What is the Atlantic Coastal Plain?
The Atlantic coastal plain is a relatively flat area of land stretching from Long Island, south into northern Florida. The hilly piedmont forms the western boundary, while the Atlantic Ocean creates a border in the east.
Located in a sub-tropical region, summers usually start early, are long, hot, and humid, while winters can be changeable, with cold artic air occasionally being replaced by warmer weather from the south. Precipitation averages around 53 inches (135cm) and falls throughout the year, though periods of drought are not uncommon. The Atlantic coastal plain is situated between USDA hardiness zones 7 and 9.
Weather statistics at Willard in Pender County, NC - USDA hardiness zone 8a:
- Lowest temperature: 0°F (-18°C)
- Average minimum temperature: 10 to 15°F (-9 to -12°C)
- Average maximum temperature: 90°F (32°C)
- Highest temperature: 105°F (40°C)
- Average precipitation: 53in. (135cm)
- Average yearly snowfall: 3in. (7.5cm)
- Record snowfall: 12in. (30cm)
- Average first frost: October 25
- Average last frost: April 10
Many plant communities occur within the Atlantic coastal plain, making it one of the most biologically rich areas in North America. Swamps, bottomland forests and other wetlands are common, and form valuable habitat for wildlife. Longleaf pinelands and savannas once dominated large areas, but most have now been converted to agriculture and forestry plantations. At the coast, dunes and maritime forests help protect the barrier islands from storms, while estuaries provide important breeding grounds for marine and bird life.
The Atlantic coastal plain is home to over 2000 plant species. While many of these plants can found growing in other regions of eastern North America, some like the Venus Fly Trap (Dionaea muscipula) and the Spring Flowering Goldenrod (Solidago verna) are unique and can be found nowhere else.
Many coastal plain soils are formed from marine sediments, laid down when the sea once covered the region. Sediment eroded from the Appalachian Mountains, and peat soils formed by vegetation decaying over thousands years, also cover large areas. Diverse soil types and hydrology’s allow many plant communities to flourish.
Threats to the ecology of the Atlantic coastal plain include habitat loss, due to human development. The suppression of fire, needed to maintain the viability of certain plant communities, and the spread of exotic invasive plants and plant diseases are becoming major concerns.