Dune Restoration and Enhancement for the Florida Panhandle

Beach Mice

Four rare, imperiled subspecies of beach mice occur on the barrier islands and peninsulas of the Florida Panhandle, the Perdido Key beach mouse (Peromyscus polionotus trissyllepsis), the Santa Rosa beach mouse (P. p. leucocephalus), the Choctawhatchee beach mouse (P. p. allophrys), and the St. Andrew beach mouse (P. p. peninsularis) (Figure 5).

With a single exception, these beach mice are endemic to the beaches of the Florida Panhandle—they occur nowhere else in the world. The one exception is the Perdido Key beach mouse, whose range also extends to a small area in Alabama.

Sea Turtles

Our beaches are nesting habitat for the loggerhead sea turtle (Caretta caretta), Kemp’s ridley sea turtle (Lepidochelys kempii), green sea turtle (Chelonia mydas), and sometimes the leatherback sea turtle (Dermochelys coriacea). Both nesting female sea turtles and tiny hatchlings can become disoriented by man-made lights. Bright streetlights and houselights can lead sea turtles inland, away from the Gulf of Mexico, where they become prey to dogs, raccoons, and other animals; die of dehydration; or are maimed and killed by vehicles when they crawl into roads or parking lots. Dunes diminish the impact of city lights and provide a barrier between sea turtle nesting habitat and human developments, thereby encouraging adult and hatchling sea turtles to move toward the Gulf of Mexico.

Gopher Tortoises

While sea turtles use the beaches during nesting periods, the gopher tortoise (Gopherus polyphemus) finds year-round habitat in dunes. Dunes provide burrowing sites for these land animals. Both dunes and interdunal swales, the low depressions between the dunes in the coastal landscape, provide food resources.

Shorebirds

Our beaches and dunes are critical stopover habitats during migration for many birds and pollinators. Three rare shorebirds, the snowy plover (Charadrius alexandrinus), Wilson’s plover (Charadrius wilsonia), and American oystercatcher (Haematopus palliates), nest on the coast of the Florida Panhandle.

Other Beach Dwellers

One of the many migratory pollinators that rely on Florida Panhandle coastal ecosystems is the monarch butterfly (Danaus plexippus). The monarch uses the milkweed (Asclepias humistrata) found on our dunes to deposit eggs and feed larvae for the next generation of butterflies. Rare endemic invertebrates are also found on our coastal landscapes. Three rare beetles, Woodruff’s polyphyllan scarab beetle (Polyphylla woodruffi), the lobed spiny burrowing beetle (Gronocarus autumnalis), and the lobeless spiny burrowing beetle (Gronocarus inornatus), live in the dunes. A rare ground-dwelling bee (Hesperapsis oraria) is also found on our barrier islands and the immediate coastline (Figure 6).

Endemic Plants

Endemic plants such as the two forms of Godfrey’s goldenaster (Chrysopsis godfreyi forma godfreyi and Chrysopsis godfreyi forma viridis), Cruise’s goldenaster (Chrysopsis gossypina subsp. Cruiseana), false rosemary (Conradina canescens), coastal sand frostweed (Crocanthemum arenicola), gulf coast lupine (Lupinus westianus var. westianus), and squareflower (Paronychia erecta) are also associated with coastal landscapes (Figure 7). There are also rare plants such as the largeleaf jointweed (Polygonella macrophylla).

Beach

The beach is a gently sloping landform that extends from the low water line of the Gulf of Mexico to the edge of the first beach dune. Sandy beaches of the Florida Panhandle consist of white, quartz sand. Little or no vegetation is found on the beach.

Along the beach, you can also find wrack—or beach litter consisting of “algae, grasses, driftwood, fruits, seeds, and carrion, along with cultural litter” that accumulates at the high tide line (Behbehani and Croker 1982; Orr et al. 2005; Dugan et al. 2003; Nordstrom et al. 2012). Although wrack is not considered a plant community, it is an important food resource for wildlife such as shorebirds and ghost crabs and should not be removed (Figure 10).

Plants found on the immediate sandy areas of the beach are sandwiched between the Gulf and the first beach dunes (foredunes) and are usually transient residents, meaning they are only present for short time periods. These plants are exposed to the harshest of conditions and exist at the threshold of possible plant survival. One common species often found near or in beach wrack is sea rocket (Cakile species). This plant is an important food source for beach mice, but the plants only live a single growing season. Sea rocket seeds are tolerant of salt water, and the species is dependent on waves and wind to spread the seed.

Beach Dune

Beach dunes are herbaceous plant communities that develop above the high tide line behind sandy beaches (Figure 11). They exist in a uniquely harsh microclimate, characterized by salt spray, heavy winds, tidal fluctuations, and large-scale storm surges. Dune vegetation generally begins at or near high tide with the presence of creeping herbs such as beach morning glory (Ipomea imperati) (Clewell 1986) or mounding herbaceous plants such as beach elder (Iva imbricata). Directly landward are the dune-building rhizomatous grasses, which are essential for the horizontal and lateral growth of dunes. Sea oats (Uniola paniculata) is generally the dominant dune-building grass on foredunes along with bitter panicgrass (Panicum amarum) (Snyder and Boss 2002; Clewell 1986; FNAI 2010). An additional grass, gulf bluestem (Schizachyrium maritimum) is also considered a dune stabilizer and often grows on beach dunes along the Gulf Coast.

Dune-building plants are noted for their ability to grow vertical shoots from their underground modified stems, or rhizomes, in response to sand burial allowing them to tolerate sand accretion. In essence, the dune-building grasses are essential for the formation, growth, and physical stability of beach dunes. Beach dunes dampen sand movement, wind, and salt spray and therefore alter the environment of plant communities found landward.

Coastal Grassland

Coastal grasslands are herbaceous plant communities that exist between beach dunes and inland woody plant communities, such as coastal scrub (Figure 12).

Bluestems (Andropogon species and Schizachyrium species), camphorweed (Heterotheca subaxillaris), and earleaf greenbriar (Smilax auriculata) are characteristic of coastal grasslands. The dune-building grasses like sea oats (Uniola paniculata), bitter panicgrass (Panicum amarum), and marshhay (Spartina patens) are also present on coastal grasslands.

Rare plant species found in coastal grasslands include Godfrey’s goldenaster (Chrysopsis godfreyi), Cruise’s goldenaster (Chrysopsis gossypina subsp. Cruiseana), and gulf coast lupine (Lupinus westianus subsp. westianus). Coastalplain honeycombhead (Balduina angustifolia), the sole nectar source for the endemic coastal plain Hesperapis (Hesperapis oraria), which is also known as the balduina bee and sandhill milkweed (Asclepias humistrata), the food source for monarch butterfly larvae, grow here. Other species that grow in coastal grasslands are spadeleaf (Centella asiatica), LeConte’s flatsedge (Cyperus lecontei), Spanish daisy (Helenium amarum), seabeach evening primose (Oenethera humifusa), squareflower (Paronychia erecta), coastal groundcherry (Physalis angustifolia), Walter’s groundcherry (Physalis walteri), and heartwing dock (Rumex hastatulus).

Coastal Interdunal Swale

Interdunal swales are herbaceous wetlands found in depressions embedded within coastal grasslands or between dunes. Ephemeral swales are seasonally wet for shorter periods of time while permanent swales remain wet (Figure 13). They have a highly variable vegetative composition depending on salt content of the soil, length of time standing water is present during the growing season and conditions at the time seeds germinate and plants establish. (FNAI 2010). Coastal interdunal swales may contain low shrubs such as St. John’s wort (Hypericum species), wax myrtle (Morella cerifera), and yaupon (Ilex vomitoria) in areas where the soil is not always saturated. Inundated portions or deep swales may contain sawgrass (Cladium jamaicense) or black needlerush (Juncus roemerianus).

Scrub

Coastal scrub is the most imperiled ecosystem in Florida (FNAI 2010) and is found on older stabilized dunes (Figure 14). It consists of a dense shrubland of stunted sand live oak (Quercus geminata), Chapman’s oak (Quercus chapmanii), myrtle oak (Quercus myrtifolia), and sand pine (Pinus clausa). Open sandy areas embedded within the oak thickets are an important characteristic, because they provide movement corridors for small mammals and reptiles. Additional plant species found in open sandy areas include Florida rosemary (Ceratiola ericoides), false rosemary (Conradina canescens), October flower (Polygonella polygama), yaupon (Ilex vomitoria), and woody goldenrod (Chrysoma pauciflosculosa).

Bay

Bay County Planning and Zoning Department

850-248-8250

840 West 11th Street

Panama City, FL 32401

Escambia

Escambia County Natural Resources Management

850-595-4988

223 Palafox Place

Pensacola, FL 32502

Franklin

Franklin County Planning and Building Department

850-653-9783

34 Forbes Street, Suite 1

Apalachicola, FL 32320

Gulf

Gulf County Building Department

850-248-8350

840 West 11th St.

Panama City, FL 32401

Okaloosa

Okaloosa County Growth Management, Building Division Inspections - Permitting

Shalimar location:

850-651-7180

1250 Eglin Parkway N, Suite 301

Shalimar, FL 32579

Jim Trifilio, Coastal Management Coordinator

Crestview location:

812 East James Lee Boulevard

Crestview, FL 32539

850-609-5382, 1540 Miracle Strip Parkway SE

Santa Rosa

Santa Rosa County Development Services

850-981-7000

6051 Old Bagdad Hwy, Suite 202

Milton, FL 32583

Walton

Walton County Environmental Resources

850-892-8108

117 Montgomery Circle

DeFuniak Springs 32435

Wrack

Beach wrack is an additional resource that is important to the resilience of beaches and beach dunes. Beach litter consisting of “algae, grasses, driftwood, fruits, seeds, and carrion, along with cultural litter” that accumulates at the high tide line or wrack line after storms is referred to as wrack. Wrack contains resources important to wildlife and aids in the development of beach dunes (Behbehani and Croker 1982; Orr et al. 2005; Dugan et al. 2003; Nordstrom et al. 2012) (Figure 9).

The rough surface of the mixture of materials that make up the wrack catches seeds of dune plants and sand carried by the wind. Trapped seeds germinate and grow with the help of wrack. As wrack decays, it supplies nutrients, protection, and moisture to the plants, potentially increasing the survival and growth of these plants. Seagrasses and algae commonly found in wrack are nitrogen and phosphorous sources for dunes (Williams and Feagin 2010). For these reasons, wrack has an important function in beach ecology and should be left in place (Hooton et al. 2014).

Despite the benefits of wrack, the Florida Fish and Wildlife Conservation Commission (FWC) allows mechanical beach cleaning at some times of the year, which leads to the removal of wrack. Disposal of wrack collected during beach cleaning could squander a valuable resource. Wrack removed by raking can be collected and placed around newly planted sea oats or native dune plants as a natural supplement to enhance growth of dune vegetation. Guidelines for mechanical beach cleaning are available from FWC and include beach cleaning permit conditions and contact information. It is important to note that beach raking also results in loss of new seedlings of sea oats and should be avoided, particularly after storm events.

Uprooted Sea Oats

Uprooted sea oats can be a good source of restoration material. Part of what makes sea oats resilient to the harsh coastal environment is their long underground stems (rhizomes). When these stems are uncovered via erosion, they are often found scattered on the beach or piled up against buildings, remaining trees, and other structures. These scattered stems can be replanted and used for restoration. (Figure 16). Beach homeowners have found, and research has shown, that uprooted sea oats can be used to restore dunes. If immediate action is taken to bury these stems in sand 6–12 in deep, sea oats stems and leaves will likely sprout the following summer (Miller et al. 2003). Typically, with good weather, sea oats must be replanted within 3 to 11 days

after they are uprooted to be successful. Additional planting may be necessary to supplement the re-planted sea oats.

Sand Fence

Installation of sand fence in combination with planting vegetation has been a successful method for dune restoration, but the length and arrangement of sand fencing may be regulated in your area. This is because the use of sand fencing in the Florida Panhandle must follow federal and state regulations enacted to protect nesting sea turtles. Contact your local FDEP field representative for more information and to ensure use of sea-turtle-friendly fencing techniques. If the intended dune restoration area does not allow for the combination of sand fencing and planting, planting alone is preferred.

Where sea turtle nesting is not a concern, many configurations of fencing have been used, but no one fencing configuration has proven to be more successful than another at collecting sand (Miller et al. 2001). The easiest to install, straight fencing parallel to the Gulf, performs as well as several other configurations tested on the Florida Panhandle. It is actually the length of the fence that is the most important characteristic when it comes to sand accumulation. The longer the fence, the greater the sand accumulation. Sand fencing can also provide an additional benefit by deterring people from disrupting planting sites. Consult DEP’s publication Sand Fence Guidelines. To repeat, before designing a dune restoration project that incorporates sand fence installation, be sure to check with a DEP field representative. This will ensure your project does not conflict with sea turtle nesting.

Generally, plants can be transplanted adjacent to sand fences at the time of fence installation. Between buildings and the Gulf of Mexico or gulfward of large dunes, northerly winds are diminished, and sand movement is moderate. In this case, plants can be transplanted near fences. However, in open areas with large amounts of unconsolidated quartz sand and high wind speed, sand movement is rapid, and fences may fill quickly with loose sand. This was seen in areas of complete dune and vegetation loss in the Florida Panhandle after Hurricanes Opal and Ivan. The loose sand should be allowed to settle before plants are installed. Once sand accumulation has slowed, plants may be transplanted on the newly stabilized sand adjacent to the sand fence. An alternative in this situation would be to place plants 15 ft landward and gulfward of fences at time of fence installation (Miller et al. 2001). In this situation, planting further away from fencing allows for both plants and fencing to effectively accumulate sand.

Planting Beach Dune Species

Plants alone are often as effective at accumulating sand as planting in combination with sand fences. Planting on a stabilized beach is preferred.

Sand berms are artificial dunes resulting from dune re-nourishment activities and are often an unstable substrate for establishing plants. It is best after sand placement to allow the sand to stabilize before planting into a berm.

Sea oats are the dominant—but not the only—beach dune species in Florida’s natural dunes. For dunes to provide their many natural benefits, including habitat for wildlife and ecosystem services such as protection for coastal homeowners, it is best if we reestablish dunes that resemble natural, nearby dunes by including the many plants that are found on them.

