inform future research and allow the inclusion of ecotone species in future salt marsh restoration projects.

Two Florida maps side by side. The left map showing Fimbristylis cymosa reveals that most sightings were in the southern coastal portion of the state with very few in the Panhandle and none as far north as Tallahassee or Jacksonville. There is a single purple dot off the tip of the state indicating a sighting at the Dry Tortugas national park. The right map shows Baccharis halimifolia sightings, with more sightings and a higher concentration of inland sightings. Sightings extend all the way up to the northern border of the state and are thickly clustered along both coasts into the Panhandle and around both Jacksonville and Tallahassee. — Figure 3. Maps of locations at which two sample species were reported on iNaturalist. The beige and gray represent salt marshes and bordering systems. Green points represent plants found in salt marshes and bordering systems, and purple points show all other locations where the plant was found. *Fimbristylis cymosa* (left) is an example of a species found mainly near the coast, while *Baccharis halimifolia* (right) represents a species that is found in a variety of areas, including inland.
Credit: Ari Siegel, UF/IFAS.

Plant List

Acrostichum aureum
Andropogon glomeratus
Baccharis angustifolia
Baccharis halimifolia
Batis maritima
Borrichia frutescens
Cynanchum angustifolium
Distichlis spicata
Fimbristylis cymosa
Flaveria linearis
Ipomoea sagittata
Iva frutescens
Limonium carolinianum
Lycium carolinianum
Morella cerifera
Muhlenbergia capillaris
Pluchea odorata
Sesuvium portulacastrum
Solidago sempervirens
Sporobolus bakeri (Spartina bakeri)
Sporobolus pumilus (Spartina patens)
Sporobolus virginicus
Symphyotrichum tenuifolium
Yucca aloifolia

All Plant Data Summarized

This data represents the general location of the salt marsh-upland ecotone in Florida, although the exact elevation range of this ecotone may vary regionally. It was created by combining the final filtered data from all 24 species and provides a summary of the elevations at which Florida ecotone plants can be found.Elevation in Meters, Summary of Data for All 24 Species

Minimum: −1.500 1st Quartile: 0.440 Median: 0.770 Mean: 0.834 3rd Quartile: 1.070 Maximum: 11.360

A boxplot showing the distribution of ecotone species by elevation. There is a strong spike around 1m in elevation.

A spray of yellow-green fronds growing in brown sandy mud and pooled water. The water reflects the sky with white clouds. — Credit: iNaturalist, CC0: https://creativecommons.org/publicdomain/zero/1.0/.

Achrostichum aureum

Acrostichum aureum (golden leather fern) is a fern species found in salt marshes and mangrove swamps. This is a large plant with fronds growing up to six feet tall. It is widespread and not threatened.

Where to Plant Acrostichum aureum

Acrostichum aureum should be planted in the salt marsh ecotone between −0.19 and 0.15 meters NAVD88 for best results. It can survive at higher elevations but should not be planted any lower than this range.

Below we provide more detail on where Acrostichum aureum plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −1.500
First Quartile: −0.190
Median: 0.000
Mean: −0.108
Third Quartile: 0.150
Maximum: 1.370

Bar graph of Acrostichum aureum counts from plants found in and bordering salt marshes at different elevations. There is a large peak at 0 meters.

Acrostichum aureum growing on a rocky shoreline. The Acrostichum fronds are bright green with brown patches of dead fronds. The water is turquoise, and the rocks slope steeply down until a drop off into the water. Other species, predominantly grasses, feature on the slope. — . Credit: iNaturalist, CC0.
Credit: iNaturalist, CC0

Andropogon glomeratus

Andropogon glomeratus (bushy bluestem) is a grass species found in salt marshes, glades marshes, and coastal grassland habitats. This grass grows up to six feet high and has blue-green leaves in summer. It is widespread throughout the Americas and is a potential invasive species outside of its native range.

Where to plant Andropogon glomeratus

Andropogon glomeratus should be planted in the salt marsh ecotone between 0.880 and 1.650 meters NAVD88 for best results. It can survive at significantly higher or significantly lower elevations.

