I've been researching the old Public Land Surveys again, in more detail. The information comes from books and microfiche stored at the Ohio History Center in Columbus. I photographed the books and microfiche files and brought it home. These records have three main pools of information:
The plat maps of the townships, which show outlines of prairies, wetlands, and some unique features such as Indian mounds. These were digitized into a GIS polygon geodatabase.
The species, diameter, and location of "witness trees" that were blazed by the surveyors at the corners of each square mile. These were digitized into a GIS point geodatabase.
The comments made by the surveyor summarizing the nature of each mile traversed. These were digitized into a GIS line database.
Once the database is complete it is possible to interpolate the data points/lines/polygons, with a little help from topographic and soil shapefiles. This map is the results of analysis of 24 PLS townships located between the Great Miami and Little Miami Rivers, between Dayton and Yellow Springs, Ohio.
This region contained oak-hickory forests, prairies, wet prairies, fens, oak barrens/savanna, open oak woodlands, oak woodlands overgrown with hazelnut shrubs, and hazel-oak thickets (prairies overgrown with hazelnut shrubs). Nearly all of it was composed of plant communities that had been modified or created by fire.
Native Americans had been using fire to manage the land for wildlife habitat, natural food production (such as hazelnuts and wild plum), easy travel, and quiet hunting, but burning the grasslands and forest understories continuously for much of the last 5,000 years. It's a world that was present far longer than the current white European culture that has predominated since 1800, but it has been mostly obliterated and forgotten. All that's left are some degraded scraps, but even these are beautiful and diverse. We lost so much before we even knew what we had. A culture that had learned to cultivate and manage natural systems to the benefit of many life forms was replaced by one that only benefitted humans.
By the time the land surveys were completed in the early 1800's the land had already begun to change. Many prairies and open oak woodlands were thick with brush from lack of fire, and bison and elk were nearly or completely gone. Some fire was still happening. As late as 1802 surveyor Israel Ludlow, while traversing a barren (oak savanna) in what is now Beavercreek Township recorded in his notes "In March, 1803, “much dead timber, fire burning the woods”.
To access an interactive map of this research click this link:
https://www.arcgis.com/home/webmap/viewer.html?webmap=a2e1c2d6b855485d9b082671d1cda8c7
Here you can read the actual surveyor comments for each section line.
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