As a best practice, at least three to four species of herbaceous plants should be considered when restoring beach dunes. After dunes have had several years to grow and the initial plants are established, additional plant species can be added.

Obtaining appropriate plant material can be difficult, especially when using sea oats. Sea oats are protected by various regulations and have genetic and phenotypic variations specific to local populations. Fortunately, sea oats are available at commercial nurseries, but be sure to ask if your stock originates from the Gulf Coast. Sea oats from a population outside of your local area may not grow or flower well. These plants may also interfere with future generations of local sea oats if they do intermix with the local populations through seed production.

The transplant size of grasses and small herbaceous species can vary considerably based on the nursery source. These plants may be grown in a variety of production systems resulting in long, narrow rootballs to short, broad rootballs depending on the dimensions of the production containers.

A common practice among producers is to remove the plants from the production containers and pack only the plants without their production containers in a box for shipping. When plants remain in their original production systems, the restoration manager has the option to hold the plants for a longer period of time between delivery to the restoration site and planting. These plants may be easily watered and have good air movement between the leaves. A quick review of the terms of sale and shipping options in addition to the plant materials available from a grower before ordering will provide much of this information. Otherwise, plants combined in a shipping box without pots must be planted quickly. Also, the heat the plants generate from within the shipping containers can be detrimental.

Plantings for the establishment of new dunes should be as far landward as possible. The most successful restoration along the Florida Panhandle has taken place where vegetation was planted at least about 300 ft inland of the mean high tide line. This may not be possible in areas of coastal development. When possible, new dunes should fill large gaps between fragmented dunes. This will increase plant survival and allow for natural redevelopment toward the Gulf of Mexico.

What, where, and when to plant are the most commonly asked questions in regard to beach plantings to establish dunes. For the Florida Panhandle, sea oats (Uniola paniculata), bitter panicgrass (Panicum amarum), beach elder (Iva imbricata), and sometimes gulf bluestem (Schizachyrium maritimum) are the most commonly planted species when planting beach dunes nearest the Gulf.

A diversity of plants is preferred for many reasons, including food and habitat for wildlife. However, these plants should not be intermixed within the same row or zone. Sea oats will completely replace bitter panicgrass within one to two years if planted immediately adjacent to each other. Instead, planting in blocks or rows of each species maintains the diversity of the planting for a longer period of time (Figure 17).

We are recommending four planting zonation patterns because these patterns have resulted in greater survival, plant growth, and sand accumulation in recent studies (Stoddard et al. 2014). The first two suggested planting schematics include (beginning nearest to the Gulf of Mexico) several rows of bitter panicgrass. The first recommendation is then to follow the planting of bitter panicgrass with beach elder immediately landward, sea oats landward of beach elder, and gulf bluestem behind all other species (Figure 18).

Another combination is to plant bitter panicgrass followed by sea oats, gulf bluestem, then beach elder as the most landward.

Two other patterns of planting beach dune vegetation have proven successful. Both include sea oats as the plant species closest to the Gulf of Mexico and beach elder as the furthest from the Gulf of Mexico.

One suggestion is to plant the first several rows (three or more) with sea oats nearest to the Gulf of Mexico, rows of bitter panicgrass landward of sea oats, followed by gulf bluestem, then beach elder.

The second suggestion is to plant gulf bluestem landward of sea oats, bitter panicgrass landward of gulf bluestem, and beach elder on the back row or back several rows. Beach elder can also be planted in a large block well out in front of all other species, but it does not do as well when planted as the first row of plants with other species immediately landward.

If the objective of the restoration project is to build sand quickly, these planting combinations accumulate sand at a similar rate to monocultures of sea oats or bitter panicgrass. It should be noted that gulf bluestem and beach elder both have higher survival when planted behind either sea oats or bitter panicgrass, or when planted alone. Any of these planting patterns promote plant survival and dune growth.

Recommended Plant Spacing

Recommendations for spacing of beach plants vary. For sea oats, place plants from 1 to 5 ft apart depending on plant size and the restoration objective. One strategy is to have a lower density closer to the water and higher density as the planting extends landward (Figure 19). The example shown here places plants about 36 in apart nearest the Gulf and then decreases spacing to 18 in, finally decreasing spacing to 12 in apart at the most landward portion of the planting as the rows of plants move away from the Gulf of Mexico.

This allows for wider dune development because sand can then move into all parts of the project area. If the plants nearest the Gulf of Mexico are planted too densely, sand moving from the beach landward will be trapped in the first few rows, preventing the back of the planting from receiving sand. Larger plants, such as 4-inch pots, can be spaced farther apart than smaller ones.

Recommended Planting Depth

Dune plants are quite tolerant of deeper burial in the sandy beach soil. In fact, planting too shallow is the most common cause of plant death. The top layer of the quartz sand of the Florida Panhandle dries very quickly after rain. Moisture increases with depth, and deep planting allows the roots to stay in contact with the moisture as they grow into the sand. Sea oats and bitter panicgrass should be planted so that the top of the rootball is at least 6 in below the beach surface. If transplants have short leaves, plant to a depth where at least 3 in of the foliage is above the beach surface.

For other beach grasses and herbaceous and woody plants, place the rootball deep enough to access the available soil moisture (Figures 20 and 21). Note how the dry sand above the moist sand can easily be identified. This demonstrates how dry the upper 4–6 in of sand can be only 12 hours after a heavy rain.

The planting depth may differ based on the species and the size of the production container (Figure 22). Each of these plants grown and marketed as a 4-inch transplant represent differing container dimensions.

Container depth may have a direct impact on the rooting depth of the transplant. Deeper pots provide a deeper rooting profile for the transplants. As a general rule, try to place a few inches of beach sand above the rootball at planting. Many production substrates are coarser in texture than the beach sand, and the wind will cause these substrates to dry very quickly if they are not covered. Be sure to completely fill the hole around the plants with sand. Air trapped in the planting hole will prevent the roots from growing into the native sand and decrease the chance the plant will survive.

Planting Amendments

Wheat Straw

The potential of using organic substances similar to beach wrack to enhance growth of dune vegetation has been tested in the Florida Panhandle. A layer of wheat straw approximately 8 in deep around transplanted sea oats will increase sea oats growth and sand accumulation (Figures 23 and 24). If sea oats are transplanted during dryer months, survival may also increase with the use of wheat straw. (Hooton et al. 2014). Wheat straw has been tested with sea oats, but further research is needed before this procedure can be recommended for other species.

Fertilizer

A variety of fertilization protocols exist for newly transplanted and established sea oats, but there has been little information available to verify the need or effectiveness of fertilizer additions.

Slow-release fertilizer can initially be added to new plantings, but continuous fertilization is not necessary due to adaptation of sea oats to extreme nutrient-deficient sites. Florida DEP specifications for restoration projects in Walton County include the addition of ½ teaspoon of Osmocote® 18-6-12 at the time of planting, which releases nutrients over a period of 90 days.

Water Adsorbing Gel Products

Water adsorbing polymer gel products such as Terrasorb®and Stock-osorb®, used at a rate between 8 and 12 ounces of hydrated gel per transplant have also been recommended at the time of planting (USDA-NRCS) to assist with water availability. Recent investigations using woody plants with and without the addition of an adsorbing polymer gel product did not demonstrate a significant improvement in plant survival or growth (Miller et al. 2013). Further work is needed to determine if these products are indeed beneficial to the establishment and growth of beach plants.

Planting Woody Species after Beach Dune Establishment

Scrub vegetation, including sand live oak (Quercus geminata), myrtle oak (Quercus myrtifolia), yaupon (Ilex vomitoria), and Florida rosemary (Ceratiola ericoides), frequently grows on the leeward side of large, well-developed beach dunes, scattered in association with coastal grasslands and coastal interdunal swales, and on back-barrier dunes (Figure 25). These woody plants have been found to further stabilize dunes. Dunes with woody plants are more likely to survive strong storms (Pries et al. 2009).

Additional woody species such as wax myrtle, yaupon, and salt bush (Iva frutescens) are found in swales within coastal grasslands (Figure 26). The fruits of these woody plants are also critical to beach mice and other coastal wildlife, particularly in the winter and spring following strong storms. Thus, replacement of these species to our coastal landscapes is important.

Woody species should not be placed too close to the Gulf of Mexico in order to reduce exposure to salt spray. A good rule of thumb is to wait until at least two to three small beach dunes have redeveloped before incorporating woody species into a dune restoration project. Generally, these woody species should be planted at least 560 to 670 ft landward of the Gulf of Mexico or behind well-developed beach dunes (Thetford et al. 2005; Thetford et al. 2015).

Herbaceous and woody plants grown for restoration purposes may be produced in a variety of containers using a variety of production substrates. The appropriate size of transplant for a given site will depend upon factors such as the size of the shoot and root and the relationship of both components. The production system may vary based on the restoration site soil characteristics, relative soil moisture, and the tolerances of a given species to conditions such as drought or salt stress. Nursery-grown plants are exposed to minor water and heat stress at the end of the production period to assist with the transition from a nursery setting to the harsh conditions of a restoration site. Examples of container systems we have used to produce plants for coastal restoration trials include 3-gallon and 1-gallon tall pots, and standard gallon or quart nursery containers (Figure 27).

Woody plants grown in proportionally tall pots, or treepots, with well-developed root systems do the best (Figure 28). Planting should be conducted during the spring or fall. Two years after planting, survival of inkberry holly (Ilex glabra) produced in standard 1-gallon pots was 32 percent, while survival of inkberry holly produced in 1-gallon tree pots was 65 percent (Thetford et al. 2005). Unless the location has exceptionally high winds and sand accumulation, deep planting should be used. This means the top of pot will be 6–8 in below the surface of the sand.

If high winds and sand erosion are a problem at a site, deep planting will help prevent the uprooting of plants. Additionally, placing a portion of the roots in soil with a higher moisture content may aid plant establishment.

Apocynaceae

Sandhill milkweed is scattered on backdunes, in sandhills, and often in disturbed areas, such as mowed roadsides. It has a range in Florida south to Lake Okeechobee and also occurs in coastal southeast states west to Louisiana and northeast to North Carolina.

The larvae of monarch butterflies are entirely dependent on native milkweeds as a food source for survival, and several studies have identified sandhill milkweed as a monarch butterfly sustainer. Monarchs feed on the leaves of sandhill milkweed, which contain a steroid toxic to predators of milkweeds. Milkweed bugs (Oncopeltus) are also dependent on milkweeds, stalking and feeding almost entirely on milkweed seeds. Several other pollinators, including bees and other butterflies, visit this plant.

General Description

Sandhill milkweed is a deciduous perennial usually less than 3 ft tall. Plants form tuberous (thickened) roots and may become dormant at varied times during the warmer months as well as during the winter. Stems are prostrate to ascending.

Leaves are simple and oppositely arranged. They are "sessile," which means that they lack stalks, and the leaf bases clasp the stem. Leaves are green to green with purple and 2 to 5 in long. Leaves have a glabrous (smooth) surface and prominent pink to maroon veins.

Inflorescences (flower groups) are umbels (attached at a single point like the frame of an umbrella) with white to pink to lavender flowers on pedicels (stalk of a single flower) and occur terminally or in leaf axils during spring to summer with sporadic flowering through fall. Flowers are typical of the genus with calyces and corollas having 5 reflexed lobes; corollas can be up to 7 mm long. Within each flower, pollen is produced and the many grains of pollen fuse together in a special, sack-like structure called a pollinium that is transferred by pollinators as a single unit.

Fruits are follicles 3 to 6 in long containing brown seeds with an attached coma (white, floss-like fiber) that facilitates wind dispersal. All seeds from a single follicle are likely pollinated with pollen from the same pollonium. This plant exudes a milky sap when tissue is punctured.

Propagation

Campbell (2016) describes sandhill milkweed seed collection, storage, and germination as follows. Seeds should be collected when the follicle is dehisced (splits open) or when it dehisces upon the slight application of pressure, typically with a large seed crop in late May and continuing sporadically throughout the summer. If seeds are not immediately germinated, they should be allowed to air dry for 2 weeks before storage in airtight containers at room temperature. Seeds remain viable for at least 18 months in storage.

Seeds are non-dormant at time of collection with optimal germination temperatures between 24 and 28°C.

Seeds germinate in light but may prefer dark. Viability of seeds is variable but can reach near 100%. Seeds can be germinated with high success in seedling flats. Seedlings have been grown with limited success in 40-cell plug flats, 4-in pots, and 1-gal pots in a greenhouse and outdoors with a standard fertilizer and overhead irrigation. This plant is vulnerable to damping off, aphids, and thrips during greenhouse production and aphids and monarch butterfly larvae during outdoor production. Greenhouse growers report diminishing plant quality after seedlings achieve growth of a few to several nodes.

Though no published cutting propagation protocols are available for Asclepias humistrata, other milkweeds are known for their ability to be propagated from root cuttings (Landis 2014; Luna and Dumroese 2014). Use a well-drained substrate and natural photoperiod to grow this plant. Cutting propagation results in a clonal population and is not recommended for this species.

Asteraceae

Coastalplain honeycombhead is found in beach dunes, coastal grasslands, and scrub throughout Florida and into Alabama and Mississippi. It is a prolific flower and seed producer that attracts numerous pollinators, including the gulf fritillary butterfly. Interestingly, the endemic, solitary, and ground-dwelling coastal plain Hesperapis (Hesperapis oraria), also known as Balduina bee, is completely dependent on the coastalplain honeycombhead for survival, only emerging from the ground a few weeks each year in September to October to collect pollen and nectar (Hunsburger 2013). This bee only occurs on barrier islands and peninsulas in the northern Gulf of Mexico (Hunsburger 2013) and is particularly vulnerable to climate-change-driven sea-level rise and habitat fragmentation.

General Description

Coastalplain honeycombhead is an herbaceous, widely branched annual to biennial that can reach heights of 1 meter but often is much shorter in coastal plant communities. Leaves are entire, simple, narrowly linear, up to 2 in long, and alternate. Inflorescences occur en masse during the summer. Inflorescences are branched corymbs when not solitary. Heads contain ray flowers up to 0.8 in long with yellow rays and disk flowers up to 4 to 5 mm long, also yellow. When dry, mature heads are viewed from above, chambers in the head take on the appearance of cells in a honeycomb. Chambers appear white and contain easily identifiable fruits. Fruits are achenes typically no longer than 2 millimeters. Seeds are black with an attached whitish grey 2-mm-long pappus with round scales.