Below we provide more detail on where Andropogon glomeratus plants have been found in and near salt marshes.

Elevation in Meters

Minimum: 0.220 First Quartile: 0.880Median: 1.140Mean: 1.425Third Quartile: 1.650Maximum: 5.460

Bar graph of Andropogon glomeratus counts from plants found in and bordering salt marshes at different elevations. There is a peak centered around 1 meter, and the graph is skewed right.

A stalk of pale green Andropogon glomeratus seedheads in front of a field of tall brown grasses. — Credit: iNaturalist, CC0..

Baccharis angustifolia

Baccharis angustifolia (saltwater falsewillow) is a shrub species found in salt marshes and sand dunes. It can grow up to thirteen feet and has narrow leaves. It is native to the United States Southeast.

Where to plant Baccharis angustifolia

Baccharis angustifolia should be planted in the salt marsh ecotone between 0.465 and 0.965 meters NAVD88 for best results. It can survive at slightly higher and lower elevations.

Below we provide more detail on where Baccharis angustifolia plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.1501st Quartile: 0.465Median: 0.760Mean: 0.7203rd Quartile: 0.965Maximum: 1.790

Bar graph of Baccharis angustifolia counts from plants found in and bordering salt marshes at different elevations. There is a peak starting at .1 meters that hits a maximum around .9 meters.

A Baccharis angustifolia shrub in front of blue siding. Pale green leaves and narrow white flowers grow out of dark green twigs and smaller branches, which grow from brown main stems. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Baccharis halimifolia

Baccharis halimifolia (groundsel tree/sea myrtle) is a shrub/tree species found in salt marshes and other wetlands. It grows up to twelve feet high and has white flowers. It is native to parts of the Americas.

Where to plant Baccharis halimifolia

Baccharis halimifolia should be planted in the salt marsh ecotone between 0.620 and 1.335 meters NAVD88 for best results. It can survive at higher elevations but should not be planted much lower than this range.

Below we provide more detail on where Baccharis halimifolia plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.8701st Quartile: 0.620Median: 0.930Mean: 1.0453rd Quartile: 1.335Maximum: 11.360

Bar graph of Baccharis halimifolia counts from plants found in and bordering salt marshes at different elevations. There is a peak starting around 1 meter.

A branch of pale green Baccharis halimifolia juts out amid a dark brown forest floor. The branch features pale green leaves and long narrow white flowers.

with white flowers. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Batis maritima

Batis maritima (saltwort) is a succulent scrub species found in salt marshes and mangrove swamps. It grows in dense colonies and can reach from between a few inches high to five feet tall. It is edible and native to the East and West Coasts of the Americas.

Where to plant Batis maritima

Batis maritima should be planted in the salt marsh ecotone between 0.250 and 0.675 meters NAVD88 for best results. It can survive at slightly higher and lower elevations, but the majority lives in this range.

Below we provide more detail on where Batis maritima plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.9401st Quartile: 0.250Median: 0.440Mean: 0.4623rd Quartile: 0.675Maximum: 2.330

Bar graph of Batis maritima counts from plants found in and bordering salt marshes at different elevations. There is a peak at around .5 meters.

A patch of Batis maritima shows long branches with many leaves branching off. — Credit: iNaturalist, CC0.

Borrichia frutescens

Borrichia frutescens (bushy seaside oxeye) is an herb/shrub species found in salt marshes, mangrove swamps, and coastal berms. It grows up to three feet high and can attract butterflies. It is native to the United States and Mexico.

Where to plant Borrichia frutescens

Borrichia frutescens should be planted in the salt marsh ecotone between 0.318 and 0.863 meters NAVD88 for best results. Some plants survive at higher and slightly lower elevations, but most live in this narrow range.

Below we provide more detail on where Borrichia frutescens plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −1.2501st Quartile: 0.318Median: 0.590Mean: 0.6143rd Quartile: 0.863Maximum: 6.100

Bar graph of Borrichia frutescens counts from plants found in and bordering salt marshes at different elevations. There is a peak at around .5 meters.

