Skip to content

American Beach: The Earthcache EarthCache

Hidden : 1/3/2013
Difficulty:
1.5 out of 5
Terrain:
1.5 out of 5

Size: Size:   not chosen (not chosen)

Join now to view geocache location details. It's free!

Watch

How Geocaching Works

Please note Use of geocaching.com services is subject to the terms and conditions in our disclaimer.

Geocache Description:


To receive credit for this EarthCache, you will need to answer a few questions. Hopefully by doing so, you will have a better understanding of the incredible forces that led to the formation of this sand dune

E-mail this information to me when you log this EarthCache. You do NOT have to wait for confirmation from me before logging your find. Please do not make any reference to these answers in your log.

1. What is the name of the sand dune?
2. How tall is the sand dune?
3. In your opinion, What zone is the sand dune in?
4. What is the nickname of the person who fought to preserve the sand dune?
5. Totally optional. Take a picture of yourself with the sand dune in the background.

The dune system that you are visiting is the tallest dune in Florida and is part of the last undeveloped dune system in the state.

The sand dune is located in the Timucuan Ecological and Historic Preserve.

Please do not cross over the boundary. You can admire her from afar. All info needed to complete this Earthcache is provided at the given coords located in the Nassau County right of way and on the cache page.

Parking is available, the coords are listed below. The parking area is a .2 mile hike one way. There is alternate parking just use your judgement.




SAND DUNES
Dunes play an important role both to the beaches that front them and the land behind them. Dunes act as a sand reserve for beaches. Dune systems act as a buffer between the high energy of the ocean and the land. Dunes provide a barrier to salt intrusion from high tides and storm surges, and it protects the land behind the dunes from erosion.

The dunes in Florida are broken into five zones. These zones become more stable and are older as you move away from the beach. These zones are the pioneer dune zone, the fore dune zone, the dune field zone, the scrub zone, and the hammock zone.

The pioneer dune forms just above the highest tides. They are formed by windblown sand collecting around an obstruction. As organic matter is deposited by wind and waves, low herbs (e.g., sea-rockets, seaside evening-primrose) colonize the dune. As these plants collect more sand and organic matter, the dune increases in height becoming the fore dune.

As the fore dune grows it is colonized by sea-oats, railroad vine, sand spurs, beach croton, beach morning glory, and other plants. These low, tough plants have extensive root systems, which stabilize the dune.

Dune fields are formed as a series of older, stable fore dunes grow in height and organic content. The dune field will absorb much of the energy from storm surges, thereby protecting the land behind them.

When enough organic material has been collected, woody plants such as the palmetto, wax myrtle, cabbage palm, and sea grapes colonize the dunes. This creates a dense scrub zone. The oldest dunes may be colonized by trees such as the live oak and slash pine to create a maritime forest known as a hammock.

The plants found on the pioneer and fore dune must be particularly tough. These plants grow in sandy, salty soils with little water or nutrients. These plants must be able to withstand salt spray, burial, wind, heat, and drought. These plants have deep extensive root systems to anchor the plant and search for water. These plants, much like desert plants, have special adaptations to conserve water. Dune plants have a wide variety of methods for dealing with salt. Some plants limit salt penetration with methods such as thick, waxy cuticles or epidermal hairs. Other plants excrete the salt. Some can even detoxify the salt within their system. Without these hardy plants to hold the sand in place, so close to the high energy beach, there would be no dune system.

The pioneer and fore dune play an important part in controlling beach erosion. During the low wave energy summer months, sand is deposited on the beach and blown into the dune system for storage. During high wave energy periods when the beach is eroded, the pioneer and fore dunes erode giving their sand back to the beach to increase its profile. This keeps the beach from completely eroding away and washovers from occurring. As sand is deposited on the beaches the next summer the wind replenishes the dunes.

Beach erosion is a big problem in Florida. All along the Florida coast you can see that areas that were built directly on the dune are more eroded than the areas were the dune system is still intact.

I would like to thank

Geocaching.com for having EarthCache style caches
The Geological Society of America and the EarthCache Team
www.floridaocean.org for the great information on Florida sand dunes

Additional Hints (No hints available.)