Propagation

Cutting propagation of coastalplain honeycombhead is possible with an application of 5,000 ppm IBA (Indole-3-butyric acid) recommended for optimal rooting response. Apical stem cuttings taken during June to July should achieve at least 80% rooting and produce about 15 roots per cutting (Wilson et al. 2010).

Propagation from seed has also been studied. Seeds of coastalplain honeycombhead are physiologically dormant and need a period of cold stratification for germination (Pérez 2007; Wilson et al. 2010). Seeds possess a non-deep physiological dormancy and have up to 80% germination with exposure to alternating day/night winter temperatures of 22/11°C for about 4 to 5 weeks. Natural germination should occur in the spring.

Seedlings can be grown in greenhouses. The following is adapted from Smith et al. (2014) for the production of plants in 1-gal pots for ornamental plantings. Transplants may be placed in smaller containers for a shorter production period if used for reestablishment of this species for restoration purposes.

Plant seeds in germination media within 6-cell packs where they can remain for 4 weeks or until they form cohesive rootballs. Plants may be transitioned to outdoor, full sun culture and moved up to 1-gal pots within a well-drained media, such as Atlas 7000, for an additional 16 weeks of production. Production in smaller containers or production of smaller vegetative transplants for restoration plantings will shorten the production period.

Outplanting

This species has successfully been transplanted (20-week-old seedlings) from a container (1-gal pot) when grown in a well-drained substrate (Atlas 7000), and performed well in a trial garden as a native wildflower producer for several months (Smith et al. 2014). This species is an annual and needs to be transplanted early in the growing season so it is established before floral initiation. The species is also known to be an obligate outcrosser. Multiple plants will need to be established in close proximity to ensure pollination among container-grown plants to encourage seed production and natural recruitment the following season in the restoration area where planted.

Literature Cited

Hunsburger, H. 2013. "Distribution and habitat use of Florida endemic solitary bee Hesperapis oraria and host plant Balduina angustifolia." Master's thesis. University of Florida.

Pérez, H.E. 2007. Final Report FWAC Grant #R-006-06. 3 p. Smith, A.M., S.B. Wilson, M. Thetford, K.L. Nolan, and C. Reinhardt Adams. 2014. "Performance of nine Florida native wildflower species grown in varying container substrates." Native Plants Journal 15(1):75–86. https://doi.org/10.3368/npj.15.1.75

Wilson, S.B., H. Perez, and M. Thetford. 2010. Propagation, Production, and Landscape Evaluation of Native Wildflowers in West, Central and South Florida. Condensed Progress Report for the Florida Wildflower Foundation. https://www.flawildflowers.org/wp-content/resources/pdfs/Research/Wildflower%20year-end%20progress%20report-Wilson%20et%20al.pdf

Ericaceae

Florida rosemary is important in maintaining back dune structures and is found inland in scrub communities. This plant is found throughout scrub plant communities in Florida, and more broadly is found west to Mississippi and east to South Carolina in xeric soils and in communities with fire return intervals of 20 to 40 years. Plants are killed by fire and storm surge events, but seeds germinate readily post-disturbance. Its fruit is an important food source for wildlife but is not produced until plants are at least 12 years old.

General Description

Florida rosemary is a monotypic evergreen shrub that can reach heights of 6 ft. The shrub has a rounded form and is densely branched. Stems have shredding, gray bark with rough leaf scars when several years old while young stems are pubescent. Leaves are simple, dark green, so strongly revolute they appear needle-like, linear, 8 to 12 mm long by 1 mm wide. They grow in whorls of 4 or 6 in distinct rows when viewed from the stem apex but are opposite. They smell like rosemary when crushed. Inflorescences occur from spring to fall and individual plants have very small male or female flowers clustered at leaf axils. Flowers are yellow to brown, and the plants are dioecious (male and female flowers occurring on separate plants). Fruits are round, fleshy drupes with a 3-mm diameter. They are yellow to green and contain 2 seeds.

Propagation

The following cutting propagation protocol is adapted from Thetford et al. (2001). Softwood stem cuttings produce roots in course propagation substrates such as perlite:vermiculite (1:1) or pinebark:sand (6:1). Cuttings taken from stem tips should be around 3.5 in long with the bottom ½ inch of foliage removed. The base of the cutting should be exposed to auxin treatments below 5,000 ppm to improve root qualities such as root number and root length. Cuttings take several (8 to 12) weeks to initiate roots under intermittent mist; hence this xeric plant may require fungicide applications (drenches) to reduce root zone pathogens that may cause root rots. Cuttings should be propagated in flats with multiple cells such as 72-cell flats to allow transfer outdoors for production.

Florida rosemary has roots with a very small diameter and adventitious roots of cuttings may be weakly attached to cuttings. Retaining rooted cuttings in the initial propagation flats and allowing several months of outdoor production before attempting to transplant them to production containers will improve retention of the newly formed root systems.

Cuttings can be transferred to production containers such as 4-in, 1-qt or 1-gal pots with an amended 100% pine bark substrate and grown outside with overhead irrigation (Miller et al. 2008).

Propagation from seed is slow but can be done. Johnson (1986) developed the following technique. Collect fruits from December through March and let them air dry for at least a week. Scarifying seed with sandpaper speeds up germination to 6 months rather than 8 or 12 months. Plant the seeds in a large pot (at least 6 in) with a well-draining substrate, and water them as needed. Seedlings are very small at germination and will require a very long production period to reach transplant size.

Outplanting

This species should be restricted to areas with minimal disturbances similar to the areas where it occurs naturally. One-and-a-half-year-old plants grown in 1-gal pots from stem cuttings have been planted with success behind two to three embryo dunes (1.6 to 3.3 ft in height) at least 560 ft from the Gulf of Mexico (Miller et al. 2008). This species was sensitive to higher levels of salt spray and higher wind speeds when placed closer to the Gulf. Do not use seedlings that are less than one year old (Johnson 1986).

Literature Cited

Johnson, A.F. 1986. "Recipe for growing Florida rosemary, Main Ingredient: Patience!" Palmetto Spring 5.

Miller, D.L., M. Thetford, and M. Schneider. 2008. "Distance from the gulf influences survival and growth of three barrier island dune plants." Journal of Coastal Research 24(3):261–266. https://doi.org/10.2112/07-0914.1

Thetford, M., D.L. Miller, and P. Penniman. 2001. "Vegetative propagation and production of Ceratiola ericoides Michx. for use in restoration." Native Plants Journal 2(1):116–125. https://doi.org/10.3368/npj.2.2.116

Asteraceae

Woody goldenrod is found in beach dunes, scrub, and sandhill plant communities. It occurs in the Panhandle of Florida and more broadly in the southeastern United States west to Mississippi and northeast to North Carolina. This plant may leach chemicals into the soil that inhibit seed germination of gulf bluestem (Schizachyrium scoparium var. scoparium) (Fischer et al. 1994). Woody goldenrod is an underused landscape plant with a prolific fall color from flowers that attract numerous pollinators.

General Description

Woody goldenrod is a multibranched, evergreen sub-shrub that can reach heights of 3.3 ft or more. Stems are glabrous, numerous, ascending, and round in cross section. Stems bearing flowers and fruits extend far beyond vegetative stems. Leaves are sessile (without stalks), simple, 0.75 to 2.5 in long, alternate, elliptic to oblong, and grayish green with an entire margin. Inflorescences are heads that are sticky, borne in clusters, and numerous, with a single outer row of yellow ray florets. They occur from late summer to fall. Fruits are hard, dry, pale, bristled achenes.

Propagation

Cutting propagation of woody goldenrod is easily accomplished with terminal stem cuttings. Nonbranched, vegetative apical stem cuttings from summer softwood or winter hardwood root without auxin, but a 5,000 ppm IBA (Indole-3-butyric acid) application will increase root numbers and root length (Wilson et al. 2010). Propagation from seed for woody goldenrod has been accomplished with wild-collected seed. Seeds prefer cooler temperatures (20/10°C alternating day/night temperatures) to warmer ones (Wilson et al. 2010).

Outplanting

Rooted cuttings or seedlings may be grown in a variety of coarse production substrates and a variety of container sizes. Smith et al. (2014) produced woody goldenrod in substrates such as Atlas 3000, Atlas 7000, Fafard 3B, and Metro Mix 300 while the authors have grown them in a 100% pine-bark substrate amended with lime and slow-release fertilizer. Plants grown in 1-gal containers were evaluated for potential use in home landscapes with high transplant success (Smith et al. 2014). Peak flowering for the trial plants occurred in November.

Literature Cited

Fischer, N.H., G.B. Williamson, J.D. Weidenhamer, and D.R. Richardson. 1994. "In search of allelopathy in the Florida scrub: the role of terpenoids." Journal of Chemical Ecology 20(6)1355–1380. https://doi.org/10.1007/BF02059812

Smith, A.M., S.B. Wilson, M. Thetford, K.L. Nolan, and C. Reinhardt Adams. 2014. "Performance of nine Florida native wildflower species grown in varying container substrates." Native Plants Journal 15(1):75–86. https://doi.org/10.3368/npj.15.1.75

Wilson, S.B., H. Perez, and M. Thetford. 2010. "Propagation, Production, and Landscape Evaluation of Native Wildflowers in West, Central and South Florida, 2010 Condensed Progress Report." https://www.flawildflowers.org/wp-content/resources/pdfs/Research/Wildflower%20year-end%20progress%20report-Wilson%20et%20al.pdf

Outplanting

Sandhill milkweed is an obligate outcrosser, and, therefore, monocultures (clonal populations resulting from vegetative propagation) for restoration projects are discouraged. Clonal populations may eliminate the potential for outcrossing necessary for seed production. Seedlings (12 months) from 40-cell flats were successfully planted in an outdoor research plot on a historic sandhill pine plant community with over 50% survival. Plant survival was similar after 1 year with or without supplemental fertilizer or irrigation.

Literature Cited

Campbell, G. 2016. "Dormancy and germination characteristics of two Florida native forbs, Asclepias humistrata and Lupinus diffusus." Masters thesis. University of Florida.

Landis, T.D. 2014. "Monarch waystations: propagating native plants to create travel corridors for migrating monarch butterflies." Native Plants Journal. 15(1):5–16. https://doi.org/10.3368/npj.15.1.5

Luna, T., and R.K. Dumroese. 2013. "Monarchs (Danaus plexippus) and milkweeds (Asclepias species): the current situation and methods for propagating milkweeds." Native Plants Journal. 14(1):5–15. https://doi.org/10.3368/npj.14.1.5

Asteraceae

Two species of goldenaster are found on beach dunes within the western Panhandle of Florida (FNAI 2000). Chrysopsis gossypina subsp. Cruiseana (Cruise's goldenaster) and Chrysopsis godfreyi (Godfrey's goldenaster), which is further differentiated into two morphologically distinct forms, Chrysopsis godfreyi f. godfreyi (pictured below right) and Chrysopsis godfreyi f. viridis (pictured below left).

Both forms of Chrysopsis godfreyi and Chrysopsis gossypina subsp. Cruiseana share many morphological similarities and co-occur in coastal plant communities. They are presented together to provide distinguishing characteristics among the these species. A summary table of vegetative characteristics and photos is also provided.

General Descriptions

Propagation

Reproduction from seed was studied by Hooton (2011) to characterize seed production and germination requirements for these Chrysopsis from native populations in Escambia County, Florida. From mature flowers collected in a native setting, a range of 6,000 to 8,000 seeds was recorded per plant. In growth chamber studies, seed were shown to need light to germinate, and all three could be successfully germinated at alternating day/night temperatures of 30/20, 25/15, and 20/10°C to achieve 50 to 70% germination. Wild-collected seed may be thrashed from dried heads and sown directly in open flats without grading or further cleaning. Seedlings emerge within 3 weeks and can be transplanted to liner production flats or small pots and grown outdoors. Smith et al. (2014) produced landscape-quality transplants from seed in a variety of production substrates.

Vegetative propagation is also possible for Chrysopsis if terminal stem cuttings are collected during short days while plants remain vegetative.

However, once critical day length triggers floral development, the cuttings may root but will only produce inflorescences that have no ability to form subsequent vegetative growth. Cuttings will root readily within 7 days without supplemental auxin and should be removed from overhead mist as soon as roots are detected. The resulting rooted cuttings may be potted in standard, well-drained potting mix in 4-in pots and will be ready for outplanting within 4 to 6 weeks when rootballs have grown sufficiently to hold together.

Outplanting

The authors have successfully planted all of these Chrysopsis from plants that filled 4-in pots that were propagated from either seedlings or rooted cuttings. Greatest outplanting success was achieved in late January with near 100% survival 4 months after planting. Plants were outplanted on backdunes midslope at least 12 in from each other and existing perennial grasses. Fertilizer (½ tsp Osmocote 18-6-12) application at the time of planting improved the aesthetic and increased biomass for these plants but was not necessary for survival.

References

Hooton, N. 2011. "Restoration strategies for improving survival and composition of plant species native to coastal dunes in the Florida Panhandle." Master's Thesis, University of Florida.

Smith, A.M., S.B. Wilson, M. Thetford, K.L. Nolan, and C. Reinhardt Adams. 2014. "Performance of nine Florida native wildflower species grown in varying container substrates." Native Plants Journal 15(1):75–86. https://doi.org/10.3368/npj.15.1.75

Florida Natural Areas Inventory (FNAI), 2000. Field Guide. Godfrey's goldenaster. https://www.fnai.org/PDFs/FieldGuides/Chrysopsis_godfreyi.pdf

Lamiaceae

False rosemary is found on the backsides of foredunes, on all sides of backdunes, and inland in scrub communities. False rosemary is killed by fires but will reseed to an area in the absence of further disturbance. It is endemic to west Florida and Alabama, contributes to beach mouse habitat, and attracts many pollinators.

General Description

False rosemary is an evergreen sprawling sub-shrub that can reach heights and widths of 3 ft.