A Borrichia frutescens shrub growing among short grasses. The pale rounded green leaves grow densely on the shrub. — Credit: iNaturalist, CC0.

Cynanchum angustifolium

Cynanchum angustifolium, or Pattalias palustre (gulf coast swallowwort/vine milkweed) is a vine species found in salt marsh, coastal hammock, and sand dune habitats. It can grow up to ten feet long and supports monarch butterflies. It is native to the United States Atlantic and Gulf coasts.

Where to plant Cynanchum angustifolium

Cynanchum angustifolium should be planted in the salt marsh ecotone between 0.610 and 1.030 meters NAVD88 for best results. It should not be planted much outside of this range.

Below we provide more detail on where Cynanchum angustifolium plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.4501st Quartile: 0.610Median: 0.800Mean: 0.7913rd Quartile: 1.030Maximum: 1.550

Bar graph of Cynanchum angustifolium counts from plants found in and bordering salt marshes at different elevations. The maximum occurs around .75 meters.

A close-up view of Cynanchum angustifolium stems growing out of the sand. The thin branches of the vine grow among a patch of narrow grasses. — Credit: iNaturalist, CC0.

Distichlis spicata

Distichlis spicata (saltgrass) is a grass species found in salt marshes, mangrove swamps, coastal berms, and glades marshes. It is generally short but can reach up to one and a half feet high and often grows in dense clumps. It is native to the Americas.

Where to plant Distichlis spicata

Distichlis spicata should be planted in the salt marsh ecotone between 0.450 and 1.043 meters NAVD88 for best results. Some specimens can survive above this range, but it should not be planted any lower.

Below we provide more detail on where Distichlis spicata plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −1.5001st Quartile: 0.450Median: 0.680Mean: 0.7083rd Quartile: 1.043Maximum: 2.580

Bar graph of Distichlis spicata counts from plants found in and bordering salt marshes at different elevations. There are few datapoints, with a loose peak at around .5 meters.

Pale green Distichlis spicata grows in a dense mat around a blump of mud by on a beach. In the background a fallen tree reaches towards shallow water. — Credit: iNaturalist, CC0.

Fimbristylis cymosa

Fimbristylis cymosa (hurricanegrass) is a sedge species found in salt marshes and mangrove swamps. It can grow up to two feet high, and it is naturalized in Florida. The first documented collection in Florida was in the 1930s, and it has since spread over much of the state. It is native to much of the Americas and Australia, and it may be introduced in Florida.

Where to plant Fimbristylis cymosa

Fimbristylis cymosa should be planted in the salt marsh ecotone between 0.500 and 1.090 meters NAVD88 for best results. It can survive at higher and slightly lower elevations.

Below we provide more detail on where Fimbristylis cymosa plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.3901st Quartile: 0.500Median: 0.700Mean: 0.8213rd Quartile: 1.090Maximum: 2.810

Bar graph of Fimbristylis cymosa counts from plants found in and bordering salt marshes at different elevations. There are relatively few datapoints with s a loose peak around .8 meters.

Fimbristylis cymosa plants grow in the sun by water. A few seedheads grow among wispy blades of grass. — Credit: iNaturalist, CC0.

Flaveria linearis

Flaveria linearis (narrowleaf yellowtops) is an herb species found in salt marshes and marl prairies. It can grow up to two and a half feet high and has long, narrow leaves. It is native to parts of North America and the Caribbean.

Where to plant Flaveria linearis

Flaveria linearis should be planted in the salt marsh ecotone between 0.605 and 1.328 meters NAVD88 for best results. It can survive at a few meters higher elevation, but it should not be planted any lower than this range.

Below we provide more detail on where Flaveria linearis plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.4901st Quartile: 0.605Median: 0.875Mean: 0.9073rd Quartile: 1.328Maximum: 2.040

Bar graph of Flaveria linearis counts from plants found in and bordering salt marshes at different elevations. There is a thin peak at 1.5 meters, and a shorter wider peak spread around .8 meters.

