Field Guide: Dune Plants of Bald Head Island
By Hannah Miu, Conservation Intern (Fall 2023)
If you were to ask someone to imagine the beaches of Bald Head Island, odds are they would picture ocean waves breaking over the shoals, gulls and willets darting in and out of the water, and miles of long, grassy sand dunes.
Dunes are a key fixture of beaches and coastal ecosystems. Sand dunes absorb and dissipate wave and tidal energy, making them important natural barriers against storm surges and coastal erosion. Grasses and shrubs on the dunes stabilize the sand, creating habitat for birds, small mammals, and insects. While dunes prevent coastal erosion, they themselves are fragile ecosystems and are prone to erosion and compaction. Treading on dunes can destabilize the sand and cause damage to and uproot plants. The weight of footsteps can also compact loose sand, making it harder for the dune plants to grow. To keep these processes in place, beach-goers are advised to stay away from walking on sand dunes.
Although we cannot walk directly on the dunes, there are plenty of boardwalks and beach accesses across Bald Head Island that allow us to safely reach the beach from the road. These boardwalks are a great opportunity to appreciate both the dunes and the plants that keep them there. The following is a guide to help you identify plants as you walk along the boardwalk to and from the beach.
One of the most prominent dune plants on Bald Head Island are Sea Oats. These plants can be found on beach fronts and barrier islands along the U.S. eastern seaboard due to their massive root system that allows them to stabilize the dunes. The sand gets caught in the brown, oat-like structure at the top of the plants and falls down, growing the dune.
Largeleaf Pennywort (Hydrocotyle bonariensis)
This plant produces a large, rounded leaf at the ends of its long stems. It spreads by sending out runners, or slender stems growing horizontally along the ground. The lily-pad-like leaves are a good indicator of Pennywort.
Camphorweed is a flowering plant that grows in coastal dunes, grasslands, and pinelands. They’re native to the southeast U.S. and can be found as far south as Mexico and Belize.
Blanket Flower (Gaillardia pulchella)
These flowers are prolific on barrier islands and like to grow in the soft sand lining beach walkways; they have enlarged, tubular flowers that are red with yellow edges.
Seaside Sandmat (Euphorbia polygonifolia)
This plant is an annual herb native to both the U.S. east coast and the Great Lakes region. It grows horizontally and has a red stem.
Earleaf Greenbrier (Smilax auriculata)
Another name for this perennial vine is wild-bamboo, although it is not closely related to bamboo. It grows in sun-lit locations in low elevation sandy woodlands.
Seaside Oxeye (Borrichia frutescens)
Seaside Oxeye goes by many names, including sea-oxeye daisy, sea marigold, seaside tansy, and beach carnation. It grows as a small to medium size shrub with daisy-like flowers.
Beach Croton is a dense, herbaceous plant that has broad leaves with a notable silvery appearance.
Originally, Vitex was planted as a dune erosion control measure due to its sprawling roots, but its rapid growth has made it an invasive dune species. The plant grew to form large monocultures and beat out native dune species; its coverage is so thick it even hinders sea turtles from laying eggs. The woody shrub grows short and thick with long runners and purple flowers.
The Bald Head Island Conservancy has been contracted since 2005 by the Village of Bald Head Island to identify and eradicate Beach Vitex. More information can be found here: https://bhic.org/conservation/bald-head-island-dune-health/#:~:text=Beach%20Vitex%20(Vitex%20rotundifolia)%2C,animals%20on%20Bald%20Head%2
