Wednesday, July 04, 2007

Extra-Urban Expeditions: Ohio’s Floating Island


P6230009.JPG, originally uploaded by ZephyrusNYC.

Occasionally Hominy Grits ventures outside the great metropolis to see what’s ticking in other parts of the world. The latest such adventure occurred a few weekends ago when yours truly ventured all the way out to the heartland (Ohio, to be exact) to experience a truly unusual place: the Cranberry Bog State Nature Preserve, at Buckeye Lake, in Licking County.

I grew up barely an hour away from Buckeye Lake, and even visited it once while in high school. But I never realized what an interesting spot it is. Both the human history of the lake and its natural history are remarkable.

There are very few natural, open-water lakes in Ohio (with the exception of Lake Erie, if that counts). The lakes found there today are nearly all man-made. Buckeye Lake is no exception. I remember it as a somewhat bucolic, longish lake with old vacation cottages, fishermen and waterskiiers. I figured that like many of the state’s recreational lakes, it was the product of early or mid-twentieth century engineering.

Imagine my surprise to discover that it was in fact created way back in 1830 to supply water for the brand new Ohio and Erie Canal. The lake proved too shallow to be able to adequately supply water to the canal system, but managed to live on as a park and recreational area.

The creation of the lake occasioned the creation of a truly bizarre and unique natural formation: a cranberry bog on an island – a floating island, no less – near the present north shore of the lake.

Our trek to this curiosity began very early on a Saturday morning, around 7:00 a.m. to be exact, in the hopes of getting on a tour of the bog. Having failed to get the required and coveted reservations, we put our party of five on the standby list. As luck would have it, our entire party was on a boat in a matter of minutes. Being there early provided another advantage – beating the summer heat.

We arrived at our destination after a very short boat ride. The island bog is not far from shore. While this island “floats,” it doesn’t move about, because the sphagnum moss that forms its foundation is still attached to the bottom of the lake. Think of this moss mat as a sort of giant sponge that swelled up back in 1830 when the lake was created, pushing the surface above the water level of the lake.

Pieces of the mat can and do break loose from time to time. Once, a few years back, a man awoke one morning to find his lakefront picture window blocked by trees and shrubbery that were not there the night before! Some of the island had come unmoored in the night, trees and all, and floated right across the lake.

















Upon disembarking on the moss mat-island, practically the first thing we encountered was a tremendous thicket of poison sumac! I had never seen poison sumac before. One is not likely to encounter it, unless he or she is in the habit of hanging out in swamps and such. My aunt, an accomplished naturalist, declared that she had never seen so much of it in one place. The poisonous shrub gave us a menacing welcome as we stepped onto this otherwise fragile little patch of nature.

What makes this sort of ecosystem so unique is the sphagnum moss that forms its substrate. The moss releases great amounts of acid, creating an environment with a pH that can be as low as 4.0. Only certain very specialized plants can survive in these conditions. Cranberries, for example. Also pitcher plants and sundews – two insectivorous plants found at the Buckeye Lake bog. Also present were two species of orchid, the grass-pink orchid (Calopogon tuberosus) and the Snake-mouth orchid (Pogonia ophioglossoides).
















This bog ecosystem is very fragile, and ephemeral by nature. Bogs generally exist when former depressions fill with water, then moss, then other plant life. They are but a stage in the succession from open water to marsh to swamp and thence, perhaps, to solid dry land. This particular bog is especially vulnerable to change. The plant life found there is normally found much further north – it was pushed down by the glaciers that covered this land some 11,000 years ago. And, it is surrounded by a large alkaline lake that is slowly eroding away at the remaining bog island. The island was some 50 acres in size in 1830. By 1910, 45 acres remained; by 1955 it had dwindled down to only 23 acres. Presently there are a mere 11 acres left of this relic of the past.

Both humankind and nature are eating away at the bog. Buckeye Lake is heavily used. Boat-wakes and the pitter-patter of human feet physically damage the ecosystem. The alkaline waters of the lake encourage the decomposition of the sphagnum mat, while marsh trees (such as red maple) and other vegetation (various ferns, the aforementioned poison sumac, buckthorn) invade the island, further changing conditions.

I’m glad I got to see this little natural curiosity while it still exists. To read more about Buckeye Lake and the Cranberry Bog, visit: http://en.wikipedia.org/wiki/Buckeye_Lake

Interested in bogs in general? Check this out: http://en.wikipedia.org/wiki/Bog



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