A tangle of Flaveria linearis herb with pale yellow flowers and vibrant green leaves grows on a layer of brown duff. — Credit: iNaturalist, CC0.

Ipomoea sagittata

Ipomoea sagittata (saltmarsh morning-glory) is a vine species found in salt marshes, glades marshes, and hammocks. It is a climbing vine with pink or purple flowers. It is native to the United States southeast, Mexico, and the Caribbean.

Where to plant Ipomoea sagittata

Ipomoea sagittata should be planted in the salt marsh ecotone between 0.660 and 1.065 meters NAVD88 for best results. Some individual plants can survive a few meters higher, but the majority lives in this range.

Below we provide more detail on where Ipomoea sagittata plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −1.2501st Quartile: 0.660Median: 0.840Mean: 0.8793rd Quartile: 1.065Maximum: 3.100

Bar graph of Ipomoea sagittata counts from plants found in and bordering salt marshes at different elevations. There is a peak at .9 meters.

A pink Ipomoea sagittata flower grows from a vine with deep green leaves shaped like an arrowhead. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Iva frutescens

Iva frutescens (bigleaf sumpweed) is a subshrub/shrub species found in salt marsh, beach dune, and salt panne habitats. It can grow almost twelve feet tall and is not very flood tolerant. It is native to the East coast of North America and the Gulf coast of the United States.

Where to plant Iva frutescens

Iva frutescens should be planted in the salt marsh ecotone between 0.525 and 0.933 meters NAVD88 for best results. It should not be planted outside of this range.

Below we provide more detail on where Iva frutescens plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.6101st Quartile: 0.525Median: 0.700Mean: 0.7113rd Quartile: 0.933Maximum: 1.820

Bar graph of Iva frutescens counts from plants found in and bordering salt marshes at different elevations. There is a loose peak centered around .7 meters.

Iva frutescens shrub with green leaves growing in front of a wall of dead stems. — Credit: iNaturalist, CC0.

A patch of Limonium carolinanum with green rounded leaves grows among rafted reed stems on sand. — Credit: iNaturalist, CC0.

Limonium carolinianum

Limonium carolinianum (carolina sealavender) is an herb species found in salt marshes and mangrove swamps. It grows one to two feet high and is often used in flower arrangements. It is native to the East coast of North America.

Where to plant Limonium carolinianum

Limonium carolinianum should be planted in the salt marsh ecotone between 0.460 and 0.900 meters NAVD88 for best results. It can survive at elevations slightly higher than this range but should not be planted any lower.

Below we provide more detail on where Limonium carolinianum plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.7701st Quartile: 0.460Median: 0.650Mean: 0.6663rd Quartile: 0.900Maximum: 1.500

Bar graph of Limonium carolinianum counts from plants found in and bordering salt marshes at different elevations. There is a peak from .2 to 1.1 meters.

A close-up view of Limonium carolinanum stems with white buds and blue flowers. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Lycium carolinianum

Lycium carolinianum (christmasberry/carolina desert-thorn) is a succulent shrub species found in salt marshes and mangrove swamps. It produces small, edible fruits, but may be mistaken for other species whose fruits are not. It is native to the United States.

Where to plant Lycium carolinianum

Lycium carolinianum should be planted in the salt marsh ecotone between 0.385 and 0.950 meters NAVD88 for best results. Some plants survive at higher elevations, but the majority is found in this range.

Below we provide more detail on where Lycium carolinianum plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −1.2501st Quartile: 0.385Median: 0.650Mean: 0.6593rd Quartile: 0.950Maximum: 2.430

Bar graph of Lycium carolinianum counts from plants found in and bordering salt marshes at different elevations. There is a peak from 0 to 1.3 meters centered at .5 meters.

Branches of Lycium carolinianum with dark freen leaves and pink or purple flowers grow on the sand. — Credit: iNaturalist, CC0.

