The 1,210-acre Maxton Plains Preserve, located on Drummond Island in northern Lake Huron, contains a unique and diverse assemblage of natural communities, including alvar, rich conifer swamp, boreal forest, bedrock beach and Great Lakes marsh. The rich conifer swamps are dominated by white cedar. The boreal forest is composed primarily of balsam fir, white spruce, and aspen. Young aspen forests border many of the open alvars. The shoreline areas contain stretches of bedrock beach with scattered strips and pockets of Great Lakes marshes. The Great Lakes marsh at Grand Marais Lake is an exceptionally high quality marsh.
Alvar is a Swedish term used to describe dry grasslands found on limestone pavements. The last glacier receded over 10,000 years ago, leaving no, or only a very thin (up to 10 inches), soil layer over limestone bedrock. Topography of alvar is flat and horizontal plates of bedrock are sometimes exposed-giving the impression of, and earning the name, “pavement” or “limestone pavement.” Areas of pavement alvar are found in central Maxton. On the pavement alvars, the plants grow only in the bedrock joints where soil and sediment collect.
This habitat contains an extremely rich diversity of flora and fauna and hosts a unique mixture of arctic tundra and Great Plains prairie plant species. Eight Michigan state rare plants grow in the alvars. Among these are the prairie smoke, a spring bloomer, and Houghton’s goldenrod, which bloom just as the prairie grasses turn gold in the late summer sun. Little bluestem grass and prairie dropseed grass also thrive in the sparse soil. This site attracts an array of birds, including such rare and threatened species as the upland sandpiper, osprey, northern harrier, sharp-tailed grouse and as many as 160 other species of birds.
Why TNC Selected This Site
The Maxton Plains Preserve protects the globally significant alvar landscape and ten Michigan state-rare plants, eight found in the alvars and two found in the forests. The alvars found on Drummond Island are the largest remaining high quality alvars in North America. This project will also protect important shoreline communities associated with the alvar landscape, including Great Lakes marsh at Grand Marais Lake and bedrock beaches on the north shore near Poe Point and the south shore at Potagannising Bay. The Maxton Plains Preserve protects nesting and feeding habitat for the state-threatened osprey and potentially for grassland, forest, and shore birds.
What TNC Has Done/Is Doing
The first purchase of 140 acres at Maxton Plains was completed in 1984. Since then land has been acquired in 1986, 1993, 1996, 1998 and 2001 which have expanded the preserve to its current size of 1,210 acres. Because alvar is such a rare and unique natural community, most of our efforts on this preserve are concentrated on threats such as invasive species and incompatible recreational use. We have been actively involved on Drummond Island through participation in planning groups such as the Drummond Island Trail Working Group which established officially designated ORV trails while protecting sensitive areas. In 2010 & 2011, we partnered with the Michigan Department of Natural Resources to reduce the threat of non-native invasive plants such as Spotted Knapweed and Leafy Spurge on the Maxton Plains alvars.