Troisième Age, a Blue Ash tree at Ashland which pre-dates Henry Clay. Perhaps this tree was part of a woodland pasture that makes up the Inner Bluegrass landscape. |
I am deep into a project which will be an invitation to explore one's own 'kith'. Kith is an older english word that we only use now when we say 'kith and kin'. This, of course, refers to kin for the most part, but I learned from reading Lyanda Lynn Haupt's engaging book, Rooted,* that kith actually refers to a familiarity with one's home turf.
Through a bit of serendipity, a course on Dirt Discipleship was offered through the Center for Deep Green Faith. I jumped at the chance to enhance my earthy connections. As part of the course we are to select a patch of dirt to 'experiment' upon. I thought this would require digging up dirt and testing for...acidity? chemicals? evidence of past lives? So, I selected a patch in my yard. It is behind our 8' x 4' compost enclosure--should be fertile territory!
A backyard corner selected for lab work |
I wasn't as clear on the geology of this patch of dirt. My working knowledge going into this experiment was that the Inner Bluegrass is a plateau and the landscape is basically a savanna. This is where things got interesting for me. I googled the geology of the Inner Bluegrass (of course) and learned that the basic landform is the result of the Cincinnati Arch a geologic limestone structure that pushed up from beneath present day Tennessee toward the close of the Paleozoic era. A dome composed of limestone formed in what is now the Inner Bluegrass. The limestone eroded over millions of years exposing the oldest layers of Ordovician limestone around. The resulting landscape is called a karst landscape (karst is a limestone region with underground drainage and many cavities and passages due to the limestone's porosity).
As I was reading about the geology of the Inner Bluegrass, I was directed to Tom Kimmerer's website and realized I was reading excerpts from his book Venerable Trees: History, Biology, and Conservation in the Bluegrass. I have this book in my collection since I am a tree lover. I pulled the book from my shelf and proceeded to learn how my home landscape came to be. It was quite surprising (and I wondered why this information hadn't landed before). I knew about the limestone, which gives horses their strong bones and amply supplied material for the stone walls which accent the pasture lands. What I didn't know is that this karst topography makes the Bluegrass region prone to drought even though there is plenty of rainfall generally. In Kimmerer's book he includes a Drought Index chart with information based on dendrochronology (tree-ring analysis). The chart shows an extreme drought beginning in 625 and lasting for 368 years. Now that is a drought! So, Kimmerer's posit is that the karst and drought are factors in the establishment of the Inner Bluegrass landscape. He proposes a third essential element that is quite intriguing: an abundance of bison. This abundance, he suggests, is evidence that the Bluegrass landscape was mostly woodland pasture, with some variations on the density of tree growth, but plenty of grazing opportunity. The bison might have also kept Indigenous tribes from creating permanent settlements in the area. Apparently, the bison were not fazed by mere human-built fencing or housing and would just stampede right over these structures. There is only one known permanent Indigenous settlement known to have existed in the Inner Bluegrass area. It was abandoned around 1754, the time of an extended drought. Bison helped to maintain this landscape by grazing heavily and then moving on to saltier and wetter opportunities. Since they did not feed on trees, the trees were left to grow and developed deep roots that kept them from falling victim to droughts (though perhaps not a 368-year drought!) As Kimmerer states: "It appears likely that drought, karst, and bison were the three main factors that created the conditions under which woodland pastures developed with little human influence."***
I've long known that bison were the original road creators in Kentucky--there are quite a few important corridors that were originally buffalo traces. But, I didn't know that bison could be an essential factor in the 'cultivation' of our Inner Bluegrass landscape.
Now we are famous for our fields of bluegrass, but that grass is not native to Kentucky. What grew when the bison roamed freely were other grasses and lots of cane (Kentucky bamboo) and clover. In particular, running buffalo clover was prominent. The relationship between bison and clover was symbiotic because the buffalo would feast on the sweet clover and then helped to propagate the clover by 'processing and sowing' it, and also disturbing it a bit. I've written about this is a previous blog.
Running Buffalo Clover is being encouraged at Ashland Estate |
It turns out that this bit of backyard dirt has a more interesting story than I thought. It is also part of a woodland pasture landscape that does not exist anywhere else in North America. It has more in common with the 'wood pastures' in Northern Europe--but that is a story for another time...
I walked over to the Arboretum to check on their information about the Bluegrass Region and I'll post the photo of a nice summary of how the Bluegrass region came to be. Note: Kimmerer has a little different idea around woodland pasture/savanna and the use of fire to create the grasslands. If you live in the Lexington (KY) area, I encourage you to visit the Arboretum. They have a really wonderful Walk Across Kentucky feature. You can walk among the trees and vegetation that grows in each of the regions of Kentucky. And there is an Inner Bluegrass woodland remnant that you can wander through--a real treat!
* Haupt, Lyanda Lynn. Rooted: Life at the Crossroads of Science, Nature and Spirit. New York: Little, Brown Spark, 2021.
** Ashland Estate was Henry Clay's home. Henry Clay came to Kentucky as European people were heading west from Virginia. Clay began to acquire land for his estate in 1804. It is now a museum and arboretum. In fact, many of the trees that made up the woodland pasture landscape are growing at Ashland. It is a wonderful green space in our community. For more information, visit: henryclay.org
***Kimmerer, Tom. Venerable Trees: History, Biology, and Conservation in the Bluegrass. Lexington, KY: University Press of Kentucky, 2015. p. 84. This book is a font of wonderful information, including a listing of all the trees that make up the Inner Bluegrass landscape.