Vegetation Monitoring at Cape Lookout National Seashore: 2022 Baseline

Plant communities shape how ecosystems work, shelter and feed wildlife, and are often the first thing that draws people to the outdoors. Tracking how they change, and what stresses them, is key to understanding the health of park lands. In 2022 the National Park Service's Southeast Coast Network (SECN) began long-term vegetation monitoring at Cape Lookout National Seashore in North Carolina, establishing a baseline for future comparison.

Vegetation plots established in May and June 2022 at Cape Lookout National Seashore. National Park Service

The seashore

Cape Lookout National Seashore covers about 11,430 hectares (28,243 acres) along 91 kilometers (56.5 miles) of Atlantic coast in eastern North Carolina, from Pamlico Sound and Ocracoke Inlet to Beaufort Inlet. It consists of three barrier islands — North Core Banks, South Core Banks and Shackleford Banks — separated from the mainland by Core and Back Sounds. Its vegetation runs from open beach and dune grasslands on the ocean side to tidal marshes on the sound side, with swales between the dunes, backdunes and enclosed wetlands in between.

How the monitoring works

The network uses a peer-reviewed protocol, similar to that of other NPS Inventory and Monitoring networks in the East and modeled on the Carolina Vegetation Survey. Permanent plots, placed at random within broad habitat types, record:

1. the richness and abundance of all native and non-native vascular plants;
2. the basal area, density and health of woody species;
3. the density of fuels on the forest floor;
4. disturbances such as insect pests and disease; and
5. physical conditions such as landform, soil nutrients and canopy cover and height.

In May and June 2022, 49 plots were established across four areas — North Core Banks, South Core Banks, Cape Lookout and Shackleford Banks — in four habitats: maritime open uplands, maritime upland forests and shrublands, maritime nontidal wetlands and maritime tidal wetlands.

Site conditions

Soils ranged from acidic to slightly alkaline (pH 4.5 to 8.7), and ridges and swales marked both young and old dune systems. The seashore has always been shaped by wind, tides and waves. Human disturbances seen in other network parks, such as past plowing, altered fire regimes and changed hydrology, were not found in these plots. On Shackleford Banks, however, stunted plants in several plots were likely caused by grazing feral horses; whether grazing has changed vegetation across the island is not yet clear.

Average species richness by plant growth form in Cape Lookout's habitats. National Park Service

What grows there

• 186 plant species were recorded, including 11 not found in earlier surveys and 15 listed as rare by the North Carolina Natural Heritage Program, among them the state-threatened blue witchgrass (Dichanthelium caerulescens). Rare species appeared in every habitat, most often in nontidal wetlands and upland forests.
• Native richness per plot ranged from 4 to 48 species, highest in the upland forests and shrublands of Shackleford Banks. Grass-like and other herbaceous plants dominated the wetlands.
• Non-native species were uncommon, and none appeared in tidal wetlands. Two top-ranked invasive plants were found: Japanese honeysuckle (Lonicera japonica) and common reed (Phragmites australis).
• Sand live oak (Quercus geminata), a close relative of the common live oak not previously reported on North Carolina's Outer Banks, shared the canopy in one Shackleford Banks plot.
• Shore little bluestem (Schizachyrium littorale), rare in North Carolina, grew in dune plots on North Core Banks and the Cape Lookout area but not on Shackleford Banks, where horses grazed both open uplands and nontidal wetlands.

Native versus non-native species by habitat. National Park Service

All plots are scheduled to be sampled again in spring or summer 2026.

About the network

The National Park Service began its Vital Signs Monitoring program in 1999 to track the condition of more than 270 park units with significant natural resources. The Southeast Coast Network includes twenty park units across North Carolina, South Carolina, Georgia, Alabama and Florida, from national seashores to military parks.

Sources

• National Park Service, Southeast Coast Network, "Terrestrial Vegetation Monitoring 2022 Data Summary for Cape Lookout National Seashore": https://www.nps.gov/articles/000/secn-vegetation-monitoring-calo-2022.htm