Located where the headwaters of four major Michigan river systems meet this undulating topography was formed by the retreating of two glacial lobes some 10,000 years ago, hence this is known as the interlobate region. They left piles of glacial till in their wake and formed hills and ridges known as kames, eskers, and moraines. Over the next few millennium the climate slowly warmed and dried until about 5,ooo years ago when it stabilized into a dynamic system known as Oak Savanna and continued on in various manifestations of that habitat until European agriculture came to dominate and destroy the processes that kept oak savanna alive. Blue Jays had probably planted the first Oaks and Indigenous tribes kept the savanna open through intentional burning of the land. A fact reminding us that natural history and human history are intimately connected.
This area could be named for all of its bodies of water as easily as its hills. Also formed by glacial activity this vast system of lakes, streams, and wetlands (including fens, swamps, marshes, bogs) filled the earth like a scene out of the book of Genesis. The old Lake Maumee just to the east slowly drained forming present day lake Erie. The flood plains of the River Raisin became rich habitat for many species. The delta where the Raisin meets Erie became abundant with all manner of life from wild rice and american lotus, to a diverse array of waterfowl, amphibians, fish, and wild creatures innumerable. The hills to the west are the fertile origin of this verdant environment, and even today, after southeast Michigan has been industrialized and ecologically reduced, the Iron Creek sub basin of the River Raisin watershed remains a hot spot of biodiversity.
We are near the edge of ecological zones both in latitude and longitude. This landscape could be seen as an ecosystem cross roads of sorts, as parts of the southern hardwood forests mix with the northern hardwoods. While at the same time the eastern edge of the tall grass prairie/oak savanna complex meets with the forests that extend from here to the Atlantic Coast. For example the traditional range of the native American Chestnut was primarily to the east of here and stopped in Southeast Michigan. There is one on the Kellwood property that has a single living branch. It never got the blight, and perhaps is the western most old growth chestnut in the country. The Tamarack reaches its southern limits here, and the Shellbark hickory its northern. Many prairie flowers find their eastern limits here.
Our climate is influenced to some extent by being on a peninsula in the Great Lakes, but less so then Michigan’s coastal areas. We tend to be slightly drier, warmer, and sunnier than the rest of Michigan.
Written by Jeremy Siegrist