Battelle Darby Metro Park + Cedar Bog (Fen) Field Trip
After reading Jane Forsyth’s “Geobotany” article, I’ve come prepared with lots of useful information about the geology of Ohio. The state can be neatly divided into two parts, that of the approximate Western and Eastern halves of Ohio. The Western part of the state consists of limestone that has been eroded down to create a flattened landscape, as the rock is quite nonresistant in humid climates such as ours. This contrasts with the Eastern half of the state, which consists primarily of sandstone (which is resistant in comparison to limestone) and on its western side is underlain by shale, which is less resistant and resulted in a landscape consisting of deep valleys and ridges or sandstone capped hills in the northern area of Cleveland. The original sequence of sedimentary rock strata in order from top to bottom are sandstone followed by shale, with a base of limestone. This layer saw a sort of ‘tilt’ that angled the sandstone deeper as moving more eastward, creating an arch shape that crests on the western side of the state. This gradually thinning layer of sandstone (the erosion resistant stone) meant that when erosive events or entities were present, they were able to flatten out the Western part of the state much more easily and consistently than in the East. Specifically, the river Teays (pronounced like the electric zapping weapon) was able to erode the land for about 200 million years, so to say that it left an impact would be an understatement. The river Teays in combination with the different rock layers is the primary reason for each of the halves of the state’s unique topography. Unfortunately for this river, some slow-moving glaciers of the Ice Age eventually led to the end of its fun with Ohio’s terraforming. The dramatic height difference from the sandstone hills in the east compared to the deep carved and flat limestone in the west was enough to create a glacial boundary in which the massive ice formations could not easily pass.
The glaciers carried with them a combination of boulders, clay, sand, and silt all mixed together to form glacial “till” and due to the aforementioned geologic events, the western part of the state consists of high quantities of lime and clay, while the eastern part of the state is void of these components and instead consists of gravel and sand that was washed out beyond the sandstone glacial ‘wall’. The resulting substrate in Western Ohio is relatively drain-proof, comprised, poor aeration and drainage, high pH (limey), and high levels of nutrient availability. Eastern Ohio parallels this with a high level or permeability and thus drainage overall as well as aeration. The sandstone bedrock creates an acidic (low pH) substrate where it’s exposed that is low in nutrient availability.
5 species that are found generally limited to limestone or limey substrates:
• Redbud
• Fragrant Sumac
• Hackberry
• Hawtorn
• Cinquapin Oak
(Don’t worry, later on in this post I’ve documented photos and descriptions of some of these species, but it feels very redundant to have identical information on the same post. I hope you can just as easily find them in the “Woodlands” section of Battelle Darby Metro Park, despite the higher powers instructing me to put these photos and descriptions at this location as well)
5 species that have distribution generally limited to high-lime and clay-rich substrates (Western Ohio glacial till):
• Sugar Maple
• Beech
• Red Oak
• Shagbark Hickory
• White Oak
5 species that have a distribution generally limited to sandstone hills (Eastern Ohio):
• Chestnut Oak
• Sourwood
• Scrub Pine
• Pitch Pine
• Hemlock
The distribution of some species such as the sweet buckeye and the hemlock, are determined by the glacial boundary. Sweet buckeye only occurs outside of the glacial boundary; however, it is peculiarly not found in the eastern boundary of the unglaciated region, making the climate of a more likely controlling factor. Another theory could involve the clayey and high-lime glacial tills impacting the repopulation capabilities of this plant. Hemlock, however, is also found I the unglaciated region of eastern Ohio but extends farther north than the sweet buckeye. This is likely due to the restriction of this species being in constantly cool, moist environments at the bottoms of valleys carved between sandstone. Even if the till may be less acidic, hemlock doesn’t mind if it’s got moisture and cooler setting. A third species, rhododendron, seems to be limited in distribution along the valleys that the ancient river Teays once occupied.
