Please Note: The OHS Archaeology Blog is happy to announce that from time to time we will be sharing our blog space with Bob Glotzhober, OHS Senior Curator of Natural History. While not exactly of an archaeology bend his postings will be interesting reads and perhaps provide a few different points of view on the environment in which ancient Ohioans lived and found so inviting. Welcome Bob!
Orchids versus White Cedars versus Tulip Poplars Bob Glotzhober, Senior Curator of Natural History, Ohio Historical Society
Fifty years ago those involved with protecting natural areas and the rare species that depend upon them often thought that all one had to do was to purchase the land, put a fence around it to protect, and leave it alone. Let nature follow its eons-old laws of natural processes. Do this, and the “Balance of Nature” would take care of everything else! Brighter minds, even fifty years ago, knew that setting the land aside was not enough. Most nature preserves, especially in the eastern United States, are in reality "Postage Stamp Preserves". Cedar Bog is only 450 acres and much of that is buffer land to protect it from surrounding farmland and potential development. Once, that area was estimated at 7,000 acres. In such a huge landscape, perhaps most plants and most animals could survive – finding protection in one area if some natural or man-made disaster threatened another area. In today’s landscape, we usually cannot afford the slightest impact on a small, rare habitat without losing that last of an important cog in the wheel that keeps that landscape and its inhabitants thriving. Cedar Bog Nature Preserve is managed by the Ohio Historical Society, with daily operations handled by our partner, the Cedar Bog Association. See these two websites for more information on OHS http://ohsweb.ohiohistory.org/places/nw02/ and the Cedar Bog Association http://www.cedarbog.org/ ). Cedar Bog is one of the most significant natural areas in Ohio, with one of the greatest concentrations of rare and endangered species per acre of any place in Ohio. It is recognized as both a National Natural Landmark, and as a State Nature Preserve. One of the really special plants at Cedar Bog is the Small Yellow Lady’s-slipper Orchid, (Cypripedium calceolus var. parviflorum). At Cedar Bog we know of only seven plants of this orchid – three of those being rediscovered just last spring. While it had been known from two other Ohio locations, it now appears to only at Cedar Bog and one other site in Geauga County, and is State Endangered. One of our two populations, which has four plants, had a couple of Northern White Cedars fall across the top of the site late last spring. While these plants like a mix of sun and shade, the dense, close cover of these cedars could threaten the health and survival of these orchids. So, in mid-March, while most herbaceous plants are still dormant, site Manager Eric Doerzbacher and myself set out to surgically trim several cedar branches and to totally remove one fallen tree. This operation was probably more art than science – as none of the experts seem to know exactly how much shade is enough and how much sun is too much. But after consultation with several of our state’s most knowledgeable field botanists last spring, Eric and I tried to carefully remove just the right amount, while being extra careful not to trample and compact the soil holding the roots of these rare perennials. If we were successful, in a couple of months the orchids will shoot up above the surface of the ground, unfold leaves and thrive in their restored environment. The problem of protecting the Small Yellow Lady’s-slipper Orchid is augmented by the fact that the trees we had to remove are also a Potentially Threatened species in Ohio. The Northern White Cedar (from which Cedar Bog gets its name) is also known as Arbor Vitae, or scientifically as Thuja occidentalis. This is in contrast to the Arbor Vitae that is most often planted around homes, which is Thuja orientalis, an import from Asia. More recently more people are planting cultivated varieties of the native species, an improvement in that native butterflies, moths, beetles and other animals are adapted to the native species and not to the Asian species. At any rate, the native species is known from only ten of Ohio’s 88 counties, and even in those ten is rare – and is listed as Potentially Threatened. Therefore, we impacted one rare species in order to protect an even rarer species. Talk about potential conflict! Actually, since 1987 staff members of the Ohio Historical Society have been cutting lots of Northern White Cedars at Cedar Bog. The Sedge Meadow habitats, which are home to the greatest number of Cedar Bog’s endangered species, tend to become invaded by the Northern White Cedar in a naturally occurring process known as ecological succession. To protect the Sedge Meadow, we had to go in and selectively hand cut out invading cedars. All this time, we were also concerned about the Cedar Swamp woods, as they too are threatened with succession by invading hardwoods, especially the fast growing Tulip Poplars, which thrive on the rich soil and somewhat drier soil, made drier by the growth of the cedars. So, we cut common Tulip Poplars to protect the Northern White Cedars, and cut Northern White Cedars to protect the Sedge Meadows. It all requires careful watching and monitoring of the changes and the impacts on the rarest species and balancing the desire and need to let “nature take its course” with the limitations of a small preserve, surrounded by heavily managed landscapes. Managing a nature preserve, when we study the ecological functions and the limitations of our postage stamp preserves, is really not an oxymoron at all, but an important necessity.