VEGETATION FOR DUNE BUILDING AND STABILZATION

Historic Dune Plant Commercial Production & Availability in

North Carolina

• Studies initiated on east, gulf, west, and Great Lakes coasts by National Park Service, USDA, USACE and others in the early to mid 1900’s

• New interest in NC was aroused following hurricane Hazel in 1954

• Revegetation program studies initiated in March 1961 by Woodhouse and Hanes funded by a grant from the Cape Hatteras National Seashore

NC dune plant history….

• Funding to support studies expanded in 1962 with funds from NC Dept. of Water Resources, and funds from state appropriations in 1963

• In 1963, NCSU & NC Forestry Division, seek to develop a supply of commercially available planting stock

NC dune plant history…

• January 1966 Woodhouse and Hanes publish Dune Stabilization with Vegetation on The Outer Banks of North Carolina.

• “…four grasses growing on the Banks which appear to show real promise…”– American beachgrass

– Sea oats

– Bitter panicum

– Saltmeadow cordgrass

American beachgrass

• Planted extensively by the Civilian Conservation Corps on the Outer Banks from 1934 to 1936– Planting stock secured by digging and dividing

native plants– Commercially available in NC since 1963

• A selection by the SCS from Lewes, Delaware started NC production

American beachgrass

• Ammophila breviligulata• Native north of Cape

Hatteras• Cool season perennial• Easy to multiply

vegetatively• Easy to harvest, store,

and transplant

American beachgrass - Advantages

• Low cost

• Readily available

• Often specified by USACE

• Winter planting season

• Good sand trapper and stabilizer

• Adapted to pioneer zone conditions

American beachgrass - Disadvantages

• Not recognized by CAMA as “stable natural vegetation” in SE NC

• Affected by heat and drought – often thins out and replaced by better adapted species

• Susceptible to a soft scale, Eriococcus carolinae• Susceptible to a fungus pest, Marasmius blight• Does not persist when sand and nutrient supply

cut off

Preference for American beachgrass?

• “For large scale dune plantings in North Carolina, American beachgrass has the practical advantage over other species due to its commercial availability, relatively low cost, ease of transplanting and quick establishment”.

• UNC Sea Grant College Publication UNC-SG-82-05. Building and Stabilizing Coastal Dunes with Vegetation. Broome, Seneca, and Woodhouse. 1982.

Why Not Sea Oats?

Why not Sea Oats?

• Difficult to propagate• “As recently as 10 years ago, reputable scientists

were saying that this species did not produce viable seeds.” - Woodhouse & Hanes, 1966.

• 1964 – seedlings produced in NC, but with difficulty

• Transplanting recommended from existing stands

Sea Oats

• Uniola paniculata• Native range from the Virginia Capes

southward into Mexico• Warm season perennial• Hummocky dunes?

– “…where good stands have been observed, there seems to be little difference between a sea oat dune and a beachgrass dune.”

Sea Oats - Advantages

• Native, well adapted to pioneer zone• CAMA recognizes for setbacks• Excellent sand trapper and stabilizer• Aesthetically pleasing• Wildlife food and habitat• Custom grown for local areas• Renewable resource• Long-lived• Spring and summer planting season

Sea Oats - Disadvantages

• Cost compared to American beachgrass– Survivability– True cost comparison

Commercial Sea Oat Production in North Carolina

• Studies initiated in 1996 with 2 goals:– Grow sea oats in NC from NC seed for NC

beaches– Establish commercial production in NC

• Visits to Florida growers in 1997– Not willing to share details– “you guys did all the work”

Commercial Sea Oat Production in North Carolina

• Successful production in float system in the winter of 1998

• Summer 1998 proposal to Town of Long Beach (Oak Island)

• 2000 – 120,000 seedlings grown and transplanted to dunes

• 2000 - commercial grower established in Brunswick County

Oak Island Sea Turtle Habitat Restoration Project

• USACE specifies:– 133,500 American beachgrass– 10,383 sea oats– 5,933 bitter panicum

• Plan modified to replace all American beachgrass with sea oats grown from seeds harvested on Oak Island

More Plants for the Pioneer Zone

• Bitter panicum (Panicum amarulum)

• Saltmeadow cordgrass (Spartina patens)

• Seashore elder (Iva imbricata)

Choice of Species

• “It is an accepted concept of ecology that species diversity lends stability to a system.” – Broome, Seneca, Woodhouse. 1982.

• Practical Considerations– Plant availability– timing