Astonishing biodiversity exists in Congaree National Park, the largest intact expanse of old growth bottomland hardwood forest remaining in the southeastern United States.  Waters from the Congaree and Wateree Rivers sweep through the floodplain, carrying nutrients and sediments that nourish and rejuvenate this ecosystem and support the growth of national and state champion trees. Prehistoric foragers hunted the area and fished its waters. The Congaree Indians claimed the floodplain and Spanish explorer Hernando de Soto recounted the intrigue of the area in his journals. Around 1700, the Congarees were decimated by a smallpox epidemic introduced with the arrival of European settlers. The new residents obtained land grants from the King of England until 1776 when the state of South Carolina assumed the right to distribute ownership of the land. Attempts to make the land suitable for planting, as well as grazing, continued through 1860. The floodplain's minor changes in elevation and consequent flooding stifled agricultural activity; but the intermittent flooding allowed for soil nutrient renewal and enabled the area's trees to thrive. Bald Cypress, in particular, became a target for logging. By 1905, the Santee River Cypress Lumber Company, owned by Francis Beidler, had acquired much of the land. Poor accessibility by land confined logging to tracts near waterways so that logs could be floated down river. In the perpetual dampness, though, many of the cut trees remained too green to float. Operations were suspended within ten years, leaving the floodplain basically untouched.