The Interior Low Plateau has an abundance of sinkhole ponds in the karst regions of the Mitchell Plain, Pennyroyal Plain, and Highland Rim.
These isolated communities were historically found within a matrix of wet prairie.
These communities are often covered in swamp forest, and are dominated by swamp cottonwood (Populus heterophylla) and red maple (Acer rubrum).
High-quality herbaceous examples have species with coastal plain affinities.
Many of these communities have been destroyed due to drainage for agriculture.

Emergent shrub sloughs are found along the bottoms of major rivers, such as the Cumberland River and Tennessee River.
These are dominated by buttonbush (Cephalanthus occidentalis), and along the Tennessee River contain bald-cypress (Taxodium distichum).
These sloughs were historically widespread, but dam construction and agricultural activity have destroyed most of them.

A rare wetland type in this region is the calcareous seepage fen.
These are found sparingly in the Highland Rim, and are dominated by grass of Parnassus (Parnassia grandifolia) and contain the federally-endangered Tennessee yellow-eyed grass (Xyris tennesseensis).
Calcareous seeps are also found near glades in the Inner Nashville Basin.
These communities often have extensive stands of sunnybells (Schoenolirion croceum) and other rare species.
Calcareous seeps and swamp forest are also found sparingly in the Bluegrass region.
These contain trees such as green ash (Fraxinus pennsylvanica) and swamp white oak (Quercus bicolor), along with many herbaceous plants that are considered regionally rare.
The Interior Low Plateau has an abundance of sinkhole ponds in the karst regions of the Mitchell Plain, Pennyroyal Plain, and Highland Rim. These isolated communities were historically found within a matrix of wet prairie. These communities are often covered in swamp forest, and are dominated by swamp cottonwood (Populus heterophylla) and red maple (Acer rubrum). High-quality herbaceous examples have species with coastal plain affinities. Many of these communities have been destroyed due to drainage for agriculture.
Emergent shrub sloughs are found along the bottoms of major rivers, such as the Cumberland River and Tennessee River. These are dominated by buttonbush (Cephalanthus occidentalis), and along the Tennessee River contain bald-cypress (Taxodium distichum). These sloughs were historically widespread, but dam construction and agricultural activity have destroyed most of them.
A rare wetland type in this region is the calcareous seepage fen. These are found sparingly in the Highland Rim, and are dominated by grass of Parnassus (Parnassia grandifolia) and contain the federally-endangered Tennessee yellow-eyed grass (Xyris tennesseensis). Calcareous seeps are also found near glades in the Inner Nashville Basin. These communities often have extensive stands of sunnybells (Schoenolirion croceum) and other rare species. Calcareous seeps and swamp forest are also found sparingly in the Bluegrass region. These contain trees such as green ash (Fraxinus pennsylvanica) and swamp white oak (Quercus bicolor), along with many herbaceous plants that are considered regionally rare.
Interior Low Plateaus