These deepwater swamps have surface water throughout all or most of the growing season but water levels vary seasonally and annually. Moving laterally within this area, along the banks of the present day channels of the Middle and Tensaw Rivers, bald cypress and tupelo dominate the species which are common along the open water river corridors. They transition into the river swamp forest, or deepwater alluvial swamp, which naturally supports bald cypress and water tupelo in equal numbers. Common shrubs include common alder, buttonbush, swamp privet, fetterbush, and black willow. Typical herbs include golden club, swamp lily, and fragrant water lilies.
Spanish moss is a common epiphyte growing among the crowns of trees.
These habitats can easily be seen from the I-65 bridge that dissects the Delta north of Mobile. Moving further laterally from the river channels, oak dominated bottomland hardwood forests occur in areas where temporary flooding is common. The lower hardwood swamp forest, sometimes referred to as the first bottom, is characterized by a greater diversity of woody species. These include overcup and laurel oak, water hickory, river birch, red maple, and green ash, as well as cottonwood in disturbed areas. Non-woody plants include lizard s tail, jewelweed, and several species of ferns.