News Feature
Deep changes taking root in u.s. agriculture Rising costs of fuel and of fertilizer, pesticides, and herbicides are forcing farmers to weed out inefficient practices; increasing support for plant research is expected to bear fruit in the future With the growing season now well under way, American farmers are beset with traditional farm concerns over rain, weeds, and insects. But added to these again are the concerns of the past few years with rising costs of energy and chemicals. And these newer concerns are affecting the way farmers are going about their work. It's a comfortable and oft-quoted statement that one American farmer can feed 50 people all by himself. The statement is true enough—on the surface. The system is incredibly robust. To Americans it seems only natural that the nation's chief dietary problem is not malnutrition, as it is in much of the rest of the world, but obesity. So bountiful is the soil of the Midwest that people actually are using edible grain—in its fermented form, ethanol—as auto fuel. On the global scene, some 65% of the grain that is exported in the world is exported from the U.S. When the harvest is bad in the Ukraine, as it often has been of late, even the Kremlin must look to the grain elevators of Duluth—a fact made vivid by President Jimmy Carter's 1980 embargo on the sale of grain to the Soviet Union, and by the recent controversy over the Reagan Administration's lifting of that ban. Agriculture has long since entered the realm of geopolitics. On the other hand, that fabulously productive American farmer is utterly dependent on petroleum and petrochemicals to supply him with diesel fuel, fertilizer, pesticides, and herbicides. Given the U.S.'s dependence on imported oil, and the vagaries of the Organization of Petroleum Exporting Countries and mideastern politics, there is cause to wonder how long the system can continue as it has.
Agricultural practices in the U.S. in cause the farmer himself depends fact are undergoing slow but pro- upon large inputs from petrochemifound changes, changes that will have cals, machinery industries, and comequally profound effects on how and mercial services. A more realistic how much agricultural chemicals will statement is that about one person in be used in the coming decades. Heavy five in the nation's work force is indemand for grain exports, environ- volved in supplying food in the mental concern over pesticides and American system." About 17% of the nation's fossil herbicides, increased use of biomass energy, new crops created by genetic energy goes for production (including engineering and advanced breeding shipping), processing, and for preptechniques all will continue to play a aration of food, with about one third part. But for the present, nothing is allocated to each activity, Pimentel having so great an impact as the in- continues. For comparison, automodividual farmer's efforts to cope with biles burn about 25%. On the production end, by far the the rising costs of energy and petrolargest fossil energy inputs are for fuel chemicals. Last year CRC Press published its and nitrogen fertilizer. The numbers "Handbook of Energy Utilization in vary greatly between locations in the Agriculture," edited by Cornell Uni- country and even more from crop to versity entomologist David Pimentel. crop. (Alfalfa, for example, is a le"Currently, the high yields with rel- gume that fixes nitrogen on its own atively small inputs of manpower are and doesn't need fertilizer.) Fairly associated with mechanized agricul- typical, however, are the handbook's ture and are due essentially to ample estimates for corn grown in southern supplies of inexpensive fossil energy," Minnesota. The fossil energy input is he writes in the introduction. "The about 6.5 million to more than 7 miloften quoted statistic that one U.S. lion Btu per acre; the energy content farmer feeds about 50 people [is] an of the final product is just under 61 oversimplification of the facts, be- million Btu per acre. Liquid fuel and
This article was prepared by former C&EN West Coast bureau head M. Mitchell Waldrop, now with Science, Washington, D.C. Nitrogen fertilizer, costly In terms of fossil fuels, being applied to corn June 1, 1981 C&EN 23
News Feature
Aerial spraying of fungicide protects orange grove from Infestation
