Talk by Southeast Michigan Land Conservancy president Jack R. Smiley about the ongoing efforts to save this unique habitat from development. Sibley Prairie is a 440-acre remnant of a globally rare lakeplain prairie ecosystem south of the Detroit airport. 6–7:30 p.m., U-M Matthaei Botanical Gardens, 1800 N. Dixboro Rd. Free, metered parking. annarbor.wildones.org.