1802: Survey of the Wilderness

Little Turtle cedes southwest Ohio to General Wayne at Treaty of Greenville

Let's begin a history of land use in southwest Ohio that created the conditions here now.  A good place to start would be 1802.  Southwest Ohio is still mostly a wilderness.  The revolution has been won.  It's been 7 years since the Treaty of Greenville that defeated the native americans and gave southwest Ohio to the United States.  Its been 17 years since the Continental Congress passed the Land Ordinance of 1785.  This legislation set up a system whereby the land of the "Northwest Territory", including southwest Ohio, would be surveyed and subsequently settled.

Depiction of early surveyors

In 1802, a rugged young surveyor named Israel Ludlow and his team set about to survey the forest wilderness of the Dayton area. Their task was to lay out a grid of townships 6 miles wide and 6 miles long. Each township was to be divided into 36 squares called sections. Each section contained 640 acres.  If a Section was divided into 4 pieces they were 160 acres and called quarter sections.  Using a compass and a long chain the survey crew would lay out the boundaries, called section lines, through the woods.  The chain was 66 feet long and contained 80 links.  When laid down 80 times a mile was traversed.  As they walked the section line the surveyors would make a note of each one describing the terrain.  when they had gone a mile it was time to mark the corner of the section.  To do this they marked forest trees with a hatchet.  They had to know the different kind of tree to distinguish each corner.  They also measured the trees diameter.  My doing this in a consistent manner they not only laid the land out for settlement, they made a pretty good record of the composition of the forest and the size of the trees.

Famous botanists including Paul Sears, Edgar Transeau, and Robert Gordon analyzed these surveyor records and produced maps of the "original" vegetation of Ohio.  In 1983 when I was a graduate student at Wright State University, my advisor, Dr. Jim Runkle, was analyzing some of these surveyor records to determine the pre-settlement condition of the outstanding woods at Wright State.  I was fascinated by these records and started studying them myself.  One thing that was interesting was the maps Ludlow made.  They had curious shapes drawn on them.  After matching the map with the notes it became clear that these were actually the boundaries of prairies and open wetlands that existed at the time.

beech-maple forest

Several years later Dr. Runkle and one of his students, Jodi Forester, analyzed the surveyor records in even greater detail, and made a GIS layer of the presettlement vegetation of the Dayton area.  They used the same classification system Robert Gordon did when looking at all of Ohio, but could zero in on more detail for our region.  Pre-settlement plant communities identified for our part of the world included:

oak-hickory forests, oak-maple forests, beech-maple forests, mesophytic forests, bottomland hardwood forests, elm-ash swamp forests, tallgrass prairies, wet prairies/fens, and hazel/plum shrublands.  Here is a map showing the distribution of these plant communties.