Wet Prairie:
This weekend my fellow botanists and I followed in the footsteps of those seeking riches and glory out west, however we prematurely concluded our journey just an hour westward of Columbus at the beautiful and diverse Battelle Darby Metro Park, as well as Ohio’s infamously improperly named Cedar Bog (more on that later). While we may not have struck gold in the literal atomic element sense, the vaults of our minds are brimming with knowledge from the species we found in the 4 varied ecosystems, and we all were luckier than leprechauns that Dr. Klips and Brett were able to share from their respective wealth’s of knowledge. Beginning our journey we arrived at Watts Wetland, a wet prairie consisting of low land and damp soil, teeming with (primarily) different wildflowers and grasses.
While the ground cover is dominated by forbs (wildflowers) and grasses, there is also a good spread throughout the ecosystem of other graminoids (that’s grass like plants including both grasses AND sedges). Shown below are a prairie grass known as Indiangrass, and a prairie forb known as Boneset. Indiangrass can be identified by its fuzzy stamens, yellow anthers, and their panicle inflorescence type which its flowers are ‘panicking’ out in every which way. Boneset has distinct leaves that are fused at their base and are members of the highly evolved Asteraceae plant family.
The key difference to spotting a grass verses a sedge is a simple rhyme “sedges have edges” and by contrast grasses do not and have stems that are rounded. Another neat trick shown below is to look at the leaf sheaths of the plant to see whether it is open (grass on left) or closed (sedge on right).
The dominant grass of this particular area is Big Bluestem, also known as Turkey’s Foot because someone decided that the heads of the plant somewhat resemble a turkey’s foot (I guess they’re not completely wrong).
No family is without a problem child however, and there do exist some pesky invasive woody plants such as the Eastern Cottonwood, as well as the American Sycamore. Thankfully work is being done to prevent these non-native wet prairie species from A. create an overstory layer which is largely absent in this ecosystem, as well as preventing B. the blockage of sunlight for species existing at lower layers of the environment.
If you’re in a pinch to figure out whether you’re looking at invader A or B, then I recommend you look no further than the leaves. While I didn’t manage to capture a closeup photo of each species’ leaves, the American Sycamore’s leaf is clearly lobed (with 3-5 lobes), and it’s hard to miss the distinct hear-shaped leaves of an Eastern Cottonwood (try to remember the two things that can make you feel warm and fuzzy – cotton and love!)
Woodlands:
Just down the road from our wet prairie ecosystem we found ourselves in the woodlands and with some much-needed shade as the day was beginning to heat up and wash away the morning cold. Here in the woodlands of Battelle Darby Metro Park we were on the search for those plants that like their substrate a little more basic (no, I don’t mean watered with Starbucks iced coffee and Taylor’s Swift’s latest album playing in the background). Many of the woody plants making up the overstory of these woods are calciphiles, loving the high pH that comes from a rich limestone environment.
Shown below are the Hackberry, Fragrant Sumac, Eastern Redbud, and Chinquapin (Burr) Oak, as well as some tips to identify each of these lime lovers.
Moving down a layer to the shrubs, one aggressive invasive species to keep a watchful eye out for is the shrubby honeysuckle. This plant has opposite, simple, entire leaves with red and round berry fruits.
Hanging out in the understory (maybe not ‘hanging’ per say but definitely at ground level!) you may stumble across White Snakeroot like I did, which has opposite broad leaves shown below.
A fun fact about this plant is that when it’s ingested by cows it can cause ‘milk sickness’ in the people that end up drinking that same cow’s milk. This is exactly how Abe Lincoln’s mother died, which typing out now seems less ‘fun’ and more ‘fact’ so maybe in the future I’ll refer to it as a fatal fact!