Morella cerifera

Morella cerifera (southern bayberry/wax myrtle) is a tree/shrub species found in salt marshes and other marshes and in hammock habitats. It can grow up to 46 feet high, and the wax that gives it its common name can be used to make candles. It is native to North and Central America as well as the Caribbean.

Where to plant Morella cerifera

Morella cerifera should be planted in the salt marsh ecotone between 0.848 and 1.693 meters NAVD88 for best results. It often grows at higher elevations but should not be planted any lower than this range.

Below we provide more detail on where Morella cerifera plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.5501st Quartile: 0.848Median: 1.120Mean: 1.4063rd Quartile: 1.693Maximum: 7.150

Bar graph of Morella cerifera counts from plants found in and bordering salt marshes at different elevations. There is a peak at 1 meter, and the graph is skewed to the right.

A Morella cerifera shrub with dark green leaves and many small white berries growing directly from the branch. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Muhlenbergia capillaris

Muhlenbergia capillaris (muhly grass) is a grass species found in salt marshes. It can grow up to four feet high and turns pink in the fall. It is native to the United States, Mexico, and parts of Central America.

Where to plant Muhlenbergia capillaris

Muhlenbergia capillaris should be planted in the salt marsh ecotone between 0.875 and 1.450 meters NAVD88 for best results. It can survive at slightly higher and lower elevations but should not be planted much outside of this range.

Below we provide more detail on where Muhlenbergia capillaris plants have been found in and near salt marshes.

Elevation in Meters

Minimum: 0.0001st Quartile: 0.875Median: 1.010Mean: 1.5303rd Quartile: 1.450Maximum: 6.910

Bar graph of Muhlenbergia capillaris counts from plants found in and bordering salt marshes at different elevations. There is a peak at 1 meter, with two outliers between 6 and 8 meters.

A field of Muhlenbergia capillaris grass with scattered patches of pink stretches out with in front of a forest of pines under a sky dotted with white clouds. — Credit: iNaturalist, CC0.

Pluchea odorata

Pluchea odorata (sweetscent) is a subshrub species found in salt marshes and glades marshes. It can grow up to six feet high and is used to make a medicinal tea in some areas. It is native to much of the Americas including the Caribbean.

Where to plant Pluchea odorata

Pluchea odorata should be planted in the salt marsh ecotone between 0.550 and 0.978 meters NAVD88 for best results. It can survive at significantly higher elevations but should not be planted below this range.

Below we provide more detail on where Pluchea odorata plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.4601st Quartile: 0.550Median: 0.765Mean: 0.8193rd Quartile: 0.978Maximum: 2.960

Bar graph of Pluchea odorata counts from plants found in and bordering salt marshes at different elevations. There is a peak around .9 meters.

A close-up view of fuzzy purple Pluchea odorata flower buds. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Sesuvium portulacastrum

Sesuvium portulacastrum (shoreline seapurslane) is an herb species found in salt marshes, mangrove swamps, coastal berms, and glade marshes. It grows up to one foot tall and has long horizontal stems. It is native to much of the world.

Where to plant Sesuvium portulacastrum

Sesuvium portulacastrum should be planted in the salt marsh ecotone between 0.300 and 1.000 meters NAVD88 for best results. Much survives a little lower and a little higher than this range.

Below we provide more detail on where Sesuvium portulacastrum plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −1.4401st Quartile: 0.300Median: 0.630Mean: 0.6633rd Quartile: 1.000Maximum: 3.810

Bar graph of Sesuvium portulacastrum counts from plants found in and bordering salt marshes at different elevations. There is a peak centered at .6 meters.

A Sesuvium portulacastrum herb with pink flowers and red stems grows from the sand. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Solidago sempervirens

Solidago sempervirens (seaside goldenrod) is a forb species found in salt marsh, sand dune, and salt panne habitats. It can grow up to eight feet high and is a succulent species that is currently expanding inland along roadsides. It is native to the United States Atlantic coast and parts of the Caribbean.

Where to plant Solidago sempervirens:

Solidago sempervirens should be planted in the salt marsh ecotone between 0.615 and 1.145 meters NAVD88 for best results. It can survive at higher elevations but should not be planted below this range.

