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The trend to shorter grasses culminates in the Southern Short Grasslands of the High Plains. Here, in an area once memorialized by Coronado as a land of “very small plants,” the vegetation is dominated by a ground-hugging mat of grama and buffalo grass. Yet here, too, there are subtle shifts. For if the grasslands diminish in height from north to south, they shoot up from west to east as they escape from the rain shadow of the Rockies. This trend is reflected in the transition from the short-grass prairies of the west, with their carpet of stunted plants, to the multilayered, knee-high vegetation of the Nebraska Sand Hills and the Southern Mixed Grasslands.

On the eastern flank of the plains lies the tall-grass-prairie region, so named for the luxuriant stands of big bluestem and Indian grass that grow—or, at least, once grew—there. “The grass is so very high that a man is lost amongst it,” reported explorer Pierre François-Xavier de Chevalier as he crossed southern Wisconsin in 1761. Bright with brown-eyed susans and other flowers, these magnificent prairies extended from the Northern and Central Tall Grasslands south through the Flint Hills to the Blackland Prairies of east-central Texas. Many of the same species of grasses are also found, as an understory, in the juniper breaks of the Edwards Plateau Savannas and in the hickory-and-oak woodlands of the Cross Timbers Forest and the Southern Prairie-and-Oak Transition.

And finally, right out in the middle of everything, stand the lonely, displaced islands of ponderosa pine, white spruce, and paper birch that make up the Black Hills coniferous forest.

The ecological interactions that find expression in these varying landscapes have been at work for thousands of years. Even today, characteristics such as average temperatures, precipitation, length of growing season, and drainage patterns provide the physical framework or, one could say, the loom on which the fabric of the Great Plains ecosystem is woven. Yet for all their continuing importance, these long-term physical features are no longer the only powers in the land. Other interests have taken over; other hands are pulling threads. Those hands, of course, are human.

Over the last two hundred years, human beings have hit the prairies with the force of a major geological crisis, triggering not only extinctions and extirpations—of plains wolves, plains grizzlies, plains elk, plains bighorn sheep, free-ranging plains bison—but also dramatic shifts in the vegetation. Taken as a whole, the Great Plains grasslands now rank as one of the most extensively altered ecosystems on Earth. There is scarcely a patch of ground where we have not left our footprints. The southernmost Short Grasslands, for instance, are as sun-baked and arid a country as you could ever expect to see, yet even there an estimated 29 percent of the ecoregion has been brought under cultivation. The surviving native prairie in the region is now devoted to livestock or converted to ranchettes, on the advancing front of urbanization. In the mixed grasslands, by contrast, the percentage of land under cultivation rises from 15 percent (in districts with scant precipitation) to over 99 percent (where conditions are most conducive to crop production). And in the tall grasslands, with their relatively generous climate and deep, black earth, as much as 99.9 percent of the native grasses have been plowed under to make way for agriculture. Largely as a result of this destruction of natural habitat, at least 464 prairie species have declined to such rarity that their long-term survival is in question, and more names are added to the list with every passing year. (This tabulation includes only species that have been officially designated as at risk of extinction, either locally or nationally.) Of this total, a majority are unique organisms found exclusively, or almost exclusively, on the Great Plains grasslands.

The Foothills Grasslands of Waterton National Park, Alberta, bask in the autumn sun. This ecoregion not only benefits from the trailing edge of storms borne over the mountains but also enjoys relatively mild and bright winters, thanks to the influence of chinook winds.

These trends are deeply troubling, and we could easily get lost in the dark. To find our way forward we will have to be sure-footed, willing and able to move quickly from sorrow to hope, from past to present, from celebrating wildness to accepting and honoring our own accident-prone presence. We will need to see both the splendor of the life that has faded away and the abundance that still extends across the whole wide world of the prairie in every direction. For however diminished, the Great Plains are blooming and buzzing and wriggling and squirming with wildlife wherever we look. In the Northern Mixed Grasslands ecoregion, for example—where as much as three-quarters of the natural habitat has been lost to the plow—there are currently no fewer than 13 species of amphibians, 18 reptiles, 72 mammals, at least 160 butterflies, 222 birds, and 1,595 species of grasses, sedges, and wildflowers. This gives the region a total “species richness index,” on the books of the World Wildlife Fund, of 2,095, much higher than many areas that are typically thought of as biodiversity hotspots. (By comparison, the rain forests of northern California have a richness index of only 1,710, while the Everglades come in at 1,855.)

On the Southern Short Grasslands, by comparison, where significant areas of natural grasslands remain intact as grazing land, the picture is brighter yet, with 17 species of amphibians, 61 reptiles, 86 mammals, 230 butterflies, 245 birds, and an astonishing 2,359 species of grasses and other nonwoody plants, for a richness index of 3,011. Although this book can’t introduce you to all those species—you’ll need the appropriate local field guides for that—it will explain how this abundance of life is sustained and renewed, season after season. Far from being a sacrifice on the altar of progress that we can dismiss from our thoughts, the prairies are still very much alive and worth caring about.

About This Book

In the riotous interactions of nature, everything happens at once—sun, wind, rain, growth, birth, death—and change ripples organically through the ecosystem. For the purposes of discussion, however, it has been necessary to isolate aspects of this holistic system and discuss them one by one, each in a separate chapter. Although the subject matter is tightly interrelated, each section has been designed to stand on its own, so the chapters can be read individually and in any order. Chapter 3, “The Geography of Grass,” for instance, provides a detailed look at the prairie grasses and their dynamic relationship with the extremes of a midcontinental climate. Chapter 4, “Secrets of the Soil,” ventures into the dirt—a life zone all its own—and introduces a few of the strange little creatures that live beneath the ground. In Chapter 5, “Home on the Range,” we come back out into the sunshine to ride through cattle country and find out how life is lived on the surviving expanses of native prairie. Chapter 6, “Water of Life,” by contrast, takes us knee-deep into the nearest prairie river or pond to look into the lives of ducks, shorebirds, fish, and other aquatic organisms. Chapter 7, “Prairie Woodlands,” examines the unexpectedly important role of trees in grassland ecology and asks what difference it makes that woody growth is now invading the prairies. Chapter 8, “The Nature of Farming,” studies the potential and challenges of croplands as wildlife habitat. And finally, Chapter 9, “Long-Range Forecast,” reconsiders the conservation status of the Great Plains—is this really the most endangered ecosystem on the continent?— and discusses a range of options for protecting and restoring its wildness.

But before we look to the future, Chapter 2, “Digging into the Past,” will take us back to the very beginnings of time and the great adventure of existence.