Frederique Beroset MBA & M.S. in Biology

Dune Irrigation: Avoid this Costly Mistake

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Irrigation Systems Harm Sand Dunes

It seems counter-intuitive, but watering the vegetation on your sand dunes is actually detrimental to the health and strength of the dune system. How is this possible? The availability of moisture close to the surface of the sand will dissuade the native plants from growing deep roots in search of water. Irrigation also encourages invasive species to propagate over the sand dune. We frequently discuss how planting appropriate vegetation on your sand dunes is necessary to anchor the dune in place. Most plants that grow along the coast (both naturally-occurring and those that were installed) have adapted to thrive in tough environmental conditions. They are very hardy, but they do require some unique maintenance such as dethatching (removal of dead plant material). However, unlike lawns and gardens, dune vegetation does not need regular watering. In fact, installing an irrigation system on your dunes will compromise the dune’s resiliency. Initially, the plants may appear lush and vibrant; but, over time, routine irrigation will kill the native vegetation, increasing the rate at which your sand dunes erode.

Deep Root Systems Build Powerful Dunes

Plants that grow along the coast are resilient by nature. They thrive in an ecosystem characterized by harsh winds, periodic driving rain, and scorching sun.  Not only do they enhance the sand dunes aesthetically, but they also fulfill a vital role in defending your property from coastal erosion. If you were to dissect a sand dune with healthy vegetation, you would find that the plants have laid down impressive web-like root systems to reach moisture located deep within the sand. Without regular irrigation, the plants’ roots will grow upwards of 30ft in search of deep water. These roots weave their way down through the sand, creating a natural net that anchors the dune in the event of a storm.  However, with the provision of a regular source of water at the surface, the plants lose the incentive to put down deep, vertical roots in favor of concentrating their root growth horizontally along the surface. This shallow root system creates a cascade effect where the sand dunes (no longer anchored by deep, complex root systems) suffer tremendous sand loss at the slightest storm.

Excess Moisture Causes Root Rot 

With easy access to water, your vegetation will redirect its focus and energies from root growth to stem and leaf production. This may not seem like an issue, but to understand why it is detrimental to the plants’ health you must first understand the continuous cycle coastal plants undergo of being buried in the sand. In this cycle, wind-borne sand repeatedly covers the base of dune vegetation. This burial cycle is critical to the plants’ survival as the deposition of sand anchors specialized stems that help propagate the plants’ root system. This cycle also buries dead organic material allowing it to decompose, under the sand, into usable nutrition for the plants. But, if the plants produce leaves at a faster rate than which the sand can bury the additional growth, the excess leaves will remain above ground and trap moisture. The damp organic material will, in turn, rot and potentially attract diseases that can weaken and/or kill the plants. 

Irrigation Attracts Invasive Species  

As detrimental as extra watering may be to plants that are native to an environment frequently subjected to droughts, this is not the case for invasive species. Invasive non-native plants will find the moisture-rich sand a favorable environment in which to grow. These invasive species are a real concern for multiple reasons. With time, these weeds will take over substantial parts of the dune by overshadowing and eventually choking out sea oats and other native plants. This is because, without adequate sunlight, native vegetation eventually dies. These non-native vines are also equipped with bean-like seed pods which, when ripe, spread their seeds far and wide. These seed pods increase the presence of weeds exponentially over time. The more water these plants receive (i.e. irrigation / regular watering of the dune) the faster and further they grow.

Consequences of Weed-Whacking

 Once the weeds take hold of your sand dune, the process of extracting them is difficult and requires delicate pulling in order to avoid uprooting the native vegetation. We strongly DISCOURAGE the use of weed whacker-type trimmers to manage the weeds. The end result will be a thick mat of decaying vegetation and a massive broadcast of the seeds. It may seem like an efficient short-term solution, but by next summer the rapid growth of vines will choke out the beneficial vegetation and spread to neighboring properties too.

Have an Irrigation System? Turn It Off!

In order to avoid these nightmare scenarios, we recommend that you avoid watering your dunes altogether. If you choose to water, we suggest that it be NO MORE than once a week. And, always be on the lookout for invasive species.  If you are working towards reversing the effects of installing an irrigation system and need help identifying intrusive species, reach out to us. As you develop a greater understanding of how sand dunes work, you will gain confidence in employing the necessary steps in order to create a thriving dune ecosystem. Remember, coastal plants are not the same as conventional yard/garden plants. They need care that is specifically tailored to their needs if they are to offer your property any kind of protection in the event of a storm. Aside from saving your dunes, not irrigating will save you money. 

