The Thumb Land Conservancy owns three preserves in St. Clair County:

• Dead End Woods Sanctuary - 17.6 acres in Fort Gratiot Township
• Gerrits Sanctuary - 38.5 acres in Ira Township
• Peltier Beach Ridge Sanctuary - 11.5 Acres in Fort Gratiot Township

Since 2011, the Thumb Land Conservancy has been under contract with the Saint Clair County Drain Commissioner, Saint Clair County Road Commission, and Pro-Tel Development to monitor and steward a 51-acre preserve along the east side of Michigan Road, north of Dove Road and south of the Canadian National Railway tracks in Port Huron Township. The preserve is just a small part of a large remnant of northern forest complex characteristic of the Port Huron area, an extensive lakeplain wetland crossed by upland sand ridges left by higher waters of the early Great Lakes. The land was preserved as wetland mitigation for two separate projects permitted by the Michigan Department of Environmental Quality. Ownership of the land was then transferred to the SCCDC. As a condition of the two permits, the MDEQ required monitoring and stewardship of both parcels for 5 years by a third party conservation organization.

Michigan Road Preserve Map

Complex of wetland and tip-up mounds on the preserve. This is Painted Trillium habitat.

Up on one of the sand ridges on the preserve.

Down in the shrub swamp with Tag Alder, Black Chokeberry, and Royal Fern.

The Michigan Road preserve is a valuable piece of the Port Huron area’s natural history. It’s a fascinating complex of forested swamp and upland sand ridges bordering an almost impenetrable shrub swamp. The forest is largely a second-growth northern community composed of northern species like Red Maple, Paper Birch, Black Ash, Blueberry, Wintergreen, Bunchberry, Bracken Fern, Wild Sarsaparilla, Starflower, and Canada Mayflower. Michigan Endangered Painted Trillium is known from nearby locations with similar northern forest habitat and is likely on the preserve. Interior portions of the preserve are covered by northern shrub swamp dominated by dense thickets of Tag Alder, Black Chokeberry, and Nannyberry, mixed with invasive Glossy Buckthorn and Common Reed. Marsh Saint John’s-wort, an uncommon northern species, has also been found in the shrub swamp. While these species occur throughout Michigan, their distribution is generally concentrated north of Michigan’s Transition Zone, the broad division between northern and southern flora in Michigan running roughly from Muskegon east to the Saginaw Bay and across the Thumb. The northern plant community on the preserve is somewhat disjunct from its usual location north of the Transition Zone, but this is characteristic of the flora in the Port Huron area, influenced by the cooler growing season and extensive sand soils near Lake Huron. Historic fire disturbance may also have been another important factor in maintaining the northern flora.

A further unique aspect of the vegetation on the preserve is the occurrence of southern species, especially on the sand ridges, that enhance the vegetative diversity and create a blend of northern and southern flora unique to Saint Clair County. Distinctly southern species on the preserve include Black Oak and Pin Oak hybrids, Black Gum, Sassafras, Juneberry, and Smooth Highbush Blueberry. This north-south quality of the area’s vegetation was described about 100 years ago by noted Port Huron botanist Charles K. Dodge.

Eastern White Pine and Paper Birch on the Michigan Road preserve. It looks like "up North".

And then there are big ole Sassafras trees. It looks like "down South".