The Maple River has long been a site of research and teaching for classes at UMBS. It is home to a federally-listed water beetle (Brychius hungerfordii), has been the site on which numerous dissertations and theses, as well as UMBS class projects, have been carried out, and with the removal of the former dam site, continues to be a focal point for aquatic research in the region. It is also a favorite fish spot for trout fishermen. We will create an illustrated flora on the diatoms of the Maple River. It will be based on material collected intermittently over the last 40 years from the East Branch of the Maple River and the confluence of both East and West branches at former Lake Kathleen and the flow past the former dam site and from there to Burt Lake. We have a cumulative list of taxa from the East Branch and downstream from the dam site and most of our work will involve documenting taxa with light microscopy as well as writing keys and descriptions for these taxa. We will also undertake a collecting trip along the West Branch of the Maple River to complement our extensive collections from other sites along the Maple River. We will process these samples and begin documenting species from them as well. The result of our work will be an illustrated guide to the diatoms of the Maple River, that will support future research and teaching at UMBS and beyond.