How You Can Help Save Baby Sea Turtles

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It’s Time for a Sea Turtle Baby Shower!

Mid-July, from beneath the sand all along the Florida and Alabama coast, hatchlings (baby sea turtles) began their journey to adulthood. Witnessing the turtles emerge from their nests and scurry to the water is a bucket-list experience for most beach lovers. With all the strength they can muster, the babies will have to brave enormous odds before finding safety in the open ocean. Relying on their sheer volume for protection, the hatchlings move in unison to overwhelm predators who lurk nearby. Those hatchlings who successfully make it to the crashing surf will have to swim long distances to make it past the coast. In the open water of the Sargasso Sea (an area of the Atlantic Ocean off the east coast), safety lies in free-floating seaweed. These island-like masses of algae function as nurseries in which the hatchlings can mature into adulthood. But, only a few will survive this dangerous journey. This is why we should do our best to provide safe passage for these hatchlings.

How Long Does the Incubation Period Last?

Buried out of the tide’s reach, thousands of sea turtle nests, from five different species, line the coast of Florida and Alabama. According to an in-depth Q&A provided by the Sea Turtle Conservancy, the average incubation takes 60 days and varies by species. During incubation, sand temperature greatly impacts two important aspects of embryo development. First, it dictates the speed of the process. The higher the sand temperature surrounding the eggs, the shorter the incubation periods. Second, the temperature of the sand impacts the ratio of the sex of the hatchlings. Cooler temperatures yield clutches (a group of eggs) with a higher male count while warmer temperatures tend to produce more females.

sea_turtle_boil

After Incubation Comes Digging!

Once incubation is complete, the hatchlings break out of their eggs using a temporary tooth called the caruncle located on the edge of their mouth. The eggshell has a soft, leathery texture and is roughly the size of a ping-pong ball. After hatching, the baby turtles remain under the sand for a number of days. During this time, the first few to exit their eggs, stimulate the others to do the same. According to SEE Turtles, before the babies can surface, each hatchling absorbs the remaining yolk attached to its umbilical cord. The yolk, an essential source of nutrients, is vital in providing the newly-hatched sea turtles with the necessary energy to dig, crawl, and swim their way offshore.

What Can You Do to Help the Hatchlings?

In order to achieve higher odds of survival, the hatchlings climb out of their nest in groups and huddle under the surface until the temperature of the sand cools. Cooler sands typically indicate that it is nighttime when hatchlings are less likely to overheat or be preyed on. By swarming out together, the hatchlings strategically overwhelm nearby predators. Raccoons, birds, lizards, crabs, dogs, wild pigs, coyotes, dolphins, sharks, and a variety of carnivorous fish all prey on the hatchlings. In addition to these predators, human activity also adds a complicated layer of obstacles for the hatchlings to overcome. The Sea Turtle Conservancy (STC) offers a list of steps you can take next time you visit the beach.

  • Remove any leftover trash on the beach. These sources of food may attract unwanted wildlife that may destroy the nests.
  • Avoid leaving pet food (intended for domesticated animals) outside as these food sources also may attract predatory wildlife.
  • Remember to minimize obstacles on your coastal property. Fill up holes, knock down sand structures, and remove beach accessories such as tents and umbrellas. Baby sea turtles that get trapped by these obstacles will most likely be eaten. 

S.T.O.P. Beach Front Lighting!

Scientists observe that sea turtles exhibit phototactic behavior. This means they are attracted to light. The hatchlings appear to be guided by instinct to scurry towards the brightest light around—believing it is the moonlight reflecting off of the ocean. Unfortunately, on coasts that contend with heavy light pollution, hatchlings have been observed to migrate inland, away from the sea, often to their premature death. When hatchlings are found moving towards the city lights they are deemed ‘disoriented’ and must rely on volunteers (if there are any present) to redirect them to the water. According to the Sea Turtle Oversight Protection (S.T.O.P.), one in three hatchlings move inland towards artificial lights instead of towards the ocean. However, through the volunteer efforts of S.T.O.P., the hatchling death rate has gone down by 50% in Broward County where the program is active. Volunteers closely watch the nests and make sure to move disoriented baby sea turtles to the sea. In order to lessen the chance of turtle disorientation on your property, dim your beach-front lighting as much possible.

How Many Sea Turtle Hatchlings Survive?

