Mike Blake / Reuters

Among the shortage alarms of the 1970s—energy, strategic minerals, meat, coffee, timber—one seemed particularly gloomy. The United States was said to be running out of itself. Land was being paved over at an unprecedented pace, with tillable soil, the source of the country’s agricultural bounty, the hardest hit. Shortly before leaving office, in 1981, Secretary of Agriculture Bob Bergland declared that scarcity of land would become “a driving force behind the rate of inflation.” Gus Speth, then the chairman of the Council on Environmental Quality, warned of no less than the “destruction of our rural landscape and heritage.” Typical headlines ran “THE PERIL OF VANISHING FARMLANDS” (The New York Times) and “FARMLAND LOSSES COULD END U.S. FOOD EXPORTS” (Chicago Tribune). Reagan’s first Secretary of Agriculture, John Block, took up the cry, calling the disappearance of farmland a “crisis in the making.”

The predictions of impending land catastrophe were based primarily on the National Agricultural Lands Study (NALS), the work of a federal task force created in the second half of the Carter Administration. NALS widely promoted two fearsome conclusions: first, that the annual rate of urban expansion had tripled since the 1960s, from about one million acres paved to about three million acres, and second, that a high proportion of the “converted” acreage was prime cropland—a million acres of the country’s best soil being “permanently lost to agriculture every year in the U.S.”

Just where was this land going? Nowhere, it turns out. In 1984 the Soil Conservation Service (SCS), the branch of the U.S. Department of Agriculture that supplied the statistics on which the NALS findings were based, issued a new report that in effect retracted NALS. Estimates of the country’s paved acreage, the new report said, had been “markedly overstated.” The rate of urban growth, it now appears, has not changed significantly since the 1950s, and the acreage available to farmers is either stable or actually increasing (though improvement of previously unusable soil). Even the former NALS research director, Michael Brewer, criticizes the task force’s conclusions, saying that a “tendency to trumpet and exaggerate” has “led to a lot of mischief.”

The canceling of this Mayday call has not occasioned even a small fraction of the media or political attention paid to its issuance. And since 1981 many state and local regulations have been passed to safeguard “vanishing” land, with a shocking shortage often cited as their justification. How could a major federal study have been so far wrong on a basic assumption? Why did a prediction of doom find such a receptive audience, whereas word that things are under control has been greeted with a yawn? The sequence of events is a case study in how Washington loves a crisis.

Despite the best efforts of subdivision developers, urbanization has overtaken only a fragment of America’s land. The most recent statistics from several sources indicate that “build-up” land—cities, highways, airfields, and so on—totals 47 million acres. This is equal to an area about the size of Missouri, or two percent of our 2.3-billion-acre country.

Now, to someone living in Manhattan, one million acres, may sound like the circumference of the Crab Nebula. In fact, it is equal to about one twenty-fifth of one percent of the country’s land inventory. If every man, woman, and child in the United states were given an entire acre to live on, only ten percent of the U.S. land mass would be taken. Even if the largely uninhabitable state of Alaska, which contains 16 percent of U.S. land, is subtracted, the proportion of urban area to farm, forest, desert, and prairie remains low. While it would be possible to run out of land, this prospect seems far distant.

Nevertheless, during the 1970s there were reasons to be wary. U.S. agriculture was in a boom cycle; demand for food exports was rising, and if it continued to rise at the 1970s rate for a long time, a significant increase in cultivated acres might be require. Meanwhile agricultural land prices were shooting up to an extent that didn’t seem to be justified by the profits to be made selling crops. Scarcity can cause price increases: maybe, some puzzled observers concluded, land is scarcer than we think.

It was in this climate of opinion that the Soil Conservation Service conducted two consequential studies. The first, the 1975 Potential Cropland Study, attempted to estimate the rate of urban conversion, using a sampling of changes in some areas surveyed in 1967. The second, the 1977 National Resources Inventory, attempted to estimate how much agricultural land existed, using a larger sample. These two studies would later form the statistical base for NALS, which began in 1979 with a status similar to that of a presidential commission. Unfortunately, they were “misquoted, misunderstood, and in the view of several critics, misconceived,” according to Rutherford Platt, a University of Massachusetts geographer who initially supported NALS, writing in a recent issue of The Professional Geographer.

To simplify a ponderously technical story: the local SCS employees who collected data for these two studies, called district conservationists, were given insufficient time in which to be thorough and were allowed to use guesstimates. Classifications for large areas of land were required to be determined by recent U.S. Geological Survey maps or aerial photos, but classifications for smaller plots could be arrived at by taking a random sample and extrapolating from it. There was a dispute over how to classify lands that were “agricultural” but not used in farming, such as forests and everglades. Definitions had changed since the 1967 study—especially the key definition, “prime cropland,” referring to flat, drained soil.