Stems are pubescent and spreading or erect. Leaves are simple, linear, pubescent, oppositely arranged, and gray. They grow up to ½-inch long, and they smell like mint when crushed. Inflorescences are solitary, axillary, and zygomorphic (two-lipped) with 4 stamens. They have lavender to white corollas with dark spots on the lower lip occurring from March to November. Fruits contain 4 nutlets.

Propagation

Softwood cuttings can be used for asexual propagation. The following protocol is adapted from Thetford and Miller (2002 and 2004). Four-inch nonbranched terminal shoots should be taken during the growing season. Auxin application improves root number and root length of cuttings. Remove the basal ½ in of foliage and quick dip in liquid auxin for one second or stick the basal ½ to ¾ in of the cutting into auxin talc powder. Root cuttings in 72-cell flats under mist for 3 to 4 weeks followed by hand watering for another 2 to 3 weeks in a well-draining substrate such as 100% pine bark. Cuttings will benefit from fertigation with a complete fertilizer solution providing nitrogen at a rate of 150 ppm 1 to 2 times a week before transplanting to larger containers.

Plants can be pruned to stimulate branching starting week 4 before or after transplanting to larger pots. Plants perform well in 4-in and 1-qt pots and require 4 to 6 weeks to develop a full rootball and a canopy of 6 to 8 in.

No published information on germination of false rosemary is available. A related species that grows in colder climates, Conradina verticillata, has been shown to require cold stratification (12 weeks at 5°C) to alleviate seed dormancy and light to germinate (Albrecht and Penagos 2012). The authors have noted frequent occurrence of Conradina canescens seedlings in the bare soils and neighboring pots of the nursery production area, suggesting the species will recruit readily from seeds once introduced to an area.

Outplanting

The authors have transplanted false rosemary from 4-in pots to protected back dune and scrub areas with high success. However, tender plants from nursery production areas are very sensitive to high winds and salt spray, suggesting transplants from nursery stock may need to be restricted to areas with less wind and salt spray.

Literature Cited

Albrecht, A.A., and J. C. Penagos Z. 2012. "Seed germination ecology of three imperiled plants of rock outcrops in the southeastern United States." The Journal of the Torrey Botanical Society 139(1):86–95. https://doi.org/10.3159/TORREY-D-11-00066.1

Thetford, M., and D.L. Miller. 2002. "Propagation of four Florida coastal dune species." Native Plants Journal 3(2):112–120.

Thetford, M., and D.L. Miller. 2004. Propagation and Production of Gulf Bluestem. ENH973. Gainesville: University of Florida Institute of Food and Agricultural Sciences. https://doi.org/10.32473/edis-ep231-2004

Williamson, G.B., N.H. Fischer, D.R. Richardson, and A. Peña. 1989. "Chemical inhibition of fire-prone grasses by fire-sensitive shrub, Conradina canescens." Journal of Chemical Ecology 15(5):1567–577. https://doi.org/10.1007/BF01012384

Cistaceae

Coastal sand frostweed is found on beach dunes, scrub, and sandhills. It is endemic to the Florida Panhandle, Mississippi, and Alabama coastal counties. After Hurricane Katrina, coastal sand frostweed became the plant with highest frequency on stable dunes on Horn Island, Mississippi (Lucas and Carter 2013).

General Description

Coastal sand frostweed is an herbaceous, perennial groundcover species. Leaves are alternate and simple, and have pubescence that conceals the leaf surface. Inflorescences are terminal umbellate clusters that occur during spring. Flowers have radial symmetry and are 10 to 20 mm wide with 5 bright yellow petals. Fruits are pubescent twovalved capsules.

Propagation

Apical stem cuttings (6–8 cm) collected in early April from Santa Rosa Island rooted readily under intermittent mist within two weeks in a climate-controlled greenhouse. Rooted cuttings formed complete rootballs in 72-cell flats in less than 7 weeks.

Mature plants may be divided and potted in a coarse potting mix, but survival with this method has only been 50%. Larger divisions have survived in container production with more success than smaller divisions.

Seed germination information is presently not available for coastal sand frostweed, although the authors found non-scarified seeds don't imbibe water (i.e., seeds are physically dormant). Other Helianthemum species have been reported to have physical dormancy as well (Pérez-García and González- Benito 2006; Thanos 1992).

Outplanting

No published outplanting information is presently available for coastal sand frostweed.

Literature Cited

Lucas, K.L., and G.A. Carter. 2013. "Change in distribution and composition of vegetated habitats on Horn Island, Mississippi, northern Gulf of Mexico, in the initial five years following Hurricane Katrina." Geomorphology 199:129–137. https://doi.org/10.1016/j.geomorph.2012.11.010

Pérez-García, F., and M.E. González-Benito. 2006. "Seed germination of five Helianthemum species: Effect of temperature and presowing treatments." Journal of Arid Environments 65:688–693. https://doi.org/10.1016/j.jaridenv.2005.10.008

Thanos, C.A., K. Georghiou, C. Kadis, and C. Pantazi.1992. "Cistaceae: a plant family with hard seeds." Israel Journal of Botany 41(4–6):251–263.

Chrysobalanaceae

Gopher apple occurs from the lower Florida peninsula northward to South Carolina westward to Louisiana in coastal dunes, sandhills, and disturbed areas such as roadsides. Gopher apple gets its name because gopher tortoises, along with other small mammals, eat their fruit. Gopher apple is an ideal groundcover for a coastal landscape with well-draining soil and a low pH (Gilman 2014).

General Description

Gopher apple is a low-growing, clonal, evergreen shrub reaching heights of less than 1.6 ft that spreads via stout underground stems. Leaves are alternate, simple, elliptic to spatulate, and grow from 0.8 to 4 in long by 0.4 to 1.6 in wide. They are largest at midstem compared to upper and lower stem, glabrous or pubescent below, with shallowly undulate to entire margins. Leaves superficially resemble the leaves of oaks. Stems are stout, woody, underground, and give rise to aerial shoots. Flowers are white, borne in terminal clusters, and commonly extend past the leaves. They are inconspicuous and appear from April to summer.

Fruits are single-seeded drupes. They are fleshy, ellipsoid, dark purple to yellow (rarely white), and 0.4 to 1.6 in in diameter. Plants with reddish new growth typically produce purple fruits while plants with greenish-white new growth typically produce yellow to white fruits.

Propagation

Gopher apple seeds are not dormant and can be easily used for propagation with nearly 100% germination of viable seed (Wilson et al. 2010). Gopher apple prefers warmer alternating temperatures (30/20 and 35/25°C vs 25/15 and 20/10°C) when exposed to a 12-hour photoperiod (Wilson et al. 2010). Seedlings have performed well in a peat-based potting mix (Fafard 3B) when grown in a greenhouse (Smith et al. 2014).

Cutting propagation (softwood cuttings) of gopher apple is possible without the application of auxins, but auxins may increase rooting percentage to near 100% (Wilson, Pérez and Thetford, 2010). Cuttings may be taken in May or June before stems become woody. Place cuttings under intermittent mist with natural photoperiods.

Rooted cuttings failed to overwinter when new growth was not present before winter dormancy. More information on subsequent growth of rooting cuttings is needed.

Outplanting

Transplanting gopher apple is known to be difficult in the wild, but it should establish from nursery-grown plants (Gilman, 2014). Greenhouse-grown plants have been successfully grown in field plots in western and south Florida during a 10-month research trial (Smith et al. 2014).

Literature Cited

Gilman, E.F. 2014. Licania michauxii Gopher Apple. FPS-342. Gainesville: University of Florida Institute of Food and Agricultural Sciences. https://edis.ifas.ufl.edu/fp342 (no longer available online).

Smith, A.M., S.B. Wilson, M. Thetford, K.L. Nolan, and C. Reinhardt Adams. 2014. "Performance of nine Florida native wildflower species grown in varying container substrates." Native Plants Journal 15(1):75–86. https://doi.org/10.3368/npj.15.1.75

Wilson, S.B., H. Perez, and M. Thetford. 2010. Propagation, Production, and Landscape Evaluation of Native Wildflowers in West, Central and South Florida. Condensed Progress Report for the Florida Wildflower Foundation. https://www.flawildflowers.org/wp-content/resources/pdfs/Research/Wildflower%20year-end%20progress%20report-Wilson%20et%20al.pdf

Hypericaceae

Atlantic St. John's wort occurs throughout Florida and more broadly west to Alabama and northeast to North Carolina on beach dunes and scrub plant communities frequently associated with wet depression areas. Hypericum is a large genus of plants with 31 species in Florida alone (Wunderlin et al. 2017). This plant is a prolific flower producer that attracts numerous pollinators

General Description

Atlantic St. John's wort is a semi-woody to herbaceous perennial subshrub with a decumbent growth habit; forming a small rounded shrub to a low mat that rarely reaches above 1.5 ft. Leaves are simple, opposite, and needlelike. Stems are often decumbent and matted and are 6-angled in cross-section when young. Flowers have 5 persistent sepals, 5 yellow petals, and bear numerous stamens. They are 0.4 to 01.8 in wide, are axillary and terminal, are solitary or grow in small clusters called cymules or dichasia, and flower from June to September. Fruits are capsules 6 to 10 mm long and turn brown when ripe.

Propagation

Atlantic St. John's wort can be propagated from stem cuttings. The following is adopted from Thetford and Miller (2004). Collect 4-in terminal stem cuttings during the growing season. Remove leaves of bottom ½ in of cutting and quick dip in auxin [NAA (1-Naphthaleneacetic acid) 500 to 1000 ppm, or IBA (Indole-3-butyric acid) 1000 to 5000 ppm, or Dip 'N Grow] for 1 second (Thetford and Miller 2002). Root cuttings in 72-cell flats with a well-drained substrate under intermittent mist and natural photoperiod. Roots initiate within 2 to 3 weeks. By week 4, rooted cuttings may be removed from mist, and by week 6, transplants can be moved into larger pots (4-in, 1-qt or 1-gal). Rooted cuttings benefit from fertigation with a complete fertilizer solution providing nitrogen at a rate of 150 ppm 1 to 2 times a week before transplanting to larger containers. An additional 4 to 6 weeks of outdoor production with supplemental irrigation is required to develop a full rootball.

No published information on germination requirements of Hypericum tenuifolium is available. Germination requirements for the related species, H. perforatum are variable across populations but need light to germinate with constant (15 and 25°C) or fluctuating (25/15°C) day/night temperatures and are non-dormant (Pérez-García et al. 2006). Light has been reported as necessary for germination of other Hypericum sp. with similar optimal germination temperatures, but physiological or physical dormancies have also been reported (Çirak et al. 2007; Çirak 2007.)

Outplanting

No published information on outplanting information is presently available for Atlantic St. John's wort. The authors have successfully transplanted this species in home landscape situations with minimal supplemental irrigation. In Florida, H. tenuifolium is considered a facultative wetland species (occurs in wetlands 67% to 99% in the wild) (Wunderlin et al. 2017) and in coastal communities this species is associated with coastal interdunal swales and adjacent low ridges.

Literature Cited

Campbell, M.H. 1985. "Germination, emergence and seedling growth of Hypericum perforatum L." Weed Research 25(4):259–266. https://doi.org/10.1111/j.1365-3180.1985.tb00643.x

Çirak C., K. Kevseroglu, and A.K. Ayan. 2007. "Break seed dormancy in a Turkish endemic Hypericum species: Hypericum aviculariifolium subsp. depilatum var. depilatum by light and some pre-soaking treatments." Journal of Arid Environments 68(1):159–164. https://doi.org/10.1016/j.jaridenv.2006.03.027

Çirak, C. 2007. "Seed germination protocols for Ex situ conservation of some Hypericum species from Turkey." American Journal of Plant Physiology 2(5):287–294. https://doi.org/10.3923/ajpp.2007.287.294

Pérez-García, F., M. Huertas, E. Mora, B. Peña, F. Varela, and M.E. González-Benito. 2006. "Hypericum perforatum L. seed germination: interpopulation variation and effect of light, temperature, presowing treatments and seed desiccation." Genetic Resources and Crop Evolution 53:1187–1198. https://doi.org/10.1007/s10722-005-2012-3

Thetford, M., and D.L. Miller. 2002. "Propagation of 4 Florida coastal dune species." Native Plants Journal 3(2):112–120.

Thetford, M., and D.L. Miller. 2004. Propagation and Production of Atlantic St. John's Wort. ENH972. Gainesville: University of Florida Institute of Food and Agricultural Sciences. https://doi.org/10.32473/edis-ep229-2004

Wunderlin, R.P., B.F. Hansen, A.R. Franck, and F.B. Essig. 2017. Atlas of Florida Plants. [S. M. Landry and K. N. Campbell (application development), USF Water Institute.] Institute for Systematic Botany, University of South Florida, Tampa. http://florida.plantatlas.usf.edu/

Aquifoliaceae

Inkberry is found throughout Florida and more broadly west to Texas and northeast to the Canadian border. Fruits attract birds and other wildlife but are not edible to humans. Flowers attract pollinators, including honey bees. Plant male and female plants in order to sustain fruit production.

General Description

Inkberry is a colonial, evergreen shrub that can reach heights of 3 to 6 ft. Leaves are alternate and simple, growing from 0.75 to 3 in long. They have dark green upper surfaces and powdery pubescent petioles. Leaf margins are entire or they may have up to 6 rounded serrations or notches toward the apices and the apices will have a tiny point. Inflorescences are borne in the leaf axils and appear in spring. They are clusters of white flowers that grow 5 to 8 mm in diameter. The species is dioecious with pistillate and staminate flowers occurring on separate plants. Fruits contain 5 to 8 nutlets. They are shiny black spherical drupes 5 to 8 mm in diameter. Fruits often persist through winter.

Propagation

The authors have had much success producing inkberry from seed of wild-collected fruits. Fruit can be harvested in January and cleaned seed sown in open flats or in 72-cell flats after moist, cool stratification (40 days at 4.5°C) to overcome seed dormancy associated with immature embryos. Germination may occur over an extended period; seedlings are grown for 4 months before they are transplanted to larger pots.

Outplanting

Plants grown in 3-gal treepots with ½-inch screened composted pinebark had 2 to 6 times greater outplanting survival and were 1.5 times larger after 15 months than plants grown in 1-gal pots (Thetford et al. 2005). Outplanting should be done with protection of a foredune ridge above a meter or at least 466 ft from the Gulf mean high tide line.

