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To the south of the High Plains lie the limestone hills of the Edwards Plateau, or Texas Hill Country—a world in itself—where the rolling countryside is broken by domed upwellings of rock, deeply cut by streams, and eaten away underground to form a honeycomb of sinkholes and caves. The Edwards Plateau, in turn, is bounded in the south by the terraced ridges and eroded canyons of the Balcones Escarpment, which slashes across Texas at the southern limits of the Great Plains grasslands.

To the northwest of the Edwards Plateau lies the broad Pecos Valley and a landscape of spectacularly eroded caverns, sinkholes, and steep-walled limestone cuts. And north of the Pecos are the shadowed moonscapes of the Raton Section, where mesas capped with lava compete for attention with contorted badlands and the burned-out cones of Capulin Mountain and other long-extinguished volcanoes. From there, it is on to the broad, terraced valleys of the Colorado Piedmont, literally “foot of the mountains,” where the waters of the Arkansas and South Platte rivers have, over millions of years, stripped away layer after layer from the original High Plains surface. (This dramatic, if localized, lowering of the surface explains, for example, why the road heading east out of Denver tracks steadily upward for the first half hour or so, as it climbs out of the South Platte floodplain and onto the surrounding High Plains benches.) The effects of water erosion can also be seen on the rugged Missouri Plateau and the deeply dissected valleys of the Plains Border region.

If water has cut into these landscapes, wind has smoothed them out. For example, the southeastern edge of the Platte River valley is softened by a broad belt of curving, undulating sand dunes that were deposited by dust storms sometime during the Ice Age. Similar formations, shaped by similar forces, are also to be found strewn up and down the drier, western side of the Great Plains, from the Great Sand Hills of southwestern Saskatchewan in the north to the Mescalero Dunes of the Pecos Valley. And right in the middle of the map lies one of the prairies’ little-known natural wonders—the Nebraska Sand Hills, a region of whale-backed, grassy rises and prairie wetlands that, at an area of 24,000 square miles (62,000 square kilometers), ranks as the largest field of sand dunes in the Western Hemisphere. These sandscapes were put in place by the relentless northwest winds that have been coursing across the landscape for millions of years.

With so few barriers to stand in their way, these same winds have had the run of the entire Great Plains region. Although their influence can be seen in many parts of the country—for example, as ridges of windblown silt along both the South Saskatchewan and upper Missouri rivers—their touch is most obvious in the eastern and southern regions of the Great Plains. These include not only areas of the Colorado Piedmont and the High Plains but also the “low plains” to the east, notably the rolling hills of the Plains Border country, the Osage Plains, and the Glaciated Central Lowlands. Much of this sweep of country is blanketed in deep, contoured drifts of fine silt, or loess—pronounced “luss”—another gritty, wind-borne by-product of glaciation. The result is a gently undulating landscape of soft, rolling hills and, in places, extraordinary bluffs, like the delightfully eroded and unexpected Loess Hills of western Iowa.

The northern plains region, by contrast—north and east of the Missouri River, from Alberta to Manitoba and south through the Dakotas—is less apt to be buried in loess, but it nonetheless bears the imprint of the Ice Age. Here the terrain is an unmade bed of glacial rubble, or till, lying exactly where it dropped when the ice sheets retreated from the landscape ten thousand years ago. And protruding above this jumble of knobs and kettles is an assortment of sprawling, flat-topped uplands, including Turtle Mountain, Wood Mountain, and the Cypress Hills, which straddle the boundary between past and present. Like miniature versions of the High Plains, they are the last surviving remnants of an ancient, preglacial landscape that has otherwise been lost to erosion.

Finally, and most surprising of all, are the honest-to-goodness mountains that jut up out of the northern plains, particularly on the unglaciated reach of country south and east of the Missouri River. From the glowering Black Hills to the jagged Crazy Mountains, they stand as a peak experience (if you’ll forgive the pun) for anyone who has been led to believe that the prairies are monotonous.

> THE MOST TREMENDOUS ROARING

The Corps of Discovery led by Captains Meriwether Lewis and William Clark spent the winter of 1804–5 in the villages of the Mandans and Hidatasa, in what is now central North Dakota. It was likely there that they first heard stories about the ferocious “great white bears,” or plains grizzlies, that had spilled the blood of so many warriors. But when the Corps members met their first bear, at the confluence of the Missouri and Yellowstone rivers the following spring, the kill was surprisingly easy.

“The Indians may well fear this animal equipped as they generally are with their bows and arrows,” Captain Lewis mused in his journal, “but in the hand of skillful rifle men they are by no means as formidable or dangerous as they have been represented.”

