Along this fossil highway, even though it lies in the bottomlands that have always belonged mostly to the trees, I am walking in the time of the birth of the tallgrass prairie, that epoch when turfy perennials - bluestems and gramas, panicums and ryes - began covering the American interior as the old sea, now turned to a limestone anchor, once did. Down in here, the rock is the worn concrete, yet, as hard as it is, the cement road is nevertheless a fissured seedbed, a string of a glade full of brand-new prairie, an extinct highway giving birth to grassland.
Now: I've walked half this remnant, and I've found big bluestem and little bluestem, silvery bluestem, cord grass, wild rye, sunflower, bundle flower, catclaw sensitive briar, and also plants of the woodlands, including a clump of garden iris from I don't know where. But this strip is not a relict Pleistocene prairie because there probably never was much grass in this low spot in the bottoms: a vestigial highway, yes, but a new prairie. The native forbs and grasses have come in on the wind and maybe on the floods, and now they have roots under the pavement, and soon the prairie plants will need fire to clear away the shading and moisture-sucking trees, and until then the infant prairie can do little more than begin.
Prairie birth: in an earlier time, men believed the grasslands came as a consequence of infertile ground, or an absence of coarse soil material, or from glaciation, from bison trampling, lightning fires, Indian fires, from persistent wind, drought, temperature extremes.
But Chase County has good soil of various composition, the ice sheets did not reach here, and the temperature range and rainfall differ only a little from the woodlands of Missouri. The other "reasons" - fire, wind, grazing - contribute less to the birth of prairie than to its maintenance. No: the source of the prairie is its midcontinental position, far from tempering seas, where it lies under an eolian cleavage zone that mixes westerlies, wrung dry by the Rocky Mountains, with humid air from the Gulf: here, inches of evaporation and precipitation are nearly equal, and here, above my head, the rain- shadow of the Rockies meets in commensurate strength the humid Gulf fronts so that this land can grow ten-foot grasses and ninety-foot sycamores, and which one prevails depends mostly on one thing: fire. In the last half-century, the balance has careened toward trees because white men have suppressed the keeper of the grasses. To the prairie, the voice of the Great Mysterious speaks in three tongues: water, wind, flame. This glade beginning in the abandoned highway has heard the first two, and now this slender quarter mile of incipient prairie could use a tossed cigarette from a Santa Fe trackman so that the highway can flourish as never before.
Copyright (C)1992 by William Least Heat-Moon. Reprinted by permission by Houghton Mifflin Company.