Literature Cited

Thetford, M., D. Miller, K. Smith, and M. Schneider. 2005. "Container size and planting zone influence on transplant survival and growth of two coastal plants." HortTechnology 15(3):554–549. https://doi.org/10.21273/HORTTECH.15.3.0554

Aquifoliaceae

Yaupon is found throughout Florida south to Lake Okeechobee and more broadly throughout the southeast west to Texas and east to North Carolina.

The leaves and small twigs of yaupon contain caffeine, and yaupon teas have been consumed by humans for centuries. The fruits and flowers of yaupon attract wildlife, especially birds and pollinators, and it is a larval host plant for Henry's elfin butterfly (Callophrys henrici) (Lotts and Naberhaus 2017). Yaupon is used in landscaping and can tolerate a wide range of environmental conditions. Several cultivars are available in the horticultural industry.

General Description

Yaupon is a dioecious evergreen shrub to small bushy tree that can reach heights of 25 ft. Leaves are alternate, simple, and dark green on the upper surface. They are elliptical to ovate, 0.2 to 2 in long by 0.2 to 0.5 in wide, and have a crenate margin, an obtuse apex, and a rounded base. Flowers are small and white and occur in leaf axils. The species is dioecious with pistillate and staminate flowers occurring on separate plants. Fruits are bright red spherical drupes that grow 5 to 7 mm wide and occur in fall and persist throughout the winter.

Propagation

The authors have had much success growing yaupon from seed of wild-collected fruits. Fruit harvested in winter months (January) are placed in water and pressed to clean flesh from seed. Cleaned seeds are sown in open flats or in 72-cell liners after moist, cool stratification (40 days at 4.5°C) to overcome seed dormancy associated with immature embryos. Germination may occur over an extended period; seedlings are grown for 2 to 4 months before they are transplanted to larger pots.

Yaupon is a common nursery crop, and vegetative propagation methods are numerous for yaupon cultivars. Generally, semihardwood (fall) cuttings can be treated with 3,000 ppm IBA (Indole-3-butyric acid) solution while hardwood (dormant winter cuttings) can be treated with 5,000 ppm IBA solution. Craig (1991) suggests using NAA (1-Naphthaleneacetic acid) on hardwood cuttings. Cuttings are rooted under intermittent mist in a well-drained substrate. Wild-collected cuttings should be collected from a broad range of plants to ensure a broad genetic diversity and a mixture of male and female plants.

Outplanting

Plants have higher outplanting survival in 14-in-deep tree pots (versus the standard 1-gal pots) and in interdunal swales (versus ridges) (Thetford et al. 2015). Outplant yaupon in the proximity of shallow swales for optimal transplant survival.

Literature Cited

Craig, R.M. 1991. "Plants for coastal dunes of the Gulf and south Atlantic coasts and Puerto Rico." USDA SCS. Agriculture Information Bulletin 460.

Lotts, K., and T. Naberhaus. 2017. Butterflies and Moths of North America. http://www.butterfliesandmoths.org/

Thetford, M, D.L. Miller, L.W. Atwood, and B.O. Ballard. 2015. "Microsite and rooting depth are more important than water-holding gel for establishment of restoration plantings of Ilex vomitoria on barrier islands in the Gulf of Mexico." Native Plants Journal 16(2):77–86. https://doi.org/10.3368/npj.16.2.77

Convolvulaceae

Two species of Ipomoea are found in coastal beach plant communities of the Florida Panhandle; beach morning-glory (Ipomoea imperati) and railroad vine (Ipomoea pes-caprae subsp. brasiliensis). Beach morning-glory and railroad vine are distinguished by the colors of their corollas and the shapes of their leaves. Beach morning-glory flowers are white with yellow and purple in the throat and leaves are elliptical and notched; whereas railroad vine has a pink to purple flower and kidney-shaped leaves. Beach morningglory flowers occur from spring to fall, while railroad vine flowers are present year-round.

Both plants occur throughout coastal Florida, however railroad vine has been documented in more counties. More broadly, these plants are found in coastal states west to Texas and northeast to North Carolina. Disjunct populations may exist in Pennsylvania as well.

Both species have been reported to occur there. These plants occur in beach dunes and are important sand stabilizers and colonizers after disturbances. The seeds are important forage for several types of wildlife, including endangered beach mice.

General Description

Both species are stoloniferous, scrambling, creeping perennial vines that reach extreme lengths, upward of 30 ft or more. Leaves are simple and alternately arranged, with or without lobes. They have elongated petioles. Stems are trailing, fleshy, and glabrous, forming roots at nodes. Inflorescences are solitary and axillary. Sepals are coriaceous, glabrous, or pubescent, and corollas are funnelform to campanulate (funnel to bell shaped) with 5 stamens and the style included in the corolla. Interestingly, railroad vine flowers only last one day. Fruits are dry, dehiscent capsules with 4 large seeds.

Propagation

The authors propagate beach morning-glory stem cuttings without the application of auxins. Single- or multiple-node stem cuttings can be taken along any portion of the stem. Place at least one node into the rooting substrate and place under intermittent mist with natural photoperiod until roots form. Cuttings root within 7 to 10 days and should be removed from mist at the first sign of rooting, or they will quickly deteriorate. Hand water until plants form sufficient roots to hold the propagation substrate when removed from the propagation cell.

Plants grow quickly once transferred to production containers with a well-draining substrate in either greenhouse or nursery conditions. Railroad vine can also be propagated from cuttings in a similar manner. Seeds of railroad vine are physically dormant and must be scarified in order to germinate (Devall and Thien 1989). In the wild, seeds germinate during all seasons except for winter (Devall 1992).

Germination for beach morningglory requires scarification because seeds are physically dormant (Martínez et al. 1992). Seeds germinate with both constant (90% at 35°C) and fluctuating day/night temperatures (60 to 85% at 40/20°C) in dark or light. Seeds retain germinability when buried up to 0.75 in and inundated with 25% seawater.

Outplanting

No published outplanting information is available. The authors have transplanted beach morning-glory in spring and early summer months with high success. Transplants may experience an initial foliar salt burn when transferred from the nursery to high salt and wind conditions. However, transplants will quickly regrow from existing stems or from the base of the plant because of the stoloniferous characteristics of the species.

 Literature Cited

Devall, M.S. 1992. "The biological flora of coastal dunes and wetlands 2. Ipomea pes-caprae (L.) Roth." Journal of Coastal Research 8(2)442–456.

Devall, M.S., and L.B. Thien. 1989. "Factors influencing the reproductive success of Ipomoea pes-caprae (Convolvulaceae) around the Gulf of Mexico." American Journal of Botany 76(12):1821–1831. https://doi.org/10.1002/j.1537-2197.1989.tb15171.x

Martínez, M.L., T. Valverder, and P. Moreno-Casasola. 1992. "Germination response to temperature, salinity, light and depth of sowing of ten tropical dune species." Oecologia 92:343–353. https://doi.org/10.1007/BF00317460

Asteraceae

Seacoast marshelder is an important plant for dune restoration, stabilization, and formation because of its ability to trap sand. It grows on foredunes and forms low, rounded dunes as sand accumulates (Craig 1991). As the aboveground portions of the plant become buried by sand, rooting is stimulated in stem tissue (Craig 1975). This gives the appearance that the plant is rhizomatous when in fact it is the sand burial resulting in the presence of below-ground stems. This plant occurs throughout coastal Florida (except for the Big Bend coast) and in coastal southeastern states west to Texas and northeast to Virginia.

General Description

Seacoast marshelder is a sparsely branched, succulent, shrub-like perennial herb that can reach heights of 1 to 4 ft and widths up to 6 ft. Leaves are without stalks, succulent, lance shaped, and mostly arranged oppositely (at the base of the plant) early in the season and become alternate (near the top of the plant) later in the season. Leaves are 0.75 to 2 in long with blades narrowing at tip and have almost entire margins. Inflorescences are non-showy terminal racemes that appear in late summer and continue to elongate through early fall with leaf-like bracts below initial flowers and smaller bracts below later flowers. Flowers have cream to white to greenish petals that are 1.5 mm long. Fruits are achenes, 3.5 to 5 mm long, brown to yellow, and globe shaped. Seeds are retained in the dried calyxes of the flowers throughout the winter months until the plants begin to break apart and the seeds are dispersed as the plant parts are blown by beach breezes.

Propagation

Cutting propagation of seacoast marshelder is possible with 2- and 4-in stem cuttings. Cuttings obtained from early season flushes of growth that are flexible but not stiff (softwood cuttings) root with greater than 70% success without auxin application. Short lateral stems may be used to prepare 2-in cuttings and a quick-dip in 1,000 ppm IBA (Indole-3-butyric acid) will improve rooting for these lateral cuttings (Thetford and Miller 2002). Additionally, the success of rooting (rooting percentage) and quality of shoot tip cuttings (root number and root length) are variable across seasons (Raymer et al. 2008).

The following cutting propagation protocol is adapted from Thetford and Miller (2004). Collect 4-in softwood cuttings from the tips of non-branched terminal shoots in early spring through summer. Cuttings should not be collected from floral portions of the stem because these portions of the stem have no lateral buds from which to initiate new vegetative shoots. Cuttings may be rooted in 72-cell flats under mist for 3 to 4 weeks followed by hand watering for another 2 to 3 weeks in a well-draining substrate such as a commercial potting mix or 100% milled pine bark. Rooted cuttings may be fertilized with a complete fertilizer using a rate of 150 ppm N solution applied 1 to 2 times a week. Plants can be pruned to stimulate branching starting week 4 or 5 or up to 1 week after transplanting to larger pots. Plants perform well in 4-in and 1-qt pots and require 4 to 6 weeks of additional growth to develop a full rootball and a canopy of 6–8 in.

Establishing productive nursery stock plants is possible for seacoast marshelder. The following is adapted from Raymer et al. (2008). Stock plants may be grown in 1-gal containers using a pine-bark substrate amended with 6 lb/yd3 dolomitic limestone with 11 gm (recommend rate) of a 15N–3.9P–10K controlled-release fertilizer. Stock plants started in the spring from dormant liners have the most productive cuttings when taken during May to early June and August while stock plants established from actively growing liners are most productive from September to November. Every effort should be made to increase plant width by pruning during early spring and summer and a cutting harvest should be planned from May to early June. July should be a period to allow for vegetative growth before any subsequent harvests.

Seeds from a North Carolina population had physiological dormancy that was alleviated with cold stratification for at least 30 days at 4C (Van Der Valk 1974). The stratified seed then needed to be germinated with daily alternating temperatures of 10/15 or 15/25°C, in light or dark, to achieve high germination percentages. Seeds can be collected and readily germinate in fall (Graetz 1973). Similarly, seeds collected by the authors in fall, placed in a plastic bag, and stored at ambient temperature for 3 months germinated readily under intermittent mist.

Outplanting

Plants should be planted well above the mean high tide line on Gulf-facing foredunes. Small, one-year-old transplants have been successfully transplanted in early spring (Graetz 1973). The authors have successfully transplanted plants produced in 4-inch pots using a pine-bark substrate at nearly 100% survival in foredune locations both alone and in conjunction with other foredune grasses (Stoddard et al. 2014).

Literature Cited

Craig, R.M. 1975. "Woody vegetation for coastal dune areas." Proceedings of the Florida State Horticultural Society 88:428–434.

Craig, R.M.1991. "Plants for coastal dunes of the Gulf and south Atlantic coasts and Puerto Rico." USDA SCS. Agriculture Information Bulletin, Issue no. 460.

Graetz, K.E. 1973. "Seaside plants of the Carolinas." USDA, SCS, and University of North Carolina Sea Grant Program. Sea Grant Publication.

Raymer, J., M. Thetford, and D.L. Miller. 2008. "Fertility rate of seacoast marshelder stock plants influences cutting production and rooting characteristics of stem cuttings." HortTechnology 18(3):372–378. https://doi.org/10.21273/HORTTECH.18.3.372

Stoddard, M., D.L. Miller, L.C. Branch, and M. Thetford. 2014. "Endangered beach mouse: Linking population studies/habitat restoration to predict sea level rise." Final Report submitted to Gulf Islands National Seashore, Gulf Coast Cooperative Ecosystems Studies Unit Project H5000 02 A271. 130 p.

Thetford, M., and D.L. Miller. 2004. Propagation and Production of Seacoast Marshelder. ENH-975. Gainesville: University of Florida Institute of Food and Agricultural Sciences. https://doi.org/10.32473/edis-ep232-2004

Thetford, M., and D.L. Miller. 2002. "Propagation of four Florida coastal dune species." Native Plants Journal 3(2):112–120.

Van Der Valk, A.G. 1974. "Environmental factors controlling the distribution of forbs on coastal foredunes in Cape Hatteras, National Seashore." Canadian Journal of Botany 52:1057–1073. https://doi.org/10.1139/b74-135

Fabaceae

Gulf coast lupine (Lupinus westianus var. westianus) is listed as threatened by the Plants in the Preservation of Native Flora of Florida Act, Chapter 5B-40, Florida Administrative Code, 1998, amended (Wunderlin et al. 2017). The species is endemic to coastal counties in the western Panhandle of Florida. Two disjunct populations are noted with Lupinus westianus var. aridorum occurring only in the central peninsula of Florida. Gulf coast lupine occurs in beach dunes, coastal grasslands, coastal scrub, sandhills, and disturbed areas such as roadsides. Gulf coast lupine can be distinguished from a similar lupine (L. diffusus) by the lack of a petiole. Several pollinators are sustained by gulf coast lupine, and the inflorescences are remarkably showy. Lupines form symbiotic relationships with nitrogen-fixing microorganisms within the soil (Gutiérrez Mañero et al. 2003).

General Description

Gulf coast lupine is a shrubby biennial or short lived perennial herb that grows up to 3 ft tall. It is most commonly found on exposed and active sand dunes and on sandy disturbed areas. Leaves are alternately arranged and superficially appear simple but are in fact a compound leaf with only one leaflet (unifoliate). Stems are herbaceous when young but become woody with age. Inflorescences are terminal spikes that occur in the spring. Flowers have purple to blue corollas with red to purple spots on the standard, are densely arranged on the stalk, and resemble the flowers of peas. Fruits are hairy legumes.