Based on the estimates provided by the National Ocean Service and Florida Fish and Wildlife Conservation Commission, roughly 60,000 nests will be laid along the Florida coast this year. Assuming 70% of all sea turtle hatchlings survive incubation at 100 eggs per clutch, that would produce an initial hatchling population of roughly 42,000. By applying the survival ratio to that population number, a high estimate of only 42 baby turtles from this turtle nesting season will survive to sexual maturity.

If You Find a Sea Turtle, Please Call!

If you come across an adult or a hatchling, please remain at a distance, do not flash any bright lights at it, and immediately call your local sea turtle initiative to report your finding. Do not disturb the animal. Frightened pregnant females may return to the water without nesting. Also, do not touch the turtle’s track marks, as scientists use these as a means to locate the nest and identify the species that laid it.

If you come across a sea turtle, whether it is dead, sick, stranded,  injured, or even if it seems fine, do not touch the animal. Call your local Sea turtle Initiative and report the incident.

The STC provides a list of questions that you should be prepared to answer when reporting the animal:

  • “Where is the exact location of the animal?”
  • “Is the turtle alive or dead?”
  • “What is the approximate size of the turtle?”
  • “Is the turtle marked with spray paint? (This may indicate that the turtle has been previously documented.)”
  • “What is the location of the closest access point to the turtle? 

Depending on location, here is a list of sea turtle emergency responders:

State Authority Number
Alabama Alabama’s Sea Turtle Conservation Program 1-866-Sea-Turtle

(1-866-732-8878-53)
Florida FWC’s 24-hr hotline 1-888-404-3922
Georgia Georgia Stranding Hotline 1-800-272-8363
North Carolina NMFS SEFSC Beaufort Laboratory Hotline 1-800-922-5431
South Carolina South Carolina Stranding Hotline 1-800-922-5431

 

If you are outside of the regions listed above, you can report a stranded or injured marine animal to the NOAA Fisheries by following this link.

Cleaner Beaches Make Happy Turtles!

The spectacle of watching baby turtles hatch, and make their way to the water, is an emotional experience. Those who are fortunate enough to observe this event will never forget it. Undeniably, these two-inch-long turtle hatchlings are incredibly strong and must brave enormous odds at a very young age. It is our duty, as coastal stewards, to protect and facilitate the hatching process as much as possible. One of the most impactful ways to help sea turtles and other at-risk species is to participate in beach cleanups. For updates on local cleanup efforts in your area, follow this link for more information. Also, check-in with your local sea turtle conservation effort to see if you can participate in any upcoming hatching events. Through mutual effort between conservation initiatives and coastal communities, we can work towards higher survival rates for the sea turtles that also call our shores home.

 

References:

SEE Turtles, www.seeturtles.org/baby-turtles.

 

Sea Turtle Conservancy, conserveturtles.org/information-sea-turtles-frequently-asked-questions/.

 

Florida Fish And Wildlife Conservation Commission, myfwc.com/research/wildlife/sea-turtles/florida/faq/.

 

“Sea TurtleOversight Protection.” HOME – Sea Turtle Oversight Protection, www.seaturtleop.com/.

 

Sea Turtle Conservancy, conserveturtles.org/nesting-season-is-may-october/.

 

Fascinating Facts, 16 June 2015, oceanservice.noaa.gov/news/june15/sea-turtles.html.

A Guide to Turtle Nesting Season: How to Prepare

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Turtle Nesting Season has Two Sections

Five different species of sea turtles nest on beaches along the gulf coast every summer during turtle nesting season, and 90% of those turtles will do so along the coast of Florida and Alabama. Kelly Reetz (an Alabama Gulf State Park Naturalist) reports that turtle season lasts from the first of May through the end of October. The season is divided into two timelines. She states that from the beginning of May to the end of August, adult female turtles nest. While from mid-July to the end of October, the eggs hatch. Communities in nesting areas are preparing to welcome these reptile mommas. We encourage you to download this pdf guide by the Fish & Wildlife Service and read it for more information on how to enjoy the beach while being protective of your marine neighbors. There are many ways you can help these lovely creatures. From reducing coastal lighting to adopting a turtle, we invite you to join forces in employing ways to help ensure the 2019 nesting season goes smoothly.

Leave No Trash Behind on The Beach

According to the Sea Turtle Conservancy (the world’s oldest sea turtle conservation and research organization), there are a few steps every coastal property owner should take to provide successful nesting grounds for the turtles. The sea turtle eggs and hatchlings face a wide variety of predators. One of the leading causes of hatchling deaths are raccoons. These predators destroy thousands of sea turtle nests every year. We should do what we can to minimize predator presence. First, proactively remove any leftover trash on the beach that will attract unwanted animals. Next, avoid leaving pet food (intended for dogs and cats) outside. These food sources attract wildlife that may impact turtle nests.