That was April 29, 1805. Six days later, Lewis’s partner, Captain Clark, was singing a different tune. “The river rising & current Strong & in the evening we saw a Brown or Grizzly beare on a sand beech,” he wrote. “I went out with one man Geo Drewyer & killed the bear, which was verry large and a turrible looking animal, which we found very hard to kill we Shot ten Balls into him before we killed him, & 5 of those Balls through his lights. This animal is the largest of the carnivorous kind I ever saw.”

Plains grizzly bear

Lewis described the same encounter in greater detail: “It was the most tremendious looking anamal, and extreemly hard to kill notwithstanding he had five balls through his lungs and five others in various parts he swam more than half the distance across the river to a sandbar, & it was at least twenty minutes before he died; he did not attempt to attack, but fled and made the most tremendous roaring from the moment he was shot . . . . Capt. Clark thought he would weigh 500 lbs. for my part I think the estimate too small by 100 lbs. he measured 8 Feet 7½ inches from the nose to the extremety of the hind feet, 5 F. 10½ Ins. arround the breast.”

Once widely distributed across the Great Plains, grizzlies may have been most common in the major river valleys. They were extirpated from the region by the 1890s or early 1900s.

Then and Now

It is one thing to send our minds running across the contours of the Great Plains grasslands and their unexpectedly varied landforms. It is quite another to bring these spaces to life, to try to perceive them in their full, natural vitality and splendor. What would it have been like to step out onto the round bowl of the southern grasslands with Coronado in 1541, aware that at any moment our progress might be blocked by a dusty, pawing, milling herd of bison? Or, precisely 150 years later, in 1691, to have traveled with Henry Kelsey and his Cree and Assiniboine guides from Hudson Bay through the northern forest and onto the prairies of the Saskatchewan River country? What emotion would have seized us when a blocky, hunched shadow gradually resolved into the form of a massive and potentially lethal grizzly bear? Or what if we could slip back in time to 1805–6 (a mere two hundred years ago) and join Lewis and Clark on their famous expedition up the Missouri River?

Imagine: Bison beyond counting. (“I do not think I exaggerate,” Lewis wrote as he crossed the Dakota plains in 1804, “when I estimate the number of Buffaloe which could be compre[hend]ed at one view to amount to 3000.”) Flights of pronghorns at every turn. Elk coming up out of misty valleys to graze on the prairie at dawn. Bighorn sheep perched on the steep, crumbling walls of the Little Missouri Badlands. Wolves threading across the prairies, trailing the herds.

Two hundred years isn’t very long on the geologic timescales of planet Earth. These memories lie at the very threshold of the present, so close that we half expect to be able to walk into a fold in the landscape and encounter them. And something like this still occasionally happens when we stumble across a physical trace of the past, whether it’s a flaked stone tool that once belonged to a bison hunter or a shallow, saucer-shaped hollow that was worn into the dirt by generations of rolling, grunting bison. The animals have vanished, but the imprint of their flesh and blood is still on the land. It is all so mind-bogglingly recent.

There are not many places where the wild is as close at hand as it is on the Great Plains. In the Old World of Europe and Asia, no one can quite remember what “natural” looked like, because the land has been successively shaped and reshaped to meet human needs for hundreds or thousand of years. But in the New World of the prairies—right up to the moment when the settlement boom began— humans had lived off the natural productivity of this vast, sun-swept expanse of grass. From the beginning, the First Peoples had drawn their sustenance from the native animals and plants, experiencing both feast and famine as hunters and gatherers. This is not to say that they sat back passively and let nature take its course. They were active participants in the ecosystem, ready and willing to use whatever technologies they could command to improve their chances of survival. For example, they had no qualms about setting the prairies on fire, to green up the grass and draw bison in for the hunt. They tilled the soil of fertile river valleys and planted gardens of sunflowers, corn, and squash. They eagerly adapted to the new culture of firearms and horses.

Yet despite these human innovations, the underlying dynamic of the ecosystem—the interplay between climate and grasses, grazers and predators—remained robust. A landscape that had evolved to support large herds of grazing animals was still doing exactly that, as life ebbed and flowed in time with the seasons. Then, in the early to mid-1800s, the pace of change accelerated. In far-off Washington and Ottawa, ambitious governments began to assert their claim to the land and resources of the Great Plains. As a prelude to agricultural settlement, Native people were confined on reserves and reservations, whether by persuasion or by brute force, and the bison on which they depended—the multitudes of “humpbacked cattle” that had darkened the plains—were virtually wiped out in a bloody orgy of killing. Tellingly, the final stages of this slaughter were motivated by the discovery that bison hides could be cut and sewn into leather belts and used to power machines in the burgeoning industrial complex in the East. (The last free-roaming bison were killed in Canada in 1883 and in the U.S. in 1891.) Modern times had arrived on the prairies.