Propagation

No published propagation information is available for gulf coast lupine. However seed germination of related lupine species has been studied. Lupine seeds exhibit physical dormancy and need to be scarified in order to germinate. Seeds of sky blue lupine (Lupinus diffusus), a related scrub species, achieved 70% germination following 20 seconds scarification in an electric seed scarifier (Forsbergs, Inc.) after one year in dry storage at room temperature (Campbell 2016). The authors were able to germinate sky blue lupine seed and grew seedlings in a climate-controlled greenhouse to a 3-inch height before all seedlings became chlorotic and died. We speculate the plants lacked the soil mycorrhiza in the production substrate and were unable to form symbiotic relationships with the nitrogen-fixing microorganisms required for their survival.

Outplanting

No published outplanting information exists for gulf coast lupine. Other species of lupine have specific mycorrhizal associations and are notorious for poor survival rates during transplantation.

Literature Cited

Campbell, G. 2016. "Dormancy and germination characteristics of two Florida native forbs, Asclepias humistrata and Lupinus diffusus." Masters thesis. University of Florida.

Gutiérrez Mañero, F.J., A. Probanza, B. Ramos, J.J. Colón Flores, and J.A. Lucas García. 2003. "Effects of culture filtrates of rhizobacteria isolated from wild lupine on germination, growth, and biological nitrogen fixation of lupine seedlings." Journal of Plant Nutrition 26(5):1101–1115. https://doi.org/10.1081/PLN-120020078

Wunderlin, R.P., B.F. Hansen, A.R. Franck, and F. B. Essig. 2017. Atlas of Florida Plants. [S. M. Landry and K. N. Campbell (application development), USF Water Institute.] Institute for Systematic Botany, University of South Florida, Tampa. http://florida.plantatlas.usf.edu/

Myricaceae

Wax myrtle is one the most widespread plants in Florida, and it is found in coastal states west to Texas and north to New Jersey. The wax found around seeds can be melted down to make candles. The fruits of wax myrtle are important for birds and other wildlife, and the plant is a larval host for the banded hairstreak and redbanded hairstreak butterflies (Satyrium calanus and Calycopis cecrops, respectively) (Lotts and Naberhaus 2017). Wax myrtle has been shown to contribute substantial nitrogen addition to soils via symbiotic relationships with nitrogen-fixing microorganisms residing in soils (Permar and Fisher 1983).

General Description

Wax myrtle is an evergreen shrub to small tree with several trunks that can reach heights of 40 ft. Leaves are alternate, simple, narrowly oblanceolate, 2 to 6 in long by 0.4 to 0.8 in wide, aromatic, and dense, with a toothed margin toward the apex and surfaces covered in amber dots. It may require magnification to see the dots clearly. Inflorescences are catkins, male or female, axillary, 0.8 in long, numerous, and occur in early spring. The species is dioecious with pistillate and staminate flowers occurring on separate plants. Fruits are rounded, blue, wax-coated drupes 2 to 4 mm in diameter.

Propagation

Southern nurseries usually produce wax myrtle from seed or cuttings. It is commonly used as a landscape plant. To propagate cuttings from plants existing on restoration sites, collect softwood cuttings and treat with moderate rates of IBA (Indole-3-butyric acid) at 5,000 to 8,000 ppm or mixtures such as 1,000 ppm IBA and 500 ppm NAA (1-Naphthaleneacetic acid). Root cuttings under intermittent mist; they will show root growth at approximately 4 weeks.

Seed germination requires removal of the wax coating from the fruit. Wash the fruit in warm detergent water and rinse with plain cool water. Seed require a cool, moist stratification period of 40 to 90 days. Seeds can be sown in open flats and covered with ¼ in of vermiculite. Stratification is necessary to overcome physiological dormancy; hence seed from more northern populations may have a longer stratification requirement than southern populations (Krochmal 1974).

Outplanting

The authors have successfully transplanted wax myrtle grown in 1-gal containers to Santa Rosa Island with a survival of 50 to 65% 15 months after planting, when plants were located a minimum of 560 ft from the gulf (Miller, Thetford, and Schneider 2008). Morella was not tolerant of the levels of salt spray when planted closer to the Gulf or when planted behind dunes less than 3.3 to 6.6 ft high. Transplants experienced significant foliar loss and twig death at 660 ft from the gulf when protective dunes were less than 6.6 ft high. Surviving plants exhibited regrowth from the basal portions of the plants, and we concluded that these plants would need additional dune development or should be planted further back from the Gulf within the dune field or located in close proximity to swales.

Plants grown from rooted cuttings in 60-cell flats have been successfully outplanted within the low dune field on barrier islands in the Panhandle of Florida (Lumban Tobing 2009). Plants should be placed at low spots of interdunal swales during the spring and should be initially irrigated if drought conditions are present.

Literature Cited

Krochmal, A. 1974. "Myrica L. Bayberry." In: Schopmeyer, C. S., ed. Seeds of woody plants in the United States. Agriculture Handbook no. 450. Washington: U. S. Department of Agriculture, Forest Service. pp. 548-550.

Lotts, Kelly, and Thomas Naberhaus, coordinators. 2017. Butterflies and Moths of North America. http://www.butterfliesandmoths.org/

Lumban Tobing, S.T. 2009. "Germination and establishment of woody species with barrier island interdunal swales." Master's thesis. University of Florida.

Miller, D.L., M. Thetford, and M. Schneider. 2008. "Distance from the Gulf influences survival and growth of three barrier island dune plants." Journal of Coastal Research 24(3):261–266. https://doi.org/10.2112/07-0914.1

Permar, T.A., and R.F. Fisher. 1983. "Nitrogen fixation and accretion by wax myrtle (Myrica cerifera) in slash pine (Pinus elliottii) plantations." Forest Ecology and Management 5(1):39–46. https://doi.org/10.1016/0378-1127(83)90067-1

Onagraceae

Seabeach evening primrose is found in beach dunes throughout coastal counties in Florida, west to Louisiana, and as far north as New Jersey.

General Description

Seabeach evening primrose is an herbaceous perennial with horizontal stems forming a rounded, mounding canopy. Leaves are simple and alternate and wider than 1 mm with short, silky pubescence. Stems are prostrate, grow up to 3 ft long, and are covered with silky appressed pubescence. Flowers are axillary with 4 yellow petals that are 0.2 to 0.6 in long, 4 sepals that are 0.1 to 0.4 in long, and flattened bracts. They have a hypanthium that is longer than the ovary. Fruits are 10- to 35-mm-long dehiscent capsules with appressed hairs that give rise to numerous rounded seeds.

Propagation

No published seed propagation information is presently available for O. humifusa; however, other Oenothera species are well studied and have been shown to require light to germinate (Greiner and Köhl 2014). The authors collected stem cuttings in the fall and found the seeds present within the capsules already on the cuttings readily germinated in propagation flats under intermittent mist and natural photoperiod post-dehiscence. Seedlings initially form a low, broad rosette and are easily transplanted as small plugs after two weeks' growth in the propagation flat. Seedling growth is eventually lateral becoming multibranched. Seedlings will fill 4-in pots in 4 weeks when grown outdoors with overhead irrigation and fertilized with slow-release fertilizer.

The authors found stem cuttings of Oenothera rapidly and readily produce roots without auxin application. Apical stem cuttings taken in late April 2017 from Santa Rosa Island, Florida, rooted and filled 162-cell flats in less than 4 weeks while under intermittent mist and natural photoperiod in a controlled-environment greenhouse. Cuttings grown in 72-cell flats filled 4-in pots in 4 weeks when grown outdoors under overhead irrigation and fertilized with slow-release fertilizer.

In nursery culture, this plant may become infested with flea beetles (Altica sp). The preferred plant hosts of this insect are likely limited to the members of the evening primrose family, Onagraceae (Clark et al. 2004). The beetle is a problem on Oenothera in the spring (May–June in north Florida) when larvae and adults appear in large numbers and can feed on the host plant until it dies. The authors have not noted this insect to be a serious pest of Oenothera growing within coastal plant communities, likely related to the harsh environment and presence of natural enemies. Commercial pest management recommendations are available to manage the pest in nursery culture.

Outplanting

Plants in 4-in pots with fully developed rootballs and canopies have successfully been outplanted by the authors. In a preliminary trial, when planted in July on open beach areas behind low frontal dunes, transplant success was 43%. However, in subsequent plantings in early March survival was 100% after 2 months. Plants were outplanted on backdunes midslope at least 12 in from each other and existing perennial grasses. Fertilizer application (½ tsp Osmocote 18-6-12) improved the aesthetic appearance of plants and increased biomass for this plant but was not necessary for survival.

Literature Cited

Clark, S.M., D.G. LeDoux, T.N. Seeno, E.G. Riley, A.J. Gilbert, and J.M. Sullivan. 2004. "Host plants of leaf beetle species occurring in the United States and Canada (Coleoptera: Megalopodidae, Orsodacnidae, Chrysomelidae exclusive of Bruchinae)." Coleopterists Society, Special Publication no. 2. 476 pp. https://doi.org/10.5962/t.208370

Greiner, S., and K. Köhl. 2014. "Growing evening primrose (Oenothera)." Frontiers in Plant Science 5(38):1–12. https://doi.org/10.3389/fpls.2014.00038

Poaceae

Bitter panicgrass is important in dune stabilization and building and often grows intermixed with sea oats on foredunes. It is also found spread throughout back dunes, interdunal swales, and coastal grasslands. This plant occurs throughout coastal Florida, except for the Big Bend coast, west to New Mexico, and along coastal northeast states to Massachusetts. A significant proportion of bitter panicgrass reproduction is by vegetative spread; its seeds are often sterile.

General Description

Bitter panicgrass is a bluish green, rhizomatous, perennial, clumping grass that can reach heights of 3.3 ft or more. Aboveground stems (culms) are thick, branch from lower nodes, can be upright or horizontal, and have glabrous (smooth) nodes and grey glabrous to glaucous (waxy) internodes. Leaves are up to 20 in long and 0.75 in wide, and have flat bases and smooth and involuted tips. The sheaths are glabrous with hairy upper margins. The ligules are membranous, up to 0.33 in long, and ciliate. Inflorescences are elongated panicles, up to 20 in long. They occur in late spring to late summer. Panicles are narrow, slightly nodding, and densely flowered. Flowers are typical grass spikelets, somewhat purple/gray, 0.33 in long, glabrous, and ovoid with lower glumes that reach half the spikelet length and are 3- to 9-veined. Fruits are smooth, shiny achenes and are also purple/gray.

Propagation

Above- and below-ground portions of bitter panicgrass can produce new plants (Willis and Hester 2008). Culms with at least 2 nodes can be placed vertically in a pot with well-draining propagation medium (USDA NRCS 2017). Seedlings from a wild Louisiana population were successfully transplanted to a greenhouse and grown in 2L (0.53 g) pots with 1.6-mm sieved and sterilized sand collected at the growing site (Hester and Mendelssohn 1990). These same plants did not respond to micronutrient application but did respond positively to macronutrient fertilizer application one week after transplanting. Additionally, humic acid (80g/mL) has been used to increase biomass for container-grown bitter panicgrass (Willis and Hester 2008).

The authors collected elongated culms and dissected them into single-node cuttings. These cuttings were placed in a coarse propagation substrate containing milled pine bark. The cuttings were inserted vertically to a depth that placed the visible bud at the node even with the substrate surface. Cuttings placed under intermittent mist produce roots within a few days. Once roots are evident, the rooted cuttings should be placed on greenhouse benches to grow until new shoots are a few inches tall. Well-rooted liners can be transplanted to 4-in pots and outplanted within 4 to 6 weeks when rootballs are sufficiently dense to hold the substrate together when the plant is removed from the pot. Timing will depend on root growth rates.

The potential for collection of nonviable seed is high and likely to be an important factor in producing these plants from seed. Seed viability varies considerably across populations and year collected (Senaca 1969).

Outplanting

Miller et al. (2001) reported increased growth (more tillers and more branching) for bitter panicgrass when it was planted in March than when it was planted in December. Bitter panicgrass can be transplanted during the summer, but summer planting is not recommended unless supplemental water is available or rainfall is consistent (i.e., rainfall levels are average or above average). Planting without supplemental water in May, the lowest rainfall month is not recommended unless supplemental water is available or rainfall is consistent.

Literature Cited

Hester, M.W., and I.A. Mendelssohn. 1990. "Effects of macronutrient and micronutrient additions on photosynthesis, growth parameters, and leaf nutrient concentrations of Uniola paniculata and Panicum amarum." Botanical Gazette 151(1):21–29. https://doi.org/10.1086/337800

Lamphere, J. 2017. "Plant guide – bitter panicum." USDA NRCS Golden Meadow Plant Materials Center. United States Department of Agriculture (USDA) Natural Resource Conservation Service (NRCS). The PLANTS Database. http://plants.usda.gov/plantguide/pdf/pg_paam2.pdf

Seneca, E.D. 1969. "Germination response to temperature and salinity of four dune grasses from the outer banks of North Carolina." Ecology 50(1):45–53. https://doi.org/10.2307/1934661

Willis, J.M., and M.W. Hester. 2008. "Evaluation of enhanced Panicum amarum establishment through fragment plantings and humic acid treatment." Journal of Coastal Research 24(2B):263–268. https://doi.org/10.2112/06-0669.1

Miller, D.L., M. Thetford, and L. Yager. 2001. "Evaluation of sand fence and vegetation for dune building following overwash by Hurricane Opal on Santa Rosa Island, Florida." Journal of Coastal Research 17(4):936–948.

Caryophyllaceae

Squareflower is found in beach dunes, coastal grasslands, and scrub. This plant is an endemic restricted to the coastal Panhandle of Florida, counties west of the Big Bend region, and west to Louisiana. The square outline of the inflorescence is unique and makes squareflower a desirable plant for coastal landscapes.

General Description

Squareflower is a multiple stemmed, herbaceous perennial species with a short canopy. Leaves are purple to pink to green, opposite, and up to 3 mm wide with linear to oblong papery stipules that are ½ to ¼ as long as the leaves. Stems are stout and round and curve upward. Inflorescences are multibranched corymbs branching with distinct regularity, which results in a characteristic branch pattern making the outline a square. Flowers are perfect, 2.5 to 3 mm long, and hypogynous, with 5 white sepals and no petals. They occur from March to November. Fruits are a single-seeded indehiscent utricle (achene).

