North Carolinan Coastal Sand Dunes

Phytogeographically this dune zone extends from Cape Lookout in the south to Chesapeake Bay (Cape Henry) in the North. All dune systems appear to be acidic and the following dune zones have been described (Doing 1981).

Strandline
These are well developed on some beaches. The main annual species include Cakile edentula, Euphorbia polygonifolia and Salsola kali, while typical perennial species are the grasses Panicum amarum and Panicum amarulum.

Embryonic Dunes
These occur as a low foredune ridges up to 2 m high. Most of the vegetation appears to be monospecific and grass dominated. In the south the main species is Uniola paniculata but towards the north (near Virginia Beach) this is replaced by Ammophila breviligulata.

Foredune
In this zone the foredune ridge is naturally low and frequently disrupted by the strong onshore winds and occasional hurricanes. Uniola paniculata is the main sand binding species but it is not as effective as Ammophila breviligulata. For this reason Ammophila breviligulata often planted in to regions south of its natural distribution.

Sheltered regions within the foredune zone
This is relatively narrow zone (less than 50 m) but provides habitat for several species including Hydrocotyle bonariensis, Oenothera humifusa and Strophostyles helvola (Fabaceae).

Pioneer Dune Scrub
The main species here are the two evergreen shrubs Myrica cerifera and Ilex vomitoria. The former is able to fix nitrogen.

Blowouts
Small blowouts are frequent and mainly colonised by the bunch grass Andropogon scoparius. These have been described as steppe-like communities.

Short dune grasslands
These do not appear to be a major feature and no calcareous dune grasslands are present.

References

Doing, H. 1981. A comparative scheme of dry coastal sand dune habitat, with examples from the eastern United States and some other temperate regions. Veroff. Geobot. Inst. Rubel, 77: 41-72.