nitrogen fertilizer account for just under 40% of the input apiece, and transportation of materials to the farm accounts for 11%. Filling out the balance are the energy costs of seed production, pesticides, and phosphorus and potassium fertilizers. "Rising energy prices have not changed practices so much as they have changed how the inputs are managed," Pimentel tells C&EN. "When nitrogen was quite cheap, less than 10 cents per lb, growers would apply it in the winter, when there was lots of surplus labor and equipment. Nobody cared that it was soluble and that lots of it was lost in the spring runoff. "But now the price is up by a factor of four or five, so you apply it during the spring and summer when the crops can make use of it," he says. "Even then nearly half of it leaches away or is oxidized by microorganisms. People are working on ways to prevent the loss and improve the timing, but again, there's a trade-off with the cost of machinery and labor." Parenthetically, Pimentel doesn't lend much credence to the idea that heavy fertilization is somehow harming the soil, or is lowering the nutritional value of food. "I haven't seen any good scientific evidence," he says. "Ammonia is made in nature, so how can it be bad for the soil? Again, all analyses of the nutritional value of food show little or no effect. Most of the organic matter in plants is made from sunlight, water, and carbon dioxide, after all. Plants also take some trace metals from the soil, and a few have microorganisms that take nitrogen from the air. For the rest we 24
C&EN June 1, 1981
have to replace what we are taking out every year, which implies fertilizer, which implies energy." The rising cost of energy on the farm, compounded by similar increases in the processing and transportation of food, shows up most obviously at the supermarket cash register. But there are also second-order effects that can have a profound impact by putting an economic squeeze on the individual farmer. "It's the transportation costs that have risen the most, and hurt the most," says Eric Thor, agricultural economist with the University of California, Berkeley, cooperative extension. "People think that it just affects the cost of food, but the big effect is on market structure, where the food is grown, and where it is sold." California dairymen, for example, used to haul in alfalfa hay from Idaho. But now that the cost has risen to $35 or $40 per ton, he says, it pays to grow the hay locally. So Idaho is losing a profitable crop. The Californians themselves, on the other hand, are hurting badly in Vegetable crops (the state produces 25% of the fresh vegetables in the U.S.). Two years ago, Thor points out, a truck could haul lettuce from Salinas to the East Coast for about $1800 per load, or about $2.00 per carton. Add in the cost of production, roughly $4.00 per carton, and it was still competitive with $6.00-per-carton lettuce from New Jersey and Maryland. Today, however, the transcontinental shipping costs have more than doubled. So the California growers, says Thor, are losing out. Energy prices also have driven up
the cost of food processing, says Thor. The cost of canning, for example, has risen by a factor of almost five since 1972. So the market for canned goods has fallen. Vegetable crops can be cut back easily enough, but it's hard to reduce volume very rapidly on fruit tree crops like peaches, pears, and apricots, he points out. So the growers try to maintain their orchards from year to year while the prices plummet. "The individual farmer knows what's killing him," says Thor. "It's the transportation costs and processing costs. These have several times more effect on the farm than the production." On the other hand, if the individual farmer can't do much about the first two, he certainly can do something about his own costs. "Farmers are a very innovative group of people," Thor says. "Most of them are way ahead of the universities on this." With irrigation, for example, farmers don't just go out and kick a few clods anymore. Growers are putting instruments in the ground to determine just how much water they need and when they need it. They are installing smaller pumps, matching capacity more closely to demand. With pesticides—and with so many restrictions on their use in recent years—growers are moving more toward the use of commercial spraying services. Because California law requires that a sprayer pass certain exams, Thor says, a network of independent pest management consultants—some even have Ph.D.'s—has arisen to provide the services. "With commercial sprayers you don't spray unless you absolutely have to," Thor says. "When you did it yourself, you sprayed regardless." Richard Norgaard, Thor's col· league at the University of California Giannini Foundation of Agricultural Economics, Berkeley, points out that there has been a fairly steady rise in the use of consultant services over the past 20 years. Today they have about 20% of the pest control market in such important California crops as cotton and grapes. Norgaard also believes that the number of practicing consultants offers the best measure of how much the rather abstract idea of integrated pest management is actually taking hold in the field. "Certainly the university professors of entomology don't think of consultants as high-powered practitioners" of integrated pest management, he says. "But they are highly competent and in good touch with the universities."