And then came the settlers, an onrush of humanity that reached full flood in the late 1800s and early 1900s. Determined to make a stand in this new country, the incomers quickly progressed from temporary shacks and shanties into substantial homes, making them the first people ever to establish permanent, year-round dwellings on the open plains. This was a bold experiment, occasioned with far more risk than anyone at the time seemed to recognize or, at least, was prepared to admit. But whatever the hazards, the way forward was clear. The object was to assert control over the ecosystem and redirect its natural vitality into the production of commodities that could be bought and sold on the world market. Beef, not bison. Wheat and corn instead of prairie wool.

The largest land animal in North America, a mature bison may stand almost 6 feet (2 meters) high at the shoulder and weigh as much as a ton. Here, a black-billed magpie takes advantage of the view, searching for insects stirred up by the bison’s hooves.

Arthur Savage photo

The result of this revolution is the landscape that we see today, a colorful patchwork of fields and rangelands, where geese feed in the stubble, foxes hunt in farmyards, and meadowlarks sing their hearts out on fence posts. These are the prairies that our generation was born to, and they are beautiful in their own right.

Yet the more we love this place as it is, the more we feel the pain of what it so recently was. The wild prairie ecosystem is gone. And this tragedy is compounded by the realization that we don’t even know exactly what it is that we have lost. “Civilization” and “progress” overran the grasslands with such an urgent rush that the ecosystem was disrupted before anyone had a chance to make a systematic study of exactly what was out there or to figure out how all the pieces interacted with each other. The people who might have had the most to teach us—the last generation of hunters and gatherers—went to their graves largely unheeded by the newcomers, taking their knowledge of the prairie and its life ways with them. We are left with little to guide us except for fragments of written descriptions in the journals of explorers and early settlers—partial lists of species, brief sightings, and offhand remarks—that leave many basic questions unanswered.

Male bison, seen here in the foreground, can be recognized by their burly physique and stout, inwardly curved horns. Females are somewhat smaller, with slender, straighter horns. What’s more, in spring and early summer, they may have small red calves in tow.

The depth of our ignorance is startling. Question: How many bison were there on the plains before the slaughter began? Answer: No one can tell us with any assurance. By working and reworking the available strands of evidence, experts have estimated the precontact population at anywhere from 12 million to 125 million animals, a variance that leaves more than 100 million bison in limbo. These days, experts acknowledge that bison once numbered in the millions and probably tens of millions, but that’s as far as they’re prepared to go. And if we cannot account for big things like bison, how much less do we know about the smaller and less conspicuous organisms—little things like insects and spiders, fish and frogs, rodents and songbirds—that lived and died in their untold variety and interest and abundance? Yet if the wild past is lost to us, we can still look ahead. Despite everything that has happened, it is not too late to acknowledge the natural forces that continue to animate the prairie world and that, even today, shape the lives of all its creatures.

> ABUNDANCE

The great herd running away,

The buffalo running,

Their drumming hooves

Send dust clouds billowing to the sky

And promise good hunting

The buffalo and her child approaching,

Mother and Calf coming,

Turned back from the herd,

Promise abundance.

CHAHIKSICHAHIKS (PAWNEE) SONG

Ecosystems and Ecoregions

It’s not really fair to blame our ancestors for their lack of ecological awareness. At the time the plains were settled, “ecology” as we know it had not yet been invented. Instead, the science of the day was focused on fixing life to a pin, labeled and safely dead, with the species laid out in straight rows and separate compartments. (This passion for “still life” was given concrete expression in the natural-history collections of nineteenth-century museums, those great mausoleums filled with pressed plants, dried skins, stuffed birds, and mounted insects—among them, many thousands of specimens from North American grasslands.) The conception of life as a tumultuous interaction between organisms and the world around them was of no great interest to a science that was largely content to follow in the footsteps of Linnaeus, collecting things and classifying them.

But on the fringes of science, new ideas had begun to stir. In 1866, for example, an eccentric German physician-turned-philosopher named Ernst Haeckel cobbled together two Greek roots—oikos, meaning “household,” and olgie, or “study of”—to describe a radical new approach to life science, ecology. Drawing his inspiration from Charles Darwin’s still-recent discovery that organisms are shaped by the environments in which they evolve, Haeckel described his new endeavor as the study of natural selection in action. It was, he said, “the investigation of the total relations of the animal both to its inorganic and organic environment,” including its relationships, whether “friendly” or competitive, direct or indirect, with all the other organisms in its surroundings. The essence of life, he hinted, lay not in a static array of species in a collector’s cabinet but in this wonderfully tangled web of interconnections.

By late summer, big bluestem—the characteristic grass of tall grasslands— often waves above the wild flowers, like the goldenrod seen here, and reaches into the lower branches of bur oaks and other trees.