Do Your Best to Dim Beachfront Lights

In addition to routine trash removal, the Sea Turtle Conservancy urges property owners to avoid bright lights on the coast. Scientists theorize that sea turtles are phototactic (attracted to light). They appear to be guided by an instinct to follow the brightest light–believing it is the moonlight reflecting off of the ocean. However, due to coastal light pollution, thousands of hatchlings and adult turtles become disoriented by the presence of these bright, unnatural lights. This causes them to move inland (instead of out to sea) –often to their premature deaths. The Sea Turtle Conservancy also shares that sea turtles are nocturnal nesters and seek dark locations to lay their eggs. As of 2017, the Florida Fish and Wildlife Conservation Commission (FWC) requires that all cases of hatchling and adult female disorientation be recorded. There is a live tracking app with daily updates of every documented disorientation event on the Floridian coast.

Turtle Disorientation Cases in Florida

The bottom line is that counties with strict lighting regulations report fewer turtle disorientations. To illustrate this, refer to the FWC report for the number of documented disorientation cases of loggerheads in Florida per county from 2013 through 2017. Okaloosa County shifted towards using sea turtle-friendly lights and had zero disorientation cases for adults and only one case of hatchling disorientation in 2017. By comparison, Broward County ranked highest out of all Florida counties in 2017 with documented disorientation incidents at 805 total affected turtles- 764 hatchlings and 41 adults. Communities that deal with heavy light pollution opt to relocate the nests to darker grounds. In 2018, Panama City Beach reported that 72% of all its hatchlings were found moving inland. Therefore, to improve the hatchlings’ odds of survival, they contracted volunteers with Turtle Watch to monitor the nests and safely move them to a darker beach. Check out the FWC report to see how different Florida counties are ranked by its number of disorientation cases for leatherbacks and green turtles. Also, you can team up with your local preservation effort and apply in early 2020 to the Sea Turtle License Plate Grant for financial aid for Florida marine turtle permit-related activities.

What Is the Sea Turtle Nesting Process Like?

The anatomy of sea turtles and their reproductive instincts are part of what makes these animals so fascinating. According to an in-depth Q&A provided by the Sea Turtle Conservancy, sea turtles lay an average of 110 eggs in a single nest and lay multiple nests per season. That’s a lot of eggs, just for one turtle! Once female turtles select the exact spot for their nest, they dig a body pit using all four flippers and then construct an egg chamber by slowly scooping away sand using their back two flippers. The egg chamber is an impressive structure for an aquatic animal that does not usually burrow and is located two feet below the soil’s surface.  Once the chamber is complete, the turtle’s ovipositor (an egg-laying organ) begins contracting and depositing one to four eggs. When the turtle is finished, she covers both the nest and her trail to lessen the chance predators will find the eggs. Sea turtles must nest on land because the eggs breathe through a membrane that cannot be submerged in water.

How Often Do Sea Turtles Nest?

The nesting frequency of sea turtles is unique to each species*

Number of Nests Interval between Nests
Loggerheads 2-3 nests 2-3 weeks
Green Sea Turtles 3-4 nests 2-3 weeks
Leatherbacks 5-7 nests 10 days

*Data provided by the Broward County Conservation Program

Sea turtles do not nest yearly but every second or third year. If the circumstances are favorable, they will nest within five to thirty-five miles from the region where they were hatched or have nested in the past. Several factors influence the frequency of sea turtle nesting, including the environment, food availability, genetic factors, presence of parasites, and other variables. Female sea turtles do not return to any of their nests. Once a hatchling is born, it is entirely on its own.

What Is the Mating Process Like?

Generally speaking, sea turtles are solitary creatures. They usually only come together to mate. Depending on the species, sea turtles reach sexual maturity between 10 to 50 years after hatching, according to a sea turtle life cycle fact sheet provided by SEE Turtles (a conservation group that helps protect turtles through ecotourism). After hatching, sea turtles venture out during their pelagic (open sea) phase. This phase of a sea turtle’s life cycle is also commonly referred to by scientists as the “lost years.” This name is a result of how difficult it is to track the movements of the young turtles while they forage over large areas of the open ocean. Once they reach sexual maturity, the sea turtles migrate back to the coast to mate and nest. Female sea turtles will mate with multiple males until they have collected enough sperm to fertilize all of their clutches (the number of eggs in a nest) for the season.