Solidago sempervirens elevations:

Below we provide more detail on where Solidago sempervirens plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.6101st Quartile: 0.615Median: 0.900Mean: 0.8673rd Quartile: 1.145Maximum: 2.320

Bar graph of Solidago semperviren counts from plants found in and bordering salt marshes at different elevations. There is a peak around 1 meter with an even spread on both sides.

Stalks of Solidago sempervirens with broad leaves grow near a muddy field. — Credit: iNaturalist, CC0.

A hand holds a Spartina bakeri inflorescence topped with delicate white tendrils forming the beginnings of flowers. — Credit: iNaturalist, CC0.

Sporobolus bakeri (Spartina bakeri)

Sporobolus bakeri (sand cordgrass), previously known as Spartina bakeri, is a grass species found in salt marshes, marl prairies, and other coastal as well freshwater habitats. It grows up to four feet tall and forms dense bunches. It is native to the United States Southeast.

Where to plant Sporobolus bakeri

Sporobolus bakeri should be planted in the salt marsh ecotone between 0.675 and 1.058 meters NAVD88 for best results. It can survive at significantly higher elevations but should not be planted below this range.

Below we provide more detail on where Sporobolus bakeri plants have been found in and near salt marshes.

Elevation in Meters

Minimum: 0.1801st Quartile: 0.675Median: 0.790Mean: 0.9773rd Quartile: 1.058Maximum: 5.330

Bar graph of Sporobolus bakeri counts from plants found in and bordering salt marshes at different elevations. There is little data, with a peak around 1 meter.

A bunch of Spartina bakeri grows on a hillside. The bottom of the hill is flooded with inches of water. — Used With Permission, Atlas of Florida Plants, USF Libraries.

In the foreground a brown stalk of Sporobolus pumilus, previously known as Spartina patens, grows with narrow inflorescences. Behind, a beach of fine white sand stretches out towards a small sand dune. — Credit: iNaturalist, CC0.

Sporobolus pumilus (Spartina patens)

Sporobolus pumilus (saltmeadow cordgrass/marshhay cordgrass), previously known as Spartina patens, is a grass species found in salt marshes, beach dunes, coastal grasslands, and glades marshes. It grows up to two feet tall in thick mats and is critical to salt marsh health in its native range. It is native to the Atlantic Coast of North America and parts of the Carribean.

Where to plant Sporobolus pumilus

Sporobolus pumilus should be planted in the salt marsh ecotone between 0.345 and 0.983 meters NAVD88 for best results. It is not often found outside this range.

Below we provide more detail on where Sporobolus pumilus plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.5101st Quartile: 0.345Median: 0.665Mean: 0.6123rd Quartile: 0.983Maximum: 1.510

Bar graph of Sporobolus pumilus counts from plants found in and bordering salt marshes at different elevations. There is little data, and it is spread from negative .5 meters to 1.5 meters.

A field of Sporobolus pumilus, previously known as Spartina patens, grass grows densely on a beach. It fades out into white send and then a small berm separating the field from a calm and shallow ocean. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Sporobolus virginicus

Sporobolus virginicus (seashore dropseed) is a grass species found in salt marshes, mangrove swamps, beach dunes, and coastal berms. It grows up to one and a half feet tall and has green or purple flowers. It is native to much of the world.

Where to plant Sporobolus virginicus

Sporobolus virginicus should be planted in the salt marsh ecotone between 0.765 and 1.140 meters NAVD88 for best results. It can grow a little above and below this range.

Below we provide more detail on where Sporobolus virginicus plants have been found in and near salt marshes.

Elevation in Meters

Minimum: 0.1301st Quartile: 0.765Median: 0.960Mean: 1.0373rd Quartile: 1.140Maximum: 2.360

Bar graph of Sporobolus virginicus counts from plants found in and bordering salt marshes at different elevations. There is little data, and it is spread from around .3 to around 2.4 meters.

