Piedmont National Wildlife Refuge is a 35,000-acre (140 km²) National Wildlife Refuge established in 1939 and located in central Georgia. It is primarily an upland forest dominated by loblolly pine on the ridges with hardwoods found along the creek bottoms and in scattered upland coves. Clear streams and beaver ponds provide ideal wetland habitat for wood ducks and other wetland dependent species. In the early 19th century the European settlers arrived in abundance and began to clear the land to plant a variety of crops. The settlers removed more than 90% of the forest. The continuous planting of cotton caused serious erosion and soil infertility.