Some assumptions had been changed as well. In 1967 SCS officials considered farmland located in urban regions to be farmland. In 1975 they decided to consider it urban. Farmland near cities is more common than might be guessed; this change alone had the effect of making a huge amount of land “disappear” overnight. Projected from the samples to the entire country, it created a paper crisis.

“The surveys were not comparable, but if you merged them together, they seemed to produce a rapidly accelerating rate of urban conversion,” says H. Thomas Frey, a geographer from the Department of Agriculture’s Economic Research Service, who participated in some NALS research. Indeed, the 1975 study seemed to show that urbanization had doubled since 1967, from approximately one million acres a year (a rate that had held relatively steady for decades) to two million acres a year. And the 1977 study showed it increasing by another 50 percent, to three million acres a year—a tripling overall—in the two years thereafter.

“Three million acres a year” became what detractors and proponents of land preservation alike called the magic number: impressive, ominous, nicely rounded. NALS was created in response, at the urging of Representative James Jeffords, of Vermont, who had been trying without success to pass a national land-preservation law; one of his aides, Robert Gray, was made director of the project.

Among NALS’s first acts was to issue a booklet titled “Where Have the Farmlands Gone?”, which contained statements like “Ten years from now [1979], Americans could be as concerned over the loss of the nation’s prime and important farmlands as they are today over shortages of oil and gasoline.” Gray mailed letters offering to send “a dozen, a hundred, or a thousand copies” of the booklet to anyone who would distribute them to “neighbors, students, local government officials, religious and civic groups.”

By assuming that the magic number was true—rather than investigating to find out if it was—NALS effectively arrived at its conclusion before work began. Early NALS publications raised the level of alarmism by assuming that all “agricultural” land was prime cropland, the most valuable kind. Actually, “prime cropland” makes up only about 17 percent of agricultural land (the balance is forests, grazing land, and so forth).

By the time its final report was published, in 1981, NALS had clarified the jumble over prime land. The three-million-acre figure remained, however, and formed the centerpiece for the project’s recommendations, which included a presidential or congressional declaration that farmland should be preserved, federal subsidies for shifting development away from rural areas, federal assistance for state and local governments to devise more-stringent zoning regulations, and a truly dire prediction that within the next twenty years at least 84 million more acres of tillable soil—a land area exceeding the size of Montana—might be needed to maintain agricultural production.

That there could be a debate over how much of the United States has pavement on it and how much doesn’t may seem incredible. After all, the land is finite, and evidence of how land is used is not exactly concealed. But, according to Michael Brewer, who worked on the report, “land-use statistics have always been contentious and probably always will be.”

The great size of the country makes on-site surveying prohibitively expensive. Site surveys are generally done only when property changes hands, and not always then. Aerial photography is thought to be the most efficient technique for gathering accurate land-use information (it’s much faster than indirect means—for example, analyzing local government records), but a complete survey of the United states using aerial photos would still cost many millions of dollars. And because land uses change, even if a fleet of reconnaissance planes started off in Maine to crisscross every square mile of the country, by the time they reached Hawaii the Maine findings would no longer be valid. So figures for a subject like land use, which in theory could be definitive, for practical purposes must entail estimates. This does not, however, prevent them from acquiring the weight and might of statistics, which often come to be treated as though they possessed greater wisdom than the people who made them up.

Were there clues that the three-million figure was exaggerated? Thomas Frey thought so; he argued behind the scenes that NALS was using faulty data. Employing statistical techniques preferred by geographers, and drawing on data he considered more reliable, such as Census Bureau numbers, Frey estimated that the rate of urban growth was up slightly in the 1970s, from 1.1 million to 1.3 million acres annually. Frey’s efforts went for naught; the NALS staff froze him out.

“Their studies were all designed to support what they had concluded at the outset,” Frey says. “NALS was a political document, and [the authors] did not want to hear form anyone who said that the sky was not falling.” Robert Boxley, a Department of Agriculture economist who also worked with the NALS task force, told me, “The NALS premise was that, in effect, we were running out of land. NALS was looking for numbers to justify the premise.”

After NALS came out, the technical journal Land Economics assigned William Fischel, an economist at Dartmouth and the author of the textbook The Economics of Zoning Laws, to review the study. Fischel found in the NALS data many assertions that academics politely call “counterintuitive.”

Connecticut, for instance, was listed as having doubled its urban land area, even though its population growth had been below the national average. A few states showed negative urban growth, which is nearly impossible—a premise of the land-preservation movement being that pouring concrete is irreversible. (It is physically possible to rip out concrete and restore developed land, but this is hardly cost-effective. By the same token, it should be borne in mind that most prime farmland is not a natural occurrence. Much of the U.S. heartland was swamp before it was drained and flattened; California, western Nebraska, and Arizona were hostile to agriculture until they were irrigated. It is estimated that up to 266 million unused acres in the United States could be transformed into cropland, if farm prices justified the expense.)