Sea Turtles Face Significant Risks

Under the U.S. Endangered Species Act (ESA), all sea turtles found in American waters are designated as threatened or endangered. When deemed threatened, the species is considered likely to become endangered. When a species is labeled as endangered, they are designated at risk of extinction. Sea turtles encounter both onshore and offshore challenges that are difficult to overcome. Many prime sea turtle nesting sites have been reduced or destroyed by extensive development. To protect the species, coastal communities need to be mindful of onshore activities in nesting zones.

Volunteering Opportunities for This Upcoming Summer

This season, consider volunteering with your local conservation group. Stay in a cozy cabin or cottage close to the sea turtle action at Gulf State Park. If you are looking into overseas travel destinations, ecotourism is a way to volunteer while enjoying your vacation. Follow this link for a list of international sea turtle conservation organizations that need your help. Because these animals nest on beautiful beaches, working with sea turtles is fun and rewarding! Whether your contribution is simply picking up trash left on the beach or taking time off from work to volunteer in an ecotourism event, every effort counts towards achieving the long-term goal of sea turtle preservation.

Sources:

“Disorientations.” Florida Fish And Wildlife Conservation Commission, myfwc.com/wildlifehabitats/wildlife/sea-turtle/lighting/disorientations/.

“Life Cycle of A Sea Turtle.” SEE Turtles, www.seeturtles.org/sea-turtle-life-cycle.

“Sea Turtle Nesting Behavior.” NSU, cnso.nova.edu/seaturtles/nesting-behavior.html.

“Tips for Sea Turtle Nesting Season May – October – Sea Turtle Conservancy.” Sea Turtle Conservancy, 1 May 2018, conserveturtles.org/nesting-season-is-may-october/.

Dethatching: Healthy Sea Oats build Resilient Shorelines

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Along the eastern seaboard and Gulf states, sea oats help limit coastal erosion. Dune vegetation is one, if not the most crucial, part of the successful building and stabilization of dunes. Unlike other plants, they can thrive on the beach because of two properties: a robust root system with a web-like quality and the ability to continue to grow upwards despite being repeatedly covered in sand. Through this cycle of sand accretion, the plant actively expands its root system and widens the hurricane defense barrier. Sea oats are so instrumental to the sustainability of our beaches that the plants receive government protection in most states. Sea oats stabilize the dune allowing the ecosystem to thrive, and to maximize the plant’s effectiveness, routine maintenance is advisable.

Sea Oats are Critical to help limit Coastal Erosion

Sand Dune with and without vegetationThe image to left depicts a  dune  partially covered in vegetation. The section that is bare lost $5,000 to $7,000 worth of sand due to enormous erosion brought on by a storm. However, if you look closely, you can observe roots sticking out of the cliff. This growth indicates that the adjacent plants’ web-like root systems that are 15 ft away helped hold the remaining sand in place. Healthy sea oats can help you avoid tremendous loss by anchoring your protective berm in the face of coastal storms.

How Do Sea Oats Anchor the Dunes?

While there are many types of plants that protect against coastal erosion, sea oats are the most prevalent (and critical) species along the coast in America. According to a fact sheet provided by the USDA, mature sea oats’ leaves reach about 24 inches in length and their flowers reach about 6 feet in height. At the base of the plant, there are special stems that have bulges or nodes. These bulges will “root down and anchor to the soil surface” as the wind carries sand over the plant. Sea oats also produce rhizomes that are, in part, responsible for the plants’ expansion and colonization of the dunes. Those rhizomes also help strengthen the thick mesh-like quality of the plants’ complex root system. Sand accretion stimulates the plants to grow sideways by pinning down these stems and encouraging new root systems to grow from its nodes. The sand burial cycle is critical because it encourages the plants to fight for their survival by pushing through the particles of sand with their new stems widening the plants’ grip on the sand dune. Most importantly, it buries any dead organic material from the plants and allows it to decompose, under the sand, into nutrition that seeps down to the roots.

What is Thatch?