Propagation

Auxin is not needed to initiate roots for stem cuttings of squareflower. The authors found wild collected apical stem cuttings (with or without floral buds) collected from late winter to late spring/early summer root readily within 2 weeks under intermittent mist. Adventitious roots produced by cuttings are very fibrous (small in diameter) and delicate, and much care was required when removing rooted cuttings from the propagation flats for transplanting to production containers. Plugs may require additional production time to allow sufficient root system formation and improvement of adventitious root connections to the cutting.

No published seed germination information is available for squareflower.

The authors found seeds collected in November and stored in the dark for 3 months in a greenhouse germinated readily within 2 weeks when placed on top of potting soil under intermittent mist with natural photoperiod in mid-February. A closely related species found in scrub (Paronychia chartacea subsp. chartacea) has been shown to not have seed dormancy (Stephens et al. 2012) but may require microorganisms (algae, lichens, cyanobacteria, mosses, fungi, and bacteria) within soil crusts to aid germination in the wild (Hawkes 2004).

Outplanting

Production information for this species has only recently been refined; hence, the authors have had limited experience transplanting square flower to the coastal dunes. Square flower has been successfully transplanted in informal plantings when grown in 4-in pots within protected beach dune areas behind a primary dune ridge. No survival data were obtained, and further experience and information are needed to make an informed recommendation.

Literature Cited

Hawkes, C.V. 2004. "Effects of biological soil crusts on seed germination of four endangered herbs in a xeric Florida shrubland during drought." Plant Ecology 170:121–134. https://doi.org/10.1023/B:VEGE.0000019035.56245.91

Stephens, E.L., L. Castro-Morales, and P.F. Quintana-Ascencio. 2012. "Post-dispersal seed predation, germination, and seedling survival of five rare Florida scrub species in intact and degraded habitats." American Midland Naturalist 167:223–239. https://doi.org/10.1674/0003-0031-167.2.223

Solanaceae

Coastal groundcherry occurs on beach dunes, coastal grasslands, coastal scrub, and disturbed areas. This plant is found throughout coastal counties on the west coast of Florida—except for the Big Bend region and the extreme southeasternmost counties—and more broadly west to Louisiana. Threatened and endangered beach mice and many other animals rely on this plant as a food source. Plants can be longed-lived and form relatively thick tuberous roots. Coastal groundcherry can hybridize with other Physalis species, particularly with P. viscosa, and has long frustrated plant taxonomists because of the inherent variation within the genus (Sullivan 1985).

General Description

Coastal groundcherry is an herbaceous perennial that forms thickened tuberous roots and stolons to spread asexually belowground, creating a sparse groundcover. Leaves are simple, alternate, linear, usually longer than 7 cm, mostly 8 times longer than wide, and glabrous. Inflorescences are solitary, axillary and bell- to wheel-shaped with a yellow corolla, occurring most months in frost-free areas. Fruits are yellow to orange edible berries that resemble a miniature tomatillo, being surrounded by a papery husk that looks like a tiny lantern.

Propagation

Stem cutting propagation of coastal ground cherry is readily accomplished from 4- to 6-in cuttings. Plants do not require auxin application to initiate roots, though auxin may decrease the time to rooting and improve rooting uniformity. Cuttings are placed under intermittent mist with root formation occurring within 2 weeks. Rooted cuttings should be removed from mist at the first sign of rooting, or they will quickly deteriorate and express signs of foliar oedema. Hand water until plants form sufficient roots to hold the propagation substrate when they are removed from the propagation cell.

Propagation of coastal groundcherry from seed is also easily accomplished. Sow seeds on the surface of a standard greenhouse media, keep them moist, and expose them to a natural photoperiod. The authors found dry, cleaned seed stored at room temperature in glass jars retain viability for at least 5 years.

Van der Valk (1974) studied seed germination of a closely related species, Physalis walteri (Walter's groundcherry). Seeds were determined to need light to germinate at constant temperatures. Seeds can be germinated in dark only if they are exposed to alternating day/night temperatures (15/25 and 20/30°C). Germination was near 100%. Seeds can tolerate burial up to 2 cm.

Outplanting

Plants in 4-in pots with fully developed rootballs and canopies have successfully been outplanted by the authors. In a preliminary trial, when planted in July on open beach areas behind low frontal dunes, transplant success was 55%.

Plants grown in 4-in pots and in 72-cell flats with well-developed rootballs and canopies have been outplanted successfully by the authors in early February with greater than 75% survival after 3 months, though plants from 4-in pots had higher survival and were far more robust. Plants were outplanted on the backdunes at midslope at least 12 in from each other and from perennial grasses. Fertilizer application (½ tsp Osmocote 18-6-12) improved the aesthetic and increased biomass for this plant but was not necessary for survival.

Literature Cited

Sullivan, J.R. 1985. "Systematics of the Physalis viscoa complex (Solanaceae)." Systematic Botany 10(4):426–444. https://doi.org/10.2307/2419136

Van Der Valk, A.G. 1974. "Environmental factors controlling the distribution of forbs on coastal foredunes in Cape Hatteras, National Seashore." Canadian Journal of Botany 52:1057–1073. https://doi.org/10.1139/b74-135

Polygonaceae

October flower is widespread throughout Florida and more broadly in coastal states west to Texas and northeast to Virginia. October flower is found in dune and scrub plant communities and ruderal areas. The showy flowers and attractive foliage make this native plant a desirable ornamental for landscapes.

General Description

October flower is an herbaceous short-lived perennial that can reach heights of 3 ft. Leaves are simple, alternate, linear, stipulate, 0.5 to 5 mm wide and persistent when fruit are present with veins that appear parallel and with inconspicuous secondary venation. Stipules are fused together around the stem in an entire ocrea. Branches are partly fused to the stem as if arising between the nodes. Inflorescences are prolific; racemes occur from July to October. Flowers are white to pink and contain male and female parts. They lack a corolla, have superior ovaries, and are subtended by a bract and two bracteoles. Fruit is an 0.8- to 1-mm-wide achene.

Propagation

Germination requirements of October flower are known (Heather 2009; Heather 2010). Seeds have non-deep physiological dormancy that is alleviated by warm or cold, moist stratification, application of 1,000 ppm GA (Gibberellic acid), or time in storage. Seeds prefer cooler temperatures (22/11°C) to warmer ones. Seeds collected between November and February have been successfully germinated.

Stem cutting production is possible on summer softwood stem cuttings of October flower (Heather 2009; Thetford et al. 2012). Application of auxin, such as IBA (Indole-3-butyric acid) is not needed for root initiation but may improve rooting performance. Greenhouse-grown plants perform well in both peat- and bark-based propagation media (Smith et al. 2014).

Outplanting

Greenhouse-grown plants of October flower performed well in a trial garden as a native wildflower producer for several months, with peak flowering in October (Smith et al. 2014). Beach dune outplanting information is not presently available.

Literature Cited

Heather, A.E. 2009. "A study on propagation methods for two native wildflowers: Polygonella polygama and Polygonella robusta." Master's thesis. University of Florida.

Heather, A.E. 2010. "Non-deep physiological dormancy in seeds of two Polygonella species with horticultural potential." HortScience 45(12):1854–1858. https://doi.org/10.21273/HORTSCI.45.12.1854

Smith, A.M., S.B. Wilson, M. Thetford, K.L. Nolan, and C. Reinhardt Adams. 2014. "Performance of nine Florida native wildflower species grown in varying container substrates." Native Plants Journal 15(1):75–86. https://doi.org/10.3368/npj.15.1.75

Thetford, M., A.E. O'Donoughue, S.B. Wilson, and H.E. Pérez. 2012. "Softwood cutting propagation of three Polygonella wildflower species native to Florida." Propagation of Ornamental Plants 12(1): 58–62.

Fagaceae

Sand live oak is found throughout northern Florida, more broadly west to Louisiana, and northeast to North Carolina. It is found in beach dunes, backdunes, sandhills, coastal areas, and inland areas with deep sandy soils. While this plant forms trees farther inland, it is commonly reduced to shrubs and sub-shrubs because of the extreme environmental conditions of the coast. The acorns of this plant are a valuable food source for wildlife. Sand live oak is available also in commercial nurseries and is often used as a landscape plant.

General Description

Sand live oak is within the white oak group and may be present as a shrub or tree with thick, roughly ridged, furrowed bark. The white oak group (synonym sect. Lepidobalanus or Leucobalanus) produce acorns that mature in 6 months (current season growth) and are frequently described as sweet or slightly bitter. Leaves are alternate, simple, thick, coriaceous, coarsely veined and 0.75 to 5 in long by 0.25 to 1.5 in wide. Upper leaf surfaces are dark green and glabrous, lower surfaces are dull gray to white and pubescent, and petioles are densely pubescent. Leaf margins are revolute, and the leaf blade is cupped, which gives it the shape of a boat. Inflorescences are catkins that appear in spring. Fruits are acorns, 0.4 to 0.8 in long and pointed; borne in a tapering cup that is about 0.3 in deep and has imbricate scales.

Propagation

Cutting propagation of sand live oak is not a practical approach for oak restoration because it would limit genetic diversity. Propagation from seed is accomplished easily. Acorns of Q. geminata are viviparous. The radical of the embryo does not stop growing necessitating immediate planting following seed harvest. Select acorns that are brown as yellowish acorns are generally not mature. Mature acorns will easily separate from the acorn cup. Collect acorns from branches rather than from the ground to minimize the collection of seeds containing weevil larvae. Perform a standard float test (discard those that float in water) to help eliminate acorns with underdeveloped seed and many impacted by weevils.

Acorns can be planted on the surface of a well-drained production substrate or the acorns may be covered lightly to a depth equal to the acorn diameter. Shoot emergence follows initial root system development.

Outplanting

Protect seeds planted in the wild from herbivores and high salinities. Bury them in the soil at a depth approximately the diameter of the acorn (Lumban Tobing 2009). Polyacrylamide gel is not recommended for outplanting of nursery-grown transplants from containers (Miller et al. 2013). The authors suggest outplanting in association with depressions to mimic natural dune-building processes that occur with sand accretion, to reduce initial drought stress, and to use explants with a deep root volume.

Literature Cited

Griffin, J., and N. Bassuk. 1996. Preliminary progress on the asexual propagation of oaks. Combined Proceedings, International Plant Propagators' Society 46:487–494.

Lumban Tobing, S.T. 2009. "Germination and establishment of woody species with barrier island interdunal swales." Master's thesis. University of Florida.

Miller, D.L., M. Thetford, and L.W. Atwood. 2013. "Effect of polyacrylamide gel on woody plant establishment in barrier island swales." Natural Areas Journal 33(4):500–508. https://doi.org/10.3375/043.033.0402

Fagaceae

Myrtle oak is one of the three scrub oaks characteristic of scrub communities. It occurs on coastal regions of the Florida Panhandle and throughout the Florida peninsula and coastal southeastern United States west to Mississippi and east to South Carolina. The acorns of myrtle oak are an important food source for wildlife.

General Description

Myrtle oak is within the red oak group and may be present as a shrub or tree. The red oak group (synonym sect. Erythrobalanus) produces acorns that mature in 18 months (generally on the previous season's growth at maturity) and are frequently described as very bitter. Myrtle oak is an evergreen shrub to small tree that can reach heights of 40 ft. Leaves are simple, alternate 0.8 to 3 in long by 0.4 to 2 in wide, variably shaped (elliptic, oblong, or oval), with margins entire to lobed and revolute, dark green upper surfaces and dull to yellowish green lower surfaces. When mature, leaves lack pubescence. Inflorescences are catkins that appear in spring. Fruits are globose acorns; the insides of the acorn shells are woolly.

Propagation

The authors have successfully germinated this plant in tree tubes within a climate-controlled greenhouse. After a late fall collection of acorns, plants were grown in a medium of 3 parts pine bark to 1 part horticulture media growing mix. Only collect acorns in late fall while still attached to the plant and without holes to avoid collecting seeds with weevil larvae inside. Perform a float test, discarding any acorns that float in water, to eliminate acorns with underdeveloped seed and many impacted by weevils.

No cutting propagation procedures for this species have been published. Additionally, cutting propagation is not considered a practical approach for oak restoration because it would limit genetic diversity. Other species of oak have been propagated from stem cuttings with various success and requirements (Griffin and Bassuk 1996).

Outplanting

Protect seeds planted in the wild from herbivores and high salinities, and bury them in the soil at a depth approximately the diameter of the acorn (Lumban Tobing 2009). The authors suggest outplanting in depressions to mimic natural dune-building processes that occur with sand accretion and to reduce initial drought stress.

Literature Cited

Griffin, J., and N. Bassuk. 1996. Preliminary progress on the asexual propagation of oaks. Combined Proceedings, International Plant Propagators' Society 46:487-494.

Lumban Tobing, S.T. 2009. "Germination and establishment of woody species with barrier island interdunal swales." Master's thesis. University of Florida.

Poaceae

Gulf bluestem occurs throughout the Florida Panhandle and in neighboring coastal states. Gulf bluestem helps stabilize dunes, forms thick stands in areas leeward of slopes (Craig 1991), replaces sea oats as the dominant species on protected foredunes behind a seaward ridge after 2 to 17 years (Johnson 1997), and occurs throughout flatwoods and disturbed areas. This plant is very closely related to little bluestem (Schizachyrium scoparium), and its taxonomic position is not entirely agreed upon by taxonomists; hence information may also be located using the taxonomic synonym Schizachyrium scoparium var. scoparium.

General Description

Gulf bluestem is a rhizomatous perennial grass with numerous crowded culms that reach heights of 1.5 ft. Leaves are clasping, sheathing, and flat at the base. They are up to 0.4 in wide and 6 in or more long, green or glaucous (chalky gray) with a bronze purple tinge. Ligules are 0.5 to 1 mm long. Culms are erect and, with age, the elongated culms become prostrate. Inflorescences are axillary and terminal, solitary racemes, with an inconspicuous rachis. Flowers are paired spikelets: a scabrous, 11-mm-long, sessile fertile spikelet, and a pedicellate, sterile or staminate, 10-mm-long spikelet. Fruits are caryopses.

