With Hurricane Irma on track to slam into Florida this weekend or early next week, more and more units of the National Park System were closing in preparation.

The two of us recently spent a sunny spring day on Cumberland Island, Georgia’s largest and southernmost barrier island. Ninety percent of the 30,000-acre island is owned and managed by the National Park Service as a national seashore. This was our fourth visit to the island, but it had been a number of years since we last walked the beach and marveled at the beautiful live oak trees. Early spring is a good time to visit the national seashore that can become uncomfortably hot during the summer months.

Hurricane Matthew was expected to strengthen into a category 4 hurricane by the time it reaches Florida, leading many units of the National Park System from Florida into North Carolina to batten down for the storm.

You can find them at Cape Cod National Seashore, Fire Island National Seashore, Assateague Island National Seashore, Cape Hatteras National Seashore, Cape Lookout National Seashore, and Cumberland Island National Seashore. But what exactly is a maritime forest and how to they survive in these salty environments?