Sea oats are sometimes susceptible to the accumulation of thatch (dead plant material) around the base of the plant. This buildup proves detrimental to the plant’s health and jeopardizes the role the plant plays in the dune’s ecosystem. Thatch is a form of mulch. Mulch can be comprised of many substances–dried plant material, wood chips/bark, coconut husks, gravel, even shredded rubber. The function of mulch is to keep moisture in the ground. On the dunes, thatch is composed of the plants’ dead/spent leaves and stems that remained above the sand. This buildup forms a mass of dead plant material that mats together in a clump resembling a ball of yarn at the base of the plant. One might assume thatch would be beneficial to the plants (by providing nutrients and moisture retention) and should therefore not be removed. However, if thatch accumulates faster than sand accretion can bury it the sea oats can reach a plateau in their growth.

How does Thatch Adversely Affect Dune Vegetation?

Sea oats stabilize the dune they grow on by sending out deep roots in search of water. But, in order to do so, the plants need nutrients that can support this endeavor.  A buildup of thatch creates multiple problems: it encourages shallow roots, does not decompose into nutrition for the plant, and can harbor diseases and pests. This clump of rotting organic material concentrates moisture at the surface of the soil. With access to a shallow water source, the plants no longer need to send out deep roots and offer no protection to the dune. When left unburied, thatch cannot decompose to become the nutrients the plants need to grow throughout the dune. Thatch creates an environment favorable for diseases to proliferate, often proving fatal to the plant. Furthermore, the buildup provides a place for non-native rats and snakes to lay claim to the dunes. If you are noticing an increase in snakes around your property, check out our comprehensive guide on how to address this issue.

Sea Oats on the Dunes’ Slope Are Most at Risk

When observing a constructed dune, typically, the sea oats at the base of the dune are the tallest and strongest. The plants on the dune’s slope tend to be shorter and less robust by comparison. The main difference between the two plants is that the sea oats at the foot of the slope undergo the process of cyclical sand accretion while the plants on the slope remain unburied. Thatch begins to accumulate at the base of the plants on the slope as their spent leaves and stems remain above the surface of the sand. The presence of high moisture at the sand’s surface (from this thatch/mulch), in turn, causes the plants to develop shallow root systems and stunted growth. These plants become weak and very easy to uproot. The sea oats growing on the incline of the slope are critical to holding the formation in place just as the ones present at the base of the slope are critical to expanding the dune. Since those plants do not go through the cycle of getting buried, they are the ones that most need maintenance.

Dry Thatch Poses a Fire Hazard

In a long period of drought (when rain does not wet the accumulated thatch), the thatch dries out, making it extremely flammable. This dry thatch poses a significant fire hazard that a cigarette butt, 4th of July fireworks, or other accidental sparks can easily ignite. According to Panama City News Herald, in 2018, roughly 1.5 acres of federally protected land by the Destin bridge caught on fire due to illegal firework activity. The fire spread quickly as various emergency response teams attempted to stop it. Properties that do not regularly dethatch may be at an increased risk of undergoing a similar fate.

Academic Efforts to Protect Sea Oats

With the ability to thrive in saline environments with high temperatures, droughts, and temporary inundations, sea oats help defend the shoreline against erosion. For the Alabama and North West Florida Coast the 2004 & 2005 hurricane seasons were a wake-up call in that the storms damaged or destroyed much of the natural sea oats population that serve as seed sources to generate new plants. Because of how critical the plant is to dune preservation, Michael Kane an environmental horticulture professor for the University of Florida, spearheaded a project to cryogenically freeze thousands of sea oat samples from all major sea oat populations along Florida’s coast. In addition to this particular sea oats library, other universities ensure that genetic variety is kept with banking seeds from different areas. The importance of this plant for dune preservation cannot be overstated and should be protected for future generations.

Leave the Maintenance to Professionals

We have discussed the importance of removing thatch, but not everyone is qualified to remove it. Since very few plants can grow as their bases are covered, sea oats are accustomed to anchoring themselves with “dense root webs.” When thatch accumulates, sea oats are in a weakened state and are more likely to be accidentally pulled from the soil. Therefore, it is highly recommended that only a team of qualified professionals, who have a working understanding of the plant’s nature, be the ones to remove the accumulated thatch. Sea oats are vital to successful dune preservation. It is our job as Coastal Stewards to protect and nurture them to the best of our ability. If your dune vegetation is undergoing the cycle of sand accretion, then mother nature handles the dead organic material. However, if you are in a situation where your plants are not undergoing natural sand accumulation, you should get professional help.

Sources:

“Freezing Sea Oats.” Florida Sea Grant, 27 Sept. 2017, www.flseagrant.org/news/2012/09/sea-oats/. ,

Osbourne, Heather. “Fire Chief: Fireworks Likely Started Destin Fire.” Panama City News Herald, Panama City News Herald, 6 July 2018, www.newsherald.com/news/20180706/fire-chief-fireworks-likely-started-destin-fire.