Propagation

Cutting propagation protocols are described by Thetford and Miller (2002, 2004). Collect cuttings from basal portions of elongated culms during the growing season. If plant material is limited, cuttings can be taken from material above the basal 4 in of shoots, but these cuttings will need auxin (1,000 ppm IBA (Indole-3-butyric acid)) applications and will have only limited success. Collection of cutting material from older portions of the culms is necessary to ensure mature nodes are present on the cutting material.

Place cuttings in 72-cell flats with a well-drained substrate under intermittent mist for 3 to 4 weeks under natural photoperiod. Remove rooted cuttings from mist and hand water as needed for an additional 1 or 2 weeks. Fertigate 1 to 2 times a week with 150 ppm N fertilizer. On week 5 or 6 transplant to 4-in or 1-gal pots. Continue with container production for an addition 4 to 6 weeks to achieve a full rootball and a canopy of 6–8 in.

Propagation by seed is possible, but no published studies quantify optimal germination conditions or viability percentages. The authors have germinated field-collected seed in community flats with great success. However, it is noted that seeds appear to have an after-ripening requirement, because initial germination does not occur under standard greenhouse germination conditions until 35 to 40 days after sowing. Gulf bluestem plants readily seed in nursery ground beds and in neighboring pots in outdoor research production areas in Milton, Florida.

Outplanting

Gulf bluestem restoration planting should take place in the summer months, particularly June (Miller et al. 2008; 2014). Plants should be placed no closer than 130 ft (328 ft is the recommended distance) inland from the mean high tide line of the Gulf of Mexico from the foredunes into the coastal grassland and backdunes. Planting efforts in spring or fall have proven to result in high plant mortality because of sand loss and root exposure around transplants (Miller et al. 2014). Widely spaced transplants also are vulnerable to increased sand loss; therefore transplants should be no more than 12 in apart. Transplants are not detrimentally affected by sand burial but are susceptible to decreased survival from competition with other dune plants, particularly sea oats. Plants should be placed in areas with reduced wind exposure, such as areas with intact dunes, recovering dunes, or where the distance between barrier islands and mainland is reduced (Miller et al. 2008). Plantings with large contiguous areas will reduce the edge effect, which is deleterious for transplant survival in this species.

Literature Cited

Craig, R.M.1991. "Plants for coastal dunes of the gulf and south Atlantic coasts and Puerto Rico." USDA SCS. Agriculture Information Bulletin 460.

Johnson, A.F. 1997. "Rates of vegetation succession on a coastal dune system in northwest Florida." Journal of Coastal Research 13(2):373–384.

Miller, D.L., M. Thetford, and M. Schneider. 2008. "Distance from the Gulf Influences Survival and Growth of Three Barrier Island Dune Plants." Journal of Coastal Research 24(4A):261–266. https://doi.org/10.2112/07-0914.1

Miller, D.L., M. Thetford, J. Dupree, and L. Atwood. 2014. "Influence of seasonal changes and shifting substrate on survival of restoration plantings of Schizachyrium maritimum (Gulf bluestem) on Santa Rosa Island, Florida." Journal of Coastal Research 30(2):237–247. https://doi.org/10.2112/JCOASTRES-D-13-00031.1

Thetford, M., and D. Miller. 2002. "Propagation of four Florida coastal dune species." Native Plants Journal 3(2):112–120.

Thetford, M., and D. Miller. 2004. Propagation and Production of Gulf Bluestem. ENH-974. Gainesville: University of Florida Institute of Food and Agricultural Sciences. https://doi.org/10.32473/edis-ep231-2004

Asteraceae

Seaside goldenrod is highly tolerant of both saline soils and salt spray and is usually found on beach dunes, tidal marshes, and disturbed areas throughout coastal areas from Mexico North to Maine and on islands in the Bahamas. It is a prolific flower- and seed-producer. It attracts many pollinators, including birds, native bees, honey bees, butterflies (especially Monarch butterflies), and beneficial insects. The flowers are an important food/energy source for fall migrating monarch butterflies traveling the Atlantic coastal flyway (Sheahan 2014).

General Description

Seaside goldenrod is a perennial, herbaceous, clump-forming, stoloniferous species with high salt- and drought-tolerance. The plant may achieve heights of 1.3 to 6.6 ft and clumps may spread to widths of 1.6 ft.

Leaves initially in rosettes up to 40 centimeters long, glabrous, linear, entire, with cauline leaves that gradually reduce upward, appressed to the stem, and somewhat fleshy. Inflorescences are yellow heads in terminal panicles occuring from summer to fall. Panicles may be bent backwards and are arranged on one side. Yellow ray flowers are up to 5 mm long. Fruits are hairy achenes up to 2 mm long ripening in late summer to fall.

Propagation

Seeds from a North Carolina population, needed cold stratification and light to achieve high germination in constant 15 or 25°C or alternating day/night temperatures of 10/15, 15/25, or 20/30°C. (Van Der Valk 1974). Seeds are reported to remain viable for up to 2 years when stored below 40°F (Sheahan 2014). Because of the reported need for light to promote germination, seeds planted in the field should only be buried enough to prevent wind-caused movement.

The authors collected wild-grown seed from a Florida coastal plant community in late fall and minimally cleaned and non-graded seed were sown on the surface of Fafard 3B potting mix with a light dusting of vermiculite. Seeds germinated with high success within two weeks of sowing.

Seedlings remained under intermittent mist for two weeks after germination before they were transplanted, suggesting these plants do not degrade under long periods of mist exposure. Four weeks after sowing, seedlings were transferred to 4-inch pots with an amended 100% pinebark substrate and transferred to outdoor production in mid-January. By week 12, plants in 4-inch pots were large enough to have a sufficient rootball and canopy for outplanting. Plants retained in 1-gallon nursery containers began to initiate inflorescences by June.

Outplanting

Plants grown in 4-inch pots with well-developed rootballs and canopies have successfully been outplanted by the authors in late February with near 100% survival after 2 months. Plants were outplanted on backdunes, mid-slope at least 12 in from each other and from existing perennial grasses. Fertilizer application (½ tsp Osmocote 18-6-12) improved the aesthetic appearance and increased biomass for this plant but was not necessary for survival.

Literature Cited

Sheahan, C.M. 2014. "Plant Guide for seaside goldenrod (Solidago sempervirens)." USDA-Natural Resources Conservation Service, Cape May Plant Materials Center. Cape May, 08210.

Van Der Valk, A.G. 1974. "Environmental factors controlling the distribution of forbs on coastal foredunes in Cape Hatteras, National Seashore." Canadian Journal of Botany 52:1057–1073. https://doi.org/10.1139/b74-135

Poaceae

Sea oats occur throughout Florida on beach dunes and beaches and on coastal areas west to Texas and north to Maryland. Sea oats are vital dune builders that accumulate sand and prevent erosion due to wind, waves, and large storms. As sand is trapped by the long leaves of sea oats, vertical growth is stimulated, and rooting occurs at the buried nodes. This plant is extremely drought- and salt-tolerant, grows up to the high tide line of beaches, and propagates both vegetatively and by seed in the wild (Shadow 2007).

General Description

Sea oats are perennial grasses that form large colonies by extending culms upright and forming glabrous horizontal rhizomes as sand accumulates around the culms. Leaves are flat, involute at tips, up to 24 in long and 10 mm wide, and have ligule hairs up to 5 mm long. Inflorescences initiate in late spring with a single inflorescence elongating from an individual culm. Inflorescences rise above the leaves in summer, and florets of the inflorescences mature by early fall. Flowering culms reach heights of 6 ft or more and terminate in open panicles of nodding, laterally compressed, arching spikelets that become the color of straw as the outer glumes mature. Florida law prohibits the collection of sea oats inflorescences without a permit. Fruits are caryopses, and although inflorescences are present in late summer, the seed do not fully develop until fall. Sea oats produce very few seed within the large panicles, but the seed that are produced are generally viable.

Propagation

It is illegal to collect sea oats for any reason in the wild without proper permitting. Sea oats can readily be propagated from seed and rhizome fragments. When growing sea oats, minimal fertilizer and irrigation inputs is encouraged (Bachman and Whitwell 1995).

Sea oats rhizomes uprooted by hurricanes and deposited on top of soil can be salvaged as planting material within 3 days after the hurricane and stored for an initial 8 days with sufficient moisture before being planted in pots or the ground (Miller et al. 2003).

Germination of sea oats seeds has been well studied for decades. For Florida Panhandle populations, sea oats seeds require a period of cold stratification before germination, however southern Florida populations lose such requirements (Pérez and Kane 2016; Senaca 1972). Dormancy in Florida Panhandle sea oats can be broken by cold stratification for 15 to 30 days at 40°C (Senaca 1972). Near 100% germination of Florida Panhandle sea oats is possible with a 35/18°C diurnal fluctuation (Senaca 1972). A North Carolina population of sea oats seeds preferred fluctuating temperatures to constant temperatures (Burgess et al. 2002). Photoperiod neither enhances nor suppresses sea oats seed germination (Burgess et al. 2002; Senaca 1972). Sea oats seeds can be stored in airtight jars at room temperature (Nabukalu and Knott 2013) or in a refrigerator (~5°C) (Pérez and Kane 2016) for at least a year without significant loss of seed viability.

Plants grown from seed have been successfully propagated in a nursery setting under a shadehouse. The following protocol was developed by Bachman and Whitwell (1995). Place seeds (2 seeds per cell) 1 in deep within 40-cell flats with a 1:1 volume mix of peat moss and perlite. Immediately drench with fungicide (Banrot) and fertilize at recommended nursery-production rates (Bachman and Whitwell 1995). Transfer seedlings to 1-gal nursery containers with a 4:1 volume mix of pine bark and sand. Containerized plants require fertilizer and have been produced with twice-weekly liquid fertilization while others have used slow-release fertilizers at the standard gallon nursery production rates as recommended by the fertilizer manufacturer. When transplanting to containers it is important to place plants with their crowns even with the surface of the production substrate. While growing in containers, plants may require frequent irrigation.

Outplanting

Sea oats have been successfully outplanted with over 70% survival after 1 year when planted in monoculture or in conjunction with 3 other native beach dune plants (Miller et al. 2001; Stoddard et al. 2014). Transplants were seedlings grown with 4 in rootballs (Miller et al. 2001; Stoddard et al. 2014). Recent work by Hooton et al. (2014) has demonstrated a potential to enhance sea oats establishment and seedling maturation. Hooton demonstrated that wheat straw used as a surrogate wrack increased plant vigor, increased inflorescence production, and increased sand accumulation over a 2-year period compared to conventional planting without a surrogate wrack. Sea oats roots grow in mutualism with fungi that enhance their access to nutrients and moisture in the soil. Nursery production may be enhanced by the use of potting media inoculated with vesicular-arbuscular mycorrhizal fungi (Glomus sp.) (Sylvia and Burks 1988). Seedlings grown in a nursery inoculated with vesicular-arbuscular mycorrhizal (Glomus sp.) fungi had enhanced outplanting success across Florida beaches compared to noninoculated plants (Sylvia 1989).

Literature Cited

Bachman, G.R., and T. Whitwell. 1995. "Nursery production of Uniola paniculata (southern seaoats)." HortTechnology 5(4)295:298 https://doi.org/10.21273/HORTTECH.5.4.295

Burgess, T., F. Blazich, and D. Nash. 2002. "Seed germination of southern seaoats (Uniola paniculata) as influenced by stratification, temperature, and light." Journal of Environmental Horticulture 20(3):180–183. https://doi.org/10.24266/0738-2898-20.3.180

Hooton, N., D.L. Miller, M. Thetford, and S.B. Claypool. 2014. "Survival and growth of planted Uniola paniculata and dune building using surrogate wrack on Perdido Key Florida, USA." Restoration Ecology 22(5):701–707. https://doi.org/10.1111/rec.12129

Miller, D.L., M. Thetford, and L. Yager, 2001. "Evaluation of sand fence and vegetation for dune building following overwash by Hurricane Opal on Santa Rosa Island, Florida." Journal of Coastal Research 17(4):936–948.

Miller, D.L., L. Yager, M. Thetford, and M. Schneider. 2003. "Potential use of Uniola paniculata rhizome fragments for dune restoration." Restoration Ecology 11(3):359–369. https://doi.org/10.1046/j.1526-100X.2003.00006.x

Nabukalu, P., and C. Knott. 2013. "Effects of seed storage environment on sea oats (Uniola paniculata)." Ecological Restoration 31(1):16–19. https://doi.org/10.3368/er.31.1.16

Pérez, H.E., and M.E. Kane. 2016. "Different plant provenance same seed tolerance to abiotic stress: implications for ex situ germplasm conservation of a widely distributed coastal dune grass (Uniola paniculata L.)." Plant Growth Regulation 82(1):123–137. https://doi.org/10.1007/s10725-016-0244-1

Senaca, E.D. 1972. "Germination and seedling response of Atlantic and Gulf Coast populations of Uniola paniculata." American Journal of Botany 59(3):290–296. https://doi.org/10.1002/j.1537-2197.1972.tb10095.x

Shadow, R. 2007. "Plant fact sheet for sea oats (Uniola paniculata L.)." USDA NRCS, East Texas Plant Material Center. United States Department of Agriculture (USDA) Natural Resource Conservation Service (NRCS). 2017. The PLANTS Database. https://plants.usda.gov/factsheet/pdf/fs_unpa.pdf

Stoddard, M., D.L. Miller, L.C. Branch, and M. Thetford. 2014. "Endangered beach mouse: Linking population studies/habitat restoration to predict sea level rise." Final Report submitted to Gulf Islands National Seashore, Gulf Coast Cooperative Ecosystems Studies Unit Project H5000 02 A271. 130 p.

Sylvia, D. M. 1989. "Vesiculararbuscular mycorrhizal fungi associated with Uniola paniculata in Florida foredunes." Mycological Society of America 78(5):728–734. https://doi.org/10.1080/00275514.1986.12025316

Sylvia, D.M. 1988. "Selection of a Vesicular arbuscular fungus for practical inoculation of Uniola paniculata." Mycologia 80(4):565–568. https://doi.org/10.1080/00275514.1988.12025579