A U.S. Geographical Survey geographer named Richard Kleckner was bothered by the data that NALS was using, and in 1980 he compared NALS assumptions about four states with current USGS aerial photographs of those states. In three of the four states, Kleckner found, the NALS numbers for urban land were much too high—in one, Florida, the difference was 74 percent.

The economist Julian Simon was also doubtful of the claims about land. Now known as the author of The Ultimate Resource, Simon was then a business-administration and economics professor at the University of Illinois in Champaign-Urbana, the buckle of the Corn Belt. In 1981 officials of the Illinois Farmers Home Administration the Champaign County Soil and Water Conservation District, the county Regional Planning Commission, and other local agencies began declaring in urgent tones that 30,000 acres of Champaign County had “disappeared” to urbanization between 1960 and 1978. Editorials in local papers expressed horror. Simon checked and found that the total number of urban acres in Champaign County was 30,000.

Simon called the officials who had used the figure, asking for their source, and eventually backtracked to a year-old issue of a newsletter from the Illinois Department of Agriculture’s Division of Natural Resources. The 30,000-acre number had been based, Simon discovered, on a comparison of farm tax-assessment figures for 1960 and 1978—by a DNR analyst who apparently hadn’t known that assessment formulas had been changed in the interim. Read at face value, the tax data portrayed Illinois agriculture as grinding to a halt during the height of the 1970s export boom. The DNR, Simon was told, had discovered the error and repudiated the figure almost immediately after publishing it—but by then it had taken on a life of its own. Around the same time, Illinois Governor James Thompson issued, to considerable fanfare, an executive order on the “preservation of Illinois Farmland.”

Simon became interested in NALS, as well. Along with Fischel, Frey, Boxley, and Brewer, he wrote a number of articles for small-circulation specialized journals protesting that the three-million-acre figure had no support. Somehow the word did not filter into the general press, however.

NALS, in fact, was released at the very time farm surpluses were reaching record highs. The same newspapers that carried reports of the shocking loss of farmland also carried stories of silos overflowing with more food than anyone knew what to do with. And the stories generally failed to note that even if available cropland were decreasing, this would not necessarily mean a reduction in food supplies, because farm productivity per acre has steadily increased. Thus, in effect, technology can increase the amount of land the country possesses (a point Simon liked to make in his NALS critiques), by freeing acreage now under cultivation for other uses, including what planners call “amenity value”—parks, green space, and preservation for its own sake. A recent report from the Office of Technology Assessment predicts that by the end of the century there will be another revolution in agricultural productivity, perhaps allowing as much food as is grown in the United States at present to come from half as many acres.

The Soil Conservation Service conducted a new National Resources Inventory in 1982, taking pains to use better techniques and a larger sample over a longer time. When the 1982 inventory concluded that earlier estimates had been “markedly overstated” and put the urban land total at 47 million acres, not 65 million acres, as NALS had assumed, few news organizations gave the story paly. “I saw very little recognition of this anywhere,” Robert Boxley says, “and I still see that three-million figure floating around. It’s amazing, the charmed life it has.”

The 1982 inventory also showed that cultivated acres had continued their recent trend of gradual increase, from 395 million acres in 1967 to 413 million acres in 1977, when the “disappearance” scare started, to 421 million acres in 1982. (This is the most recent figure; another inventory is scheduled for 1987.)

There was a quick and easy way to double-check the figures all along, William Fischel notes. Urban growth could not have tripled in a single decade without a phenomenal surge in the rate of construction activity having occurred as well. But construction-industry figures for the period show only moderate increases, in line with those of previous years. “The three-million figure was out the window from the very start,” Fischel says.

Robert Gray, now a senior associate of the American Farmland Trust, a nonprofit preservationist society, stands by the magic number. “If anything, I think it’s too conservative,” he says. “But even if it is wrong, the ultimate proof is that the people at the state and local level, who have to deal with specifics of land use, consider urban conversion a serious problem. When it’s your town, an abstract argument about statistics doesn’t mean much.”

Gray says that since 1980 more than 300 counties have enacted new agricultural-zoning laws, that six states have created special agricultural-district laws, and that twenty-eight states have passed “right to farm” legislation exempting farmers from noise ordinances and similar residential restrictions that create disputes whenever suburban expansion begins to reach a rural zone. In 1980 Congress also enacted a “conservation easement” that gives farmers tax breaks in return for donating land to trusts that require the land to be used only for agriculture in perpetuity. About two million acres have since been placed in conservation easements (some of them held by Gray’s organization).

