Bixby State Preserve is a

nature reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, funga, or features of geologic ...

located in southwestern

Clayton County, Iowa Clayton County is a County (United States), county located in the U.S. state of Iowa. As of the 2020 United States census, 2020 census, the population was 17,043. Its county seat is Elkader, Iowa, Elkader. The county was established in 1837 and ...

, in the

midwestern United States The Midwestern United States (also referred to as the Midwest, the Heartland or the American Midwest) is one of the four census regions defined by the United States Census Bureau. It occupies the northern central part of the United States. It ...

. It is located north of Edgewood. It is operated by the Iowa Department of Natural Resources as one of the Iowa state preserves. Bixby State Preserve is one of the few places in the world to contain algific talus slopes and consequently has an ecosystem encountered in only a few other sites, all in the

Driftless Area The Driftless Area, also known as Bluff Country and the Paleozoic Plateau, is a topographic and cultural region in the Midwestern United States that comprises southwestern Wisconsin, southeastern Minnesota, northeastern Iowa, and the extreme ...

. They are mainly elsewhere in Iowa, but also in southeastern

Minnesota Minnesota ( ) is a U.S. state, state in the Upper Midwestern region of the United States. It is bordered by the Canadian provinces of Manitoba and Ontario to the north and east and by the U.S. states of Wisconsin to the east, Iowa to the so ...

, southwestern

Wisconsin Wisconsin ( ) is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michig ...

and northwestern

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

. In winter and early spring comparatively warm air rises from the elaborate system of

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water ...

s, causing cold moist air to be drawn into the north-facing talus slopes and sent through fissures into ice caves, where it turns to ice on the walls of the cave. In summer and fall, the system is reversed, with cool moist air venting to the talus slopes, creating a unique ecosystem. The only road into the preserve is closed on both the north and south sides of the preserve as of June 7, 2013. The south entrance is open during the summer. Trout fishing is allowed.

Sources

Bowling Green State University: Bixby State Preserve

External links

U.S. Geological Survey Map
at the U.S. Geological Survey Map Website. Retrieved December 6, 2022. Iowa state preserves Algific talus slopes Caves of Iowa Driftless Area Ice caves Protected areas of Clayton County, Iowa Landforms of Clayton County, Iowa {{US-cave-stub