R. Alan Shadow. Plant Fact Sheet SEA OATS. Plant Fact Sheet SEA OATS, plants.usda.gov/factsheet/pdf/fs_unpa.pdf.

The Do’s and Don’ts of Fertilization on Sand Dunes

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From blue whales to microscopic organisms, every living thing on earth must eat to survive. Coastal plants are no exception! It is common knowledge that plants first need air, water, and sunlight. But, for sea oats to access the water deep within the dunes, they need a deep root system. Strong root system development requires an adequate nutrient source. Sand is generally a nutrient-poor soil. Whether the sand can naturally provide vital nutrients to the vegetation depends partly on the sand’s composition, which varies by location. Sometimes, to encourage the development of healthy dune vegetation, special fertilizer needs to be applied to the soil.

How Does Sand Composition Vary Along the Gulf Coast?

From a nutrient standpoint, Texas’ beaches boast ideal sand composition because two sources readily provide new sediment and nutrients to its coastline: the Mississippi River and in-state rivers. The World Ocean Review, an international publication of oceanographic science reports, states that the Mississippi River empties vast amounts of sediments and nutrients into the Gulf of Mexico and wind carries the content westward along the shoreline. In addition to the silt from the Mississippi, according to the American Geological Society, Texas has different primary in-state rivers that deliver a “distinct suite of heavy minerals” to the coast. These diverse sediment sources are what make Texas sand a very rich soil with nutrients easily accessed by the coastal plants’ roots.

At the direct opposite end of the nutrient spectrum are the beaches located to the east of the Mississippi. The sand along the eastern shoreline of the Gulf Coast is known throughout the world for its aesthetic qualities white, soft, and pristine. This “sugar-white” sand is primarily composed of quartz crystal a mineral resistant to chemical and physical weathering. However, the University of Florida states that, unlike Texan sand, the quartz particles present on the shoreline do not “hold water or nutrients very well.” Nutrients cannot chelate to the smooth quartz particles. Texas beaches do not require fertilization, but beaches mainly comprised of quartz do. The fertilizer, however, needs to be specifically tailored to the needs of the plants that grow on the dunes and designed to function with quartz sand.

Where Does White Sand Come From?

quartz-crystal

The generally-accepted theory is that the quartz, located on the gulf coast, arrived there through extensive erosion of the rock formations from the Appalachian Mountains. Rivers carried inland sediments into the Atlantic Ocean and the Gulf of Mexico. However, over time, the large rivers shifted, cutting off the supply of new sand to a large section of the Gulf Coast. The continual churning motion of the tide and chemical reactions in the water eroded all of the weaker minerals and only crystal quartz remained on these beaches. In an interview in 2017, Stephen Leatherman a geologist and coastal scientist, explained that Florida’s beaches reached an “ecological equilibrium” when the quartz weathered down to its “terminal size” and became “trapped by the action of the waves.” The crystal quartz gives the sand a white color and sugar-like consistency. In combination with the sunlight, the sand reflects through the water giving waves the beautiful emerald color for which the quartz-comprised beaches are known.

How Does Beach Raking Impact Sea Oats?

Close up of seaweed rake

While these pristine beaches are incredibly relaxing to look at, their composition makes it difficult for plants to grow. One of Mother Nature’s methods of fertilizing coastal plants is by routinely depositing seaweed on the coast. According to a dune management guide put out by the Department of Environmental Resources Management of Palm Beach County, seaweed “creates a nutrient-rich organic layer” that feeds the animals and plants that live on the shore. However, to both prevent the unpleasant aroma of decomposing seaweed and return the beaches to their pristine condition, humans routinely remove the deposited seaweed before it has a chance to decay. This process is called beach raking and is part of why the fertilization of the sea oats becomes a vital part of maintaining healthy  dunes.

When Should You Fertilize Sea Oats?

When growing in nutrient-poor conditions, two other situations contribute to the sea oats’ need for fertilization—the initial planting and the process of dethatching. Both circumstances are stressful to sea oats as both instances see plants with shallow root systems. Dethatching is the process by which thatch is removed from the base of the plants. Thatch is an accumulation of dead/spent organic material, which is detrimental to sea oats because it holds moisture at the surface of the sand. This causes the plant to develop a shallow root system that will not adequately anchor the plant to the dune. It may also cause the plant to rot as the thatch layer encourages an environment prone to disease development.

