Across much of Kansas, the historic Santa Fe Trail closely follows our target latitude line and, not coincidentally, also closely follows the Arkansas River, the major surface water source in this part of the country.
We entered Kansas at Fort Scott,

one of a series of forts built along what was intended to be the permanent boundary to Indian territory, and later functioned as protection for settlers using the Santa Fe Trail.
This is prairie country--rolling dry hills had replaced the green of the Midwest heartland. The Tallgrass Prairie National Preserve (38°26', 96°33'),

was established 12 years ago in eastern Kansas.

Because of local opposition to a "real" national park, the legislation creating the park limited National Park Service acreage to about 100 acres; the rest of the 11,000 acres are owned by the Nature Conservancy and considered private land. Some of that history was told by William Least Heat Moon in his book
PrairyErth, which focused on this Kansas county. Moon wanted to write about the "center" of the country, and traced diagonal lines from the 4 corners (northwest to southeast and southwest to northeast), finding that they intersected here--a calculation that also coincided with the 38th parallel. The week after our visit, 20 bison were scheduled to be introduced to the park, brought from Wind Cave National Park in South Dakota.
We visited Pawnee Rock, a major landmark

along the Santa Fe Trail that was unfortunately quarried later. A viewing platform shows how tall the big black rock used to be. Not far away was Fort Larned ,

on the Pawnee River, serving travelers on the trail.
In Dodge City, Queen of the Cowtowns,


we reached cattle feedlots and the 100th Meridian--the 100 degrees West latitude line. From there on, as we moved westward, we would come to appreciate "the line between the humid east and the arid west," as recognized by John Wesley Powell. In land with less than 20 inches of annual rainfall, Powell wrote, "agriculturalists will early resort to irrigation."
In western Kansas, Garden City is home to the Sandsage Bison Range, (37°56', 100°54'),

3670 acres where Tom Norman, the State Park manager showed us the herd of 90 bison , about to be reduced to 60 with an annual round-up. Bison have been here ever since "Buffalo Jones," one of the founders of Garden City, rescued a few

of the last remaining buffalo from extinction. A few scattered trees are also on the preserve, evidence of an attempt to create the Kansas National Forest Reserve early in the 20th century. Millions of tree seedlings were planted, but climate and soil realities doomed that quixotic project (a fascinating bit of history we will explore in the book to come).
The overlapping story of the Ogallala Aquifer, also part of our travels through this region, comes in our next post.