I turn west toward the Flint Hills, and the smoke of burning grass reaches me before I reach them. I know the ecology of this landscape, so I should have been expecting it. At least I should have recognized it immediately, but it takes some miles on Highway 50 before I piece together what is happening or even register the distant haze.
April in Kansas, the land holds onto its late winter colors. There is a scant hint of green dusting the landscape. Yet it is not vibrant enough to fool the land into fully waking. There hangs the sweet ashy smell that burning prairie gives, but it is too subtle to draw attention to the landscape. It is the faint residue of singed andropogon, bluestem, which in another season the cattle would ruminate, which in another time the bison would have grazed. As I speed closer to the Flint Hills, the smoke in my car thickens and I realize this is not some localized trash fire. I look west towards the horizon and see an orange haze hanging over the landscape.
The silhouette of the Flint Hills looms in the distance. Flat, treeless land flanks the highway, but five miles ahead are flat-topped hills, irregular in position and varying in height. At random points in the horizon, wide plumes of amber ash rise up and coalesce, creating a low canopy that rolls east like a tide. After crossing Bull Creek, which is marked on the land by riparian cottonwoods training their roots into the damp earth, the road begins to rise and the first of the long, low hills are beside me. They look like a pod of golden whales swimming across the prairie. Soon they thicken so there are no more fields at all, just prairie-covered hills organized into cattle pastures by gossamer barbed wire. The Flint Hills are a large landscape 90 miles across and 160 miles north to south, where it reaches into Oklahoma.
The Flints Hills landscape begins its story over 250 million years ago in the Permian Period, when inland seas covered much of central North America. During the Permian, marine deposits in the band we know today as the Flint Hills built alternating layers of shale and limestone — mud and shells — on the seafloor. When the North American plate began moving west and the seas drained, these seabeds became the bedrock of Kansas. Erosion here was caused by water and wind as the landscape was too far south to be touched by glaciers. But erosion worked irregularly. The hard white limestone served as a cap resisting the elements. When breached, however, the softer shales quickly wore away. The resulting topography is an irregular landform of tables and benches. The limestone layers, in addition to containing Permian fossils also contained hard chert, or flint, inclusions. These being even slower to erode accumulated as flintstones on the surface of the landscape.
The Flint Hills are also known as the Bluestem Pastures, after the dominant prairie grasses that growth here. Bluestems, a variety of species in the Andropogon genus, are an important component of the tallgrass prairie. But it is not truly accurate to call this prairie tallgrass, because it also contains many forbs, flowering herbs that give this landscape rich diversity. This prairie once covered all the Flint Hills and a much larger T-shaped region with arms stretching from Mexico to Manitoba and a trunk reaching Michigan. The tall grass prairie is well watered. Manhattan, Kansas, the urban center of the Flint Hills, receives as much rainfall as wooded Pittsburgh. But here the rain is seasonal. Less than three inches of precipitation falls in the three winter months out of a total over 35 inches. Dry winters make the landscape prone to regular, broad fires, enough to prevent trees and other woody plants from surviving, except in the damp river and creek beds and the prairie potholes. The latter are in the northern prairies, formed during recent glaciations. In eastern Kansas there are no potholes. The Flint Hills are well drained by the Kansas, Cottonwood, and Walnut Rivers and their tributaries.
In past centuries the landscape was less fragmented and fires once started by lightning strikes or human intervention would burn until it hit one of these valleys. The herbaceous grasses and forbs of the tallgrass prairie, which grew high and thick every wet summer supported vast herds of bison. In turn, the bison, flintstones, and perennial rivers supported smaller but influential populations of humans. Autochthonous Indian nations such as the Pawnee, Wichita, Osage, and Kansa inhabited and lived off the landscape.
With the advance of the European-American settlers, vast acreages of the tallgrass prairie were plowed for agriculture. But the rocky, hilly terrain of the Flint Hills was inhospitable to the sodbusting plows of European farmers, and the landscape retained much of its original tallgrass prairie. Still there were changes to the landscape. Where bison roamed, cattle could graze.
The new immigrants extirpated the bison, uprooted and displaced Indian nations, and hazed cattle in. Over the next hundred years, land division and uses grew complex. resulting in a more fragmented landscape. Roads and railroads, barns and houses, stone walls and barbed-wire fences partitioned the landscape. But most importantly, fire regimes changed. Some patches, homesteads for example, were kept burn free. Others, pastures, were burned off in patches. Ranchers understood early to burn the well-watered pastures in late winter if they wanted to keep the grass and forbs growing and discourage woody plants. Grassland fires are low and burn to the edge of a road but are unlikely to jump it. Where fires were suppressed trees gained an edge. Without fire, woodlands readily succeed. The tallgrass prairie needs to burn if it is going to stay prairie. We know this now. Today land managers prescribe burns. Fortunately, cattle ranching, which is deeply embedded in the modern landscape, persisted with a burning regime that resulted in the Flint Hills containing the largest remnant tallgrass prairie in North America.
I tune to the Flint Hills public advisory radio to hear stories of the local landscape and updates on the burn season. The latter is hardly necessary. The air is thick and smells like incense.
In Strong City, turning north onto KS 177 brings me to my destination, the Tallgrass Prairie National Preserve. The preserve was established in 1996 as a partnership between the National Park Service and The Nature Conservancy. The origins of the preserve boundaries reach back to the establishment of the Spring Hill Ranch in 1878.
I have the waning afternoon to explore the preserve. Many of the original ranch buildings, made of blocky white Flint Hills limestone still stand. The main house gives a sense of the ranching enterprises that shaped today’s landscape. This season’s burn schedule is evident. All the land to the east of KS 177 is blackened stubble, the grass is charred from the shoulder, across the prairie, and over the hill. Everything in view is black. The rangers advise me on which trails are close to burns and which bison. On the west side of the road the hills remain the color of winter straw. A lone brown cottonwood marks where two drainage channels converge. The sun diffuses into a smoky orange afternoon. Early April in Kansas in the Flint Hills has a painterly beauty, and a sense of solitude. A strong sense of place has me determined to return for a deeper stay.
This preserve is one of a handful of toeholds of tallgrass landscape protection. It is a landscape of bison, bluestem, and burning that is scientifically managed to mimic an older, wilder landscape. It is an island of tallgrass prairie is a sea of monetized land.
The tallgrass prairie in North America historically covered 400,000 square miles. The Flint Hills are 9,936 square miles. Today, the federally supported Tallgrass Prairie National Preserve protects 10,894 acres or 17 square miles, about 0.0042% of the historic prairie and 0.17% of the Flint Hills. To me, it doesn’t seem enough.