Of course, the fact that communities are passing land-preservation laws may indicate only a self-fulfilling prophecy—a false alarm taken seriously. It may also indicate other factors at work. William Toner, a professor at Governor State University, in Illinois, who is studying the new land0use laws, says, “The interesting thing about this movement is that it has no leadership and no coordination. There’s no clear pattern among those who are passing the new laws, and no ideological consensus. The only common denominator is a strong desire to protect the rural environment.”

The desire for preservation as an end in itself was written between the lines of NALS. “Land scarcity is a proxy for other issues,” Brewer, the NALS research director, says. “When the false arguments about food production and urbanization are peeled away, what people are really saying is that they like to live in a rural setting and they don’t want other people coming in.”

Or, as Fischel puts it, “Exclusionary zoning is the major purpose behind land preservation. People who pass these laws are thinking, We’re here. Now how do we pull up the drawbridge? State courts throw out zoning when it is obviously biased against the poor. So the idea that land uses must be frozen in place in order to prevent a national agricultural disaster is a convenient rationalization for exclusion, one that allows you to talk about something other than the real issue. I’m not saying that people who support land preservation on the theoretical level are insincere. They’ve just stumbled onto an issue that appeals to people on the local level for unrelated reasons.”

Land-preservation laws may not always be designed to protect elegant views and quiet sunrises in affluent communities. Toner says that the laws are being passed in poor communities as well as rich ones, places where there is no influx of yuppies and CEOs. Interest in preserving the amenity value of land thus appears to cut across income lines. And the more popular land preservation becomes, the more keenly its two central conflicts will be felt.

First, the perpetual planners’ dilemma: if you put people together it’s inhuman, and if you spread them out it’s sprawl. Skillful dodging between the horns of this dilemma can make virtually any land use sound bad. Even if a resource is plentiful, it should be used wisely. Given that new homes and factories must be built, and that while it may be geographically possible, it is not economically possible for everyone to live in a rambling restored country house powered by solar energy, compromises between the environment and the cement mixer cannot be avoided.

Second, at some point the right to shape one’s own community begins to infringe on the rights of others. Were there no legal limits to zoning power, it’s a safe bet that many communities—and not just affluent ones—would quickly pass laws effectively banning outsiders and nearly all development. The main legal restrictions on zoning laws are that they must be constitutional (not intended to discriminate, to impede travel or commerce, and so on) and that they must serve a reasonable public purpose. Clearly there is a public benefit in having factories in one part of town and homes in another part. But what about, say, requiring that homes be surrounded by at least ten acres of open property? This may serve a private benefit (making the homes more pleasant and valuable for their owners) but not necessarily a public one.

Yet it’s equally true that there is public benefit in preventing development from occurring in a way that detracts needlessly from the natural heritage. (Even though this is the most individualistic of societies, the clause of eminent domain gives government the final say about land use.) This is what justifies putting some land beyond the reach of bulldozers, in state and national parks, and may justify some tightening of zoning laws to ensure that development makes sense. Amenity value in land use is a valid public goal. But it should be sought after honestly, not through proxy arguments.

A test of how far zoning can go—both legally and in terms of common sense—is a “comprehensive land management” plan passed by the Oregon legislature in 1973. It essentially confines future urban expansion in Oregon to places where cities already exist. If the land-management plan stands up in court, and turns out not to stifle economic growth or grant an exalted status to the state’s present rural property holders—big ifs—tis law could serve as a model.

In retrospect it seems clear that “vanishing land” became a crisis because a crisis served media and political interests. The press got a shocking story to report—one that made good television, since expanses of rural land are photogenic, and one with broad appeal, since who could be in favor of paving over the heartland? Farmers, who because of their dependence on government are predisposed to cry “Woe is me,” got a new item for their list of complaints. Farm-state politicians got something to bluster over, followed by a “solution” to take credit for—the new local laws and the farmland Protection Policy Act, passed in 1981. (The act is basically for show, having only weak provisions.) Preservationists got an official government study to back their claims, which stays official even if its findings are later questioned. Affluent property holders got another weapon or their legal arsenals. Washington in general got to satisfy its primal urge of the 1970s, which was to declare a crisis.

Washington’s primal urge in the 1980s, however, is to declare that everything is fine and should be left alone. “I’ve heard it said that the world is split into two kinds of people,” Boxley told me. “There are the pessimists and the ecologists, who feel you have to frighten people into changing their ways. And there are the optimist and the economists, who say there’s no problem. If you look at history, the tendency is to overestimate demand growth and underestimate supply response. So, based on that, you would see that land conversion is no problem. But then, history is full of exceptions.”

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