This was a heady idea, more poetry than science, and for a long time, no one could figure out how to develop it any further. In the end, it took a pioneering biologist from Nebraska by the name of Frederic Clements to ground the new field in observation and hands-on evidence. With the native vegetation under assault all around him, Clements focused his attention on the ability of the wild prairie to recover after it had been burned over, plowed up, dried out, or otherwise disrupted. In a study published in 1916, he concluded that the prairie was a self-healing system in which, given the chance, groups of plants grew back in an orderly sequence, each wave creating the conditions required by the next, until the vegetation reached a stable configuration, or “climax.” Based on his observations, Clements proposed that not only the Great Plains grasslands but the entire living world was sustained by these self-organized, internally motivated processes of renewal.

Clements’s prairie-inspired theory of “community succession” made a stir in the intellectual capitals of the world. And it was there, in London, England, that his intuitions were eventually brought to a new stage of development. The concept of the “ecosystem”—the idea that the Earth operates as a series of self-organized complexes in which all components (both living and nonliving) are linked—was first advanced by British ecologist Arthur Tansley in 1935, in a self-conscious attempt to marry the study of nature with advances in math and systems theory. Suddenly, the young-and-still-somewhat-woolly-headed science of ecology, which had heretofore made do with hazy notions of “relationships” and “community,” could gird itself in the vocabulary of the physical sciences. Instead of a bewildering clutter of sensations, the living world had become a “complex, adaptive, open, nonlinear system,” complete with “feedbacks” and thermodynamic “fluxes.”

Yet for all this new exactitude (which has served the science well), the idea of the ecosystem has proven reassuringly resistant to precise definition. As Tansley himself acknowledged, “the systems we isolate mentally are not only included as parts of larger ones, but they also overlap, interlock and interact with one another.” The task of charting these overlapping and fluid realities— of acknowledging the differences between particular localities without denying their interconnectedness—remains a major preoccupation of ecologists. It is a challenge that, over the last thirty years, has inspired a continent-wide spree of “ecological land classification” and mapping. At its heart, this is an attempt to see beyond the human impacts of the last few centuries and uncover the enduring components of the environment (climate, soils, landforms, vegetation, and so on) that make one part of the continent biologically different from the next. Although we cannot go back in time and view the wild prairie in full bloom, we can attempt to identify and assess the factors that, over the long term, made them what they are or, at least, what they once were.

Ecological mapping began in the 1960s and 1970s as a relatively straightforward attempt to examine the relationship between natural vegetation and climate. Nowadays, however, with satellites to assist with mapping and computers to do the grunt work, the possibilities have spiraled. Instead of being limited to single variables, researchers can now consider the interplay among dozens of different ecological components all at once, factoring in everything from climate to geology, hydrology, physiography, soil chemistry, vegetation, species diversity, and where relevant, human effects on the environment. Yet even at this high pitch of sophistication, scientists have not been able to pin the living world neatly to the wall, sure that they have mapped its subtleties once and for all.

Rough fescue

Over the last decade, the ecological regions of the Great Plains have been mapped in different ways by different agencies, whether in broad strokes as part of continentwide research or more minutely, state by state and province by province. One result of this effort is a set of maps created under the joint authorship of the World Wildlife Fund Canada and its counterpart in the United States, the wwf–U.S. Seen through the lens of these organizations, the Great Plains grasslands come into focus as a mosaic of fifteen eco-regions. The Aspen Parklands ecoregion, for example, lies across the midriff of the Prairie provinces (Alberta, Saskatchewan, and Manitoba) and provides an interface between the boreal forest and the open plains. Rising in the north as a closed poplar woodland with occasional stands of spruce, it gradually unfolds into a rolling grassland dotted with aspen groves and dominated by various spear-grasses, wheatgrasses, and most notably, fescues.

Because of the predominance of fescues in the Aspen Parklands, the region is sometimes known as a fescue grassland. The same term is also applied, for the same reason, to the community of plants found in the Foothills Grasslands. Located on the undulating slopes at the foot of the Rocky Mountains, this ecoregion is dominated by rough fescue, together with lesser quantities of June grass, speargrass, wheatgrass, and various flowers and shrubs.

East of the foothills and south of the Aspen Parklands lie two ecoregions with subtly different characteristics. The Northern Mixed Grasslands takes its name both from its northerly location and from its characteristic mixed— which is to say, mixed-height—cover of grasses. Here, the sparse, tufted vegetation of the foothills gives way to a groundcover of ankle-high grasses, notably blue grama, intermixed with an overarching canopy of knee-high stands, including various spear- and wheatgrasses. As this mixed grassland flows southward, the canopy of taller, midheight grasses gradually thins out, and the overall height of the vegetation diminishes. This transition from mixed-to short-grass prairie continues to the south in the Northwestern Short/Mixed Grasslands ecoregion.