Many of our members with oceanfront property, especially those who have never lived on the ocean, look for information about how to properly maintain their dunes and where to find professional guidance. The City follows the recommendations below from Robert Barron, a local dune expert who designed and installed most of the dune landscaping in Delray Beach.
- Removal of invasive exotic pest plant species.
Exotic species compete with and overwhelm more stable native dune plants but are often weaker and more likely to suffer damage during a storm, and break up and deliver missiles which may damage property. These should be carefully removed as the first step in dune landscape management, but not until a program is in place to replant cleared areas with more appropriate native species.
- Cultivation and support of a dense grassy pioneer zone dune.
The foredune is the first line of defense against erosion. Sea oats and fast growing, deep rooted grasses capture wind blown sand and help to hold the sand against wave attacks. Regular care may be necessary to promote dense growth, especially in critically eroding areas, or spots which conflict with recreation activity. All areas cleared of invasive exotic plants should be quickly replanted with pioneer zone grasses.
- Remedial and maintenance pruning of native strand/scrub zone species.
In the stable natural condition, the nearshore dunescape immediately upland of the grassy pioneer zone had no trees. The wind resistant Coastal Strand Zone, populated by saw palmettos and low shrubs, should be maintained at knee to hip high to reduce uprooting and toppling forces during a windstorm. Where shrubs have been allowed to grow taller, initial pruning should be 24 to 30 inches below the desired maintenance height to allow for growth of branching sub structure (an arboricultural process called coppicing). Long term maintenance pruning should be at hip height, balancing wind resistance with ease of maintenance.
- Supplemental planting of the Strand Zone with a diversity of native species, dominated by saw palmettos.
Areas cleared of exotics and exposed by reduction of tall native plant canopies should be replanted with a mix of native species which existed in the dune before development. Initially this should be the pioneer zone community dominated by sea oats and dune panic grass. Rare and established species may be included to restore a complex, historically correct population. Once established, these should be pruned to maintain low shrub height. Pre-existing native trees may, in limited areas, be maintained in tree form to provide shade.
- Active, aggressive enforcement of ordinances to eliminate light pollution.
Execution of any Dune Management Plan requires permitting by the Florida Department of Environmental Protection. Such permits are contingent upon demonstrating that no additional light from upland development will reach the marine turtle nesting beach, as a result of implementation of the plan. Problems with marine turtle disorientation will be prevented by considerate project design and by active nighttime inspection and concerted enforcement of Local, County, and State Laws.
While a member of the city staff, Rob was responsible for establishing the existing dune system and now contracts to assist in dune management for the city. He has completed more than 1500 dune projects since 1974, and continues to professionally consult and advise on dune management and turtle lighting issues throughout Florida and the Caribbean. He can be reached at firstname.lastname@example.org or 561-441-1446.