Bismarck Conservation Area is a 1,188-acre tract of land in St. Francois, Iron, and Washington counties. The area surrounds 210-acre DiSalvo Lake, which was constructed in 1944 by the Hanna Mining Co. to serve as a water reservoir for nearby lead mining operations. The Department of Conservation purchased the property from Hanna in 1981.
In addition to its upland forested areas, Bismarck features an igneous glade and savanna complex, which is currently being restored, and 50 acres of wet-mesic bottomland forest. The glades and savannas support little bluestem grass, post oak, blackjack oak, fragrant sumac, pineweed, and prickly pear cactus.
The wet-mesic bottomland forest is one of the best such examples in the St. Francois Mountain region. It supports the rare oval ladies' tresses orchid, has an understory of pawpaw, spicebush and musclewood and a canopy dominated by pin oak and swamp white oak. A large stand of witch hazel grows near the dam of the lake.
The geology of Bismarck Conservation Area is among the oldest in Missouri; it includes Precambrian igneous rock and lava-formed Cambrian-age LaMotte sandstone and Cambrian-age dolomites.
DiSalvo Lake, which serves as the headwaters of the St. Francis River, contains good numbers of bass, bluegill, channel catfish, and crappies. The Department provides a boat ramp, parking areas, and disabled accessible facilities, including a fishing dock.
Hunting is available for deer, turkey, squirrel, rabbit and waterfowl.