The term "integrated pest management" wasn't coined until the early 1970's. The basic concepts, however, can be traced to University of California entomologist Charles W. Woodworth, who was advocating an ecologically based pest management approach as long ago as 1896. The Berkeley campus has remained a stronghold of such thinking ever since; when chemical pesticides swept the market in the 1940's and 1950's, the agriculture school there was one of the few in the country to keep up the study of biological controls. In its modern form, integrated pest management is a melding of both approaches. A consulting service, for example, might carefully monitor a field to keep track of pests and their natural enemies, and then spray only when the pests threaten to get out of hand. The consultant might recommend intercropping—alternating rows of different crops on the same plot—to slow down the spread of any one type of pest. A change in the time of planting might avoid the most destructive phase of an insect's life cycle. The solution might even be as simple as cleaning up old shells and other debris from an almond orchard to take away winter cover for the navel orangeworm. The consulting service usually is provided at a fixed fee per acre, says Norgaard. For crops like cotton that come in big, uniform fields, the fee might run $4.00 to $5.00 per acre; for higher-value crops in smaller fields, $25 to $30 per acre. But that's still a savings, he points out, because pesticides cost up to $100 per acre—and a professional consultant can decrease pesticide use roughly 50%. So why isn't everybody using the technique? "Three dissertations later we still don't know," Norgaard laughs. He and his students have found that integrated pest management users tend to be a little older, a little more experienced, to have stayed in a crop longer, and to be more adverse to risk—all contrary to expectations. "Perhaps it's because the consultant is providing information," he says. "Information offsets risk." Pimentel, however, lists a number of practical problems with integrated pest management. In the first place, the technology is far more sophisticated than a straightforward application of chemicals, he says. You need to monitor each pest and its natural enemies. Then you have to know the threshold density of the pest that will cause a significant crop loss, plus the
Water caused severe erosion on this steep slope In Washington
density of natural enemies that will control the pest. Next, you have to project the infestation based on past data, including climate data. Finally, you have to predict the outcome of your intervention. Once all that is done, Pimentel continues, there's still a bit of risk involved: If you're right on the margin you could get an outbreak anyhow. So you err on the side of pesticides. Then there are the psychological factors. "If you spray," Pimentel says, "then at least you tried, you did something, you can see the little buggers falling to the ground and squirming. With integrated pest management you have to just sit there, depending on natural enemies you can't see. It's nerve wracking. Besides, you've got $200 per acre invested in your corn already, so another $6.00 or $8.00 to treat for cornworm sounds like a pretty cheap insurance policy. And if you pay somebody $3.00 to $5.00 per acre to scout your farm, and he tells you that two thirds of it needs spraying anyway, that's not much of a savings." Finally, says Pimentel, there's a matter of salesmanship. There are a lot more pesticide salesmen than there are extension people. But integrated pest management is coming on nonetheless, Pimentel says. It's a prime example of the "systems management" theme now being sounded more and more often in the agriculture schools. One extension service now being offered by the University of Michigan, for example, is a farm-management software package that can be accessed by telephone hookup to the individual farmer's home computer.
