Hoosier Prairie began in the 1970s as wasteland that conservation organization found of a unique interest. From a core of 304 acres (123 ha), it has grown to 1,547 acres (626 ha) of important prairie habitat. The area was designated a National Natural Landmark in 1974 and a State Nature Preserve in 1977 The sandy soil creates a variety of habitats, from oak barrens, wet prairie, including sedge meadows and prairie marshes. More than 350 native species of vascular plants have been identified. A minimum of 43 species are uncommon in the State of Indiana. It is a unit of the Indiana Dunes National Lakeshore.