Cedar Bog:
Now onto the meat and bones of our trip, and the infamously, inappropriately, incorrectly named Cedar Bog, which is NOT a bog at all (dun dun duuun)! While I can’t answer who named the bog or why it aims to misinform residents and ecologists alike, I can answer what makes a bog a bog as well as the burning question I know you all must have: What is Cedar Bog if not a bog?! As is with the best things in science, there is a clever pneumonic device to use when differentiating a bog (which Cedar Bog is not) and a fen (which Cedar Bog in fact IS, and I will be further referring to as Cedar Fen for the remainder of this blog post). “Bogs clog and fens flush” is what you will see and hear from any of the helpful resources around Cedar Fen, and if you aren’t quite sure what toilets and plumbing have to do with ecosystems, I’ll break it down for you. As many of you are likely aware of the natural phenomenon known as “groundwater” (if you’re not a linguistics fanatic, yes, groundwater is water stored in various pockets and streams underground). Cedar Fen is in a particular location where the surface level is lower than the surrounding area. The came about when glaciers were moving south and had to contort around bedrock hills, leaving behind these cool ‘glacial hills’ also called end moraines. These moraines are pretty much made up of limestone gravel and sand, which if you’ve ever been to a beach and dug down more than a half foot you know that a lot of water can be ‘absorbed’ and kept in these porous materials. The same concept is true for these moraines and wouldn’t you know it, after the glaciers melted all that water remains in the surrounding hills. Just like how digging in the beach sand gets you to wet layers, Cedar Fen is positioned low enough that the rain-filled cold-water aquifers ‘push’ some of this water out into the remarkably unique landscape that is Cedar Fen. These same aquifers and porous drains, as well as surface streams, allow the land we visited to be “flushed” sort of like the way a toilet flushes. A true bog on the other hand (which Cedar Bog/Fen is not) is unable to drain due to dead plant matter piling up, creating a layer known as peat. As a bonus, the decaying plant matter makes the water in a bog acidic, which we just learned that the land in western Ohio is dominated by plants that enjoy a more alkaline taste to their water. Because of the unique geology and ecological conditions, numerous “conservative” plant and animal species can be found exclusively (or near so) in this environment! We’ll take a closer look at a handful of species that have high coefficients of conservation or CC’s, which essentially translates to species rarity. Within cedar bog there were two primary ecosystems that we traversed, the sedge meadows in the fen, and the swap forest close by.
Sedge Meadows / Fen:
Many uncommon plant species are located in sedge meadows, which lack individuals making a true overstory. Situated around the boarders of the meadow are Northern White Cedars, which often are found farther north, however the cold groundwater at Cedar Fen makes these trees feel right at home!
One common plant species found at the shrub layer is the Hoptree, which looks similar to poison ivy (just like our Fragrant Sumac discussed earlier…why are so many plants similar to this allergy inducing nuisance?) At the ground cover layer, we discover our first rare plant with a CC of 10 being Grass of Parnassus.
Also located in the same layer we can find the Shrubby Cinquefoil, which is just as conservative as the Grass of Parnassus having a CC of 10 as well!
We sure were lucky to have found these lovely species in the illustrious sedge meadows of Cedar Fen.
Swamp Forest:
Looking high above in the Swamp Forest you’ll find trees with no branches until well above 20 meters high. Some of these overstory giants often found around Cedar Fen are the Tulip Tree, although I’m more interested in more of these highly conservative plants, such as the bright purple/pink Swamp Thistle, which has a CC of 8 and is found at the ground cover layer. While not quite as rare as our other two specimen in the sedge meadow, I find the near bubblegum color of this species quite fascinating and I’m sure the pollinators appreciate such vibrant visual cues.
The only two woody vine species you’ll be able to find creeping about the swamp forest are the Moonseed Vine whose leaves are perfoliate and the Virgin Bower which is a member of the buttercup family and visually reminds me of a bad hair day!
One final highly conservative species, the Black Ash, has a CC of 7 and can be found in the shrub layer of the swamp forest, and we were lucky enough to spot close enough to capture this image where we can see the defined serrate margin that Ash trees are known for.
Until our next adventure fellow botanists, goodbye for now!