A wall of Sporobolus virginicus grasses hangs over the sand. The darker green blades of grass fade into paler stalks topped with brown inflorescences higher on the plants. — Credit: iNaturalist, CC0.

Symphyotrichum tenuifolium

Symphyotrichum tenuifolium (perennial saltmarsh aster) is a shrub species found in salt marshes, glades marshes, slough marshes, and upland pine habitat. It can grow to about three feet high and has white yellow or purple flowers. It is native to the United States and parts of the Caribbean.

Where to plant Symphyotrichum tenuifolium

Symphyotrichum tenuifolium should be planted in the salt marsh ecotone between 0.100 and 0.985 meters NAVD88 for best results. It can survive at slightly higher elevations.

Below we provide more detail on where Symphyotrichum tenuifolium plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.7701st Quartile: 0.100Median: 0.565Mean: 0.5673rd Quartile: 0.985Maximum: 1.880

Bar graph of Symphyotrichum tenuifolium counts from plants found in and bordering salt marshes at different elevations. There is little data with no clear peak.

A Symphyotrichum tenuifolium flower sits on a black background. Delicate pink petals fan out from fuzzy yellow anthers. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Yucca aloifolia

Yucca aloifolia (Spanish bayonet/aloe yucca) is a tree/shrub species found in salt marshes and beach habitats like dunes. It can grow up to twenty feet high and has thick evergreen leaves. It is native to the United States Atlantic and Gulf Coasts, Mexico, and parts of the Caribbean.

Where to plant Yucca aloifolia

Yucca aloifolia should be planted in the salt marsh ecotone between 0.660 and 1.560 meters NAVD88 for best results. It can survive at higher elevations and slightly below this range.

Below we provide more detail on where Yucca aloifolia plants have been found in and near salt marshes.

Elevation in Meters

Minimum: −0.2101st Quartile: 0.660Median: 1.130Mean: 1.2343rd Quartile: 1.560Maximum: 5.590

Bar graph of Yucca aloifolia counts from plants found in and bordering salt marshes at different elevations. There is a peak from .2 to 1.8 meters.

A dense field of Yucca aloifolia plants. Bright white bunches of flowers accentuate the green foliage, while a few stalks devoid of flowers speckle the landscape. — Used With Permission, Atlas of Florida Plants, USF Libraries.

Contact

Anna Braswell, (352 846-0865, a.braswell@ufl.edu

Acknowledgements

This restoration guide was created by UF/IFAS Extension with funding from the Florida Climate Institute, the UF/IFAS School of Forests, Fisheries, and Geomatic Sciences, and the UF/IFAS Florida Sea Grant College Program.

Works Cited

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James, M. L., and J. B. Zedler. 2000. “Dynamics of Wetland and Upland Subshrubs at the Salt Marsh–Coastal Sage Scrub Ecotone.” American Midland Naturalist 143:298–311. doi:10.1674/0003-0031(2000)143[0298:DOWAUS]2.0.CO;2.

Kark, S. 2012. “Ecotones and Ecological Gradients,” in Ecological Systems: Selected Entries from the Encyclopedia of Sustainability Science and Technology, edited by R. Leemans. Springer. doi:10.1007/978-1-4614-5755-8_9.

Living Shorelines. 2024. “Wetland Plants Zone.” Virginia Institute of Marine Science. https://ccrm.vims.edu/livingshorelines/ls_wetland_plants_zone.html. Accessed April 2024.

Teal, J. M., and B. L. Howes. 2000. “Salt Marsh Values: Retrospection from the end of the Century.” In Concepts and Controversies in Tidal Marsh Ecology, edited by M. P. Weinstein and D. A. Kreeger. Springer, Dordrecht. doi:10.1007/0-306-47534-0_2.

Wunderlin, R., B. Hansen, A. Franck, and F. Essig. 2021. Atlas of Florida Plants. Institute of Systematic Botany, University of South Florida, Tampa. [SM Landry and KN Campbell (application development), USF Water Institute.] https://florida.plantatlas.usf.edu/.