I should clarify that the article
focuses on the distribution of habitat in the eastern Thumb with which I am more
familiar, although I've spent a lot of time up there too, partly to track an
isolated population of Pitcher's-thistle. There is similar habitat along the
Saginaw Bay side of the Thumb up to the tip at Port Austin (Sebewaing to Port
Crescent State Park), but my understanding is that these are more wind-formed
dunes than water-deposited beaches. If Denny Albert or Mike Penskar are out
there, they may wish to chime in. The main point of my article though, is that
the habitat should receive more attention on the east side of the Thumb because
it is there, it is degraded but intact, and there is still enough to create a
larger coastal preserve.
Huron Ecologic, LLC
Rochester Hills, Michigan 48309 USA
phone & fax: 248-852-4682
Huron Ecologic provides wetland
delineations, wetland permitting, wetland mitigation design & monitoring,
tree inventories, botanical & ecological surveys, natural area protection,
nature education, and technical training.
Here is a web site with an article I wrote
about glacial beach ridge and swale habitat of the Thumb in the Lakeshore
"Those living near Lake Huron, especially in Saint Clair
County, are probably familiar with the large ridges of sand that parallel
the lakeshore, some over a mile inland. Unlike wind-formed sand dunes along
Lake Michigan, these ridges are actually old beaches, deposited by ancient
waves thousands of years ago. Known as glacial beach ridges and swales, the
swales being the lower areas between the ridges, this landscape formed along
the Thumb shoreline roughly 4,500 years ago, about the same time the great
pyramids of Egypt were constructed."
I'm aware that there are older
beaches inland, but from my experience and understanding, these are
primarily individual ridges, similar to sand ridges along glacial
drainageways, lacking the characteristic ridge and swale pattern that occurs
along the shoreline. This landscape is described in greater detail in the
"Wooded dune and swale complex" community abstract available on
the Michigan Natural Features Inventory web site.
While much of the habitat in
the lower Thumb may not be considered as well developed as that in other
counties, some of it is. In my opinion, it warrants more attention, and
certainly much better treatment than it has received left to the hands of
most wetland consultants plying their trade in the booming commercial
expansion north of Port Huron in the 90's.