Once the thatch is removed, water availability is no longer shallow, and the plant’s root system needs to be encouraged to grow deeper in the soil in search of a new water source. Slow-release fertilizer provides the nutrients necessary for the plant to develop a strong network of webbed roots to find water and to anchor the dunes in place. This specific fertilizer helps the plant achieve this growth by delivering small amounts of nutrients in the soil over time. A publication on dune restoration by North Carolina State University warns against excess fertilization, stating that it may “damage the development” of the plants and “increase the occurrence of plant diseases.” The fertilizer will be best absorbed during the growing season. We recommend one application of fertilizer in late Spring and one in late summer/early fall. Because of their deep, web-like root system, sea oats are of paramount importance in the building and maintaining of sand dunes. For this reason, sea oats are federally protected due to their integral role in dune preservation.

What Kind of Fertilizer Do Sea Oats Need?

Fertilizers, as a plant growth enhancer, vary in purpose. They are formulated to focus on one (or more) of four distinct functions within plants. Certain formulas strengthen the roots or create denser foliage, while others encourage flower production and fruit yield. When the goal is to strengthen a dune system, the primary purpose of the fertilizer should be to help the plants develop strong, deep roots. The fertilizer applied should be slow releasing and specific for sea oats. For these reasons, applying a general fertilizer (intended for gardens) on the dunes can be extremely detrimental to the health of the fragile dune ecosystem. These all-purpose fertilizers may create the illusion of a healthy environment because the plants above the ground look thriving. Still, below the ground, the root systems are weak and debilitated. Avoid creating environmental hazards by entrusting professionals who have extensive knowledge in this domain to fertilize your dune system.

Strong root systems = Resilient Dunes.

Sources: 

Broome, Stephen. “Restoration and Management of Coastal Dune Vegetation | NC State Extension Publications.” Restoration and Management of Coastal Dune Vegetation | NC State Extension Publications, content.ces.ncsu.edu/restoration-and-management-of-coastal-dune-vegetation.

Bullard, Fred M. “Source of Beach and River Sands on Gulf Coast of Texas.” GSA Bulletin, GeoScienceWorld, 1 July 1942, pubs.geoscienceworld.org/gsa/gsabulletin/article-abstract/53/7/1021/3939/source-of-beach-and-river-sands-on-gulf-coast-of?redirectedFrom=fulltext.

Palm Beach County Board of County Commissioners. Guidelines for Beach & Dune Management. Guidelines for Beach & Dune Management, discover.pbcgov.org/erm/Publications/BeachandDuneManagement.pdf.

Ronson, Jacqueline. “The Best Sand on Earth Is This, According to Dr. Beach.” Inverse, www.inverse.com/article/32767-best-beach-sand-fine-white-quartz-crystal-siesta-florida.

“The Mississippi River and the Gulf of Mexico Dead Zone « World Ocean Review.” World Ocean Review, worldoceanreview.com/en/wor-1/pollution/over-fertilization/the-mississippi-river-and-the-gulf-of-mexico-dead-zone/.

“Working in Your Florida Soil.” Working in Your Florida Soil – Gardening Solutions – University of Florida, Institute of Food and Agricultural Sciences, gardeningsolutions.ifas.ufl.edu/care/planting/florida-soil.html.

The Dune Doctors’ New Face

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Over the past several years, Dune Doctors LLC has steadily grown as we completed projects of varying sizes and needs along the coast. Moving forward, we plan to expand our services to areas of the USA we have previously not reached. To reflect these aspirations, we decided to transform our brand to mark the beginning of a new decade for our company. In rebranding, we are centering our identity on being leading experts in dune restoration.

The coastline is constantly changing, and Dune Doctors will evolve to match its needs. Humans and nature are often at the mercy of each other’s hand. However, when we are mindful of preserving the ecosystem around us, nature, in turn, protects us in kind.

Dune Doctors encourages people to embrace their responsibility to regard the natural coastal environment as a valuable asset that must be invested in, respected, and cared for.

“We believe when people know better, they do better.”

We are passionate experts dedicated to educating and inspiring others to be stewards for their coastal surroundings for generations to come. Using our talents, tools, and scientific background, we employ methods based on proven research. We design personalized coastal erosion and preservation solutions built for beauty and long-term resiliency.

As a dedicated team of professionals, we pride ourselves on striking the balance between our clients and the coast. Through empowered stewardship, we aim to help you Preserve, Protect, Optimize, and Maintain your dunes for years to come.