Also, a good many farmers are feeling a genuine concern about the health and environmental problems of pesticide use—after all, they are the ones who have to live with these chemicals every day. And a prime advantage of integrated pest management is that by minimizing the use of pesticides it exposes a smaller percentage of the pest population and thus slows the buildup of resistance. "Worldwide, there are more than 400 species of insects and mites that now have some form of resistance," Pimentel points out. "The United Nations environmental program has called this one of the four major environmental problems of the world." In India, for example, DDT was first used for malaria control in 1950. Since people there were spraying only houses and such, he says, they exposed only a small fraction of the mosquito population. So the mosquitoes didn't build up any resistance, and the number of malaria cases plummeted. Then, the Indians started using DDT in agriculture. A large fraction of the mosquito population was exposed, the resistant strains multiplied, and the incidence of malaria increased from 100,000 cases in 1961 to 50 million in 1978. If economic factors have promoted more efficient use of energy on the farm and a more ecologically sound use of chemicals, the same cannot be said of its impact on erosion. "We are mining the soil," says Pimentel, "and we shouldn't be." Iowa had an average of 8 inches of topsoil when it was settled; today, 100 years later, it has 4. The U.S. as a whole now has 320 million acres routinely under June 1, 1981 C&EN
25
News Feature Plant biochemistry, molecular biology: once dormant research now growing Agricultural research, too, is feeling the influence of higher costs of energy and petroleum-derived chemicals as well as the limits of natural resources such as cultivatable land and water. For the first time, conservation is a real concern in American agriculture, and the concern is reflected in the goals of research as well as in the practices of individual farmers. Basic research into plant biochemistry and molecular biology was severely cut back in the U.S. and throughout the world in the mid-1960's. The biological sciences in general, with the exception of medicine, took a back seat to research in the physical sciences throughout the post-Sputnik period, says Gerald G. Still, chief scientist for plants and entomological sciences for the Department of Agriculture's Science & Education Administration. The consequence, he says, is lack of a fundamental understanding about basic plant biochemistry and molecular biology. "Compared with other biological systems or with the physical sciences, we just do not have the fundamental knowledge about plants," he says. This policy may be beginning to turn around, Still says. The past five years have seen steady, though modest, increases in funding for basic plant research within USDA. And the proposed budgets for next year include a more substantial increase in funding for this area. The result, Still says, is that groups to study new areas of plant research are now established and research results are beginning to appear. One area in which fundamental research is beginning to pay off is the study of the photosensitive plant regulator called phytochrome. First discovered in 1952, this polypeptide is an important switch that enables a plant to sense its environment and adjust its growth cycle accordingly. Phytochrome is involved in the control of many types of plant growth including flowering, branching, leaf formation, and seed germination. If its chemistry were well enough understood, it might be possible to use this switch to time a plant to grow when it would be most efficient for the farmer. Despite its obvious importance, much of the basic research into the biochemistry of phytochrome is just now being done. Lee H. Pratt of the University of Georgia, for example, discovered last year that phytochrome is a dimer, not a monomer as had been earlier believed, and that each subunit in the dimer has a photoactive site.
26
C&EN June 1, 1981
Since each phytochrome subunit can exist in two forms—one sensitive to red light and called Pr and the other sensitive to far red light and called P fr —the fact that the molecule is a dimer means that the dimer has three possible forms— Pr:Pr, Pfr: Pr, and Pfr: Pfr. At least two of these forms seem to be involved in seed germination for certain types of plants, including Grand Rapids lettuce, according to recent experiments conducted by William J. VanDerWoude, a plant physiologist at USDA's Seed Research Laboratory at Beltsville, Md. Grand Rapids lettuce, VanDerWoude explains, is "the white rat of seed dormancy research." He finds that chilling these lettuce seeds to 4 ° C then warming them to 20 ° C increases as much as 10,000 times the ability of red light to make the seeds germinate. This increased sensitivity seems to come in two steps, VanDerWoude finds, which he believes correspond to formation of Pr:Pffr and Pfr:Pfr complexes with receptors on the cell membranes of the lettuce seeds. The chilling, he thinks, changes the membrane lipids, which increases binding of these two forms of phytochrome, and that, in turn, triggers germination. Another promising area of current research involves culturing plants from pollen, rather than by more conventional culture methods that use the somatic, or tissue, cells of a plant. The technique is called anther culture because anthers are the organs that produce pollen in plants. The advantage of anther culture is that pollen, a germ cell, has only one chromosome from each pair that normally exist in tissue cells, explains Gideon W. Schaeffer, chief of USDA's Cell Culture & Nitrogen Fixation Laboratory at Beltsville, Md. Thus, there are no unexpressed genes in pollen cells that may unexpectedly turn up as expressed traits in future generations. "With anther culture," Schaeffer says, "what you see is what you get." The technique is still highly experimental, but already it has been used to identify a rice strain that has more of the essential· amino acid, lysine, in its seeds. Finding this hereditary trait by anther culture took about one third the time a similar search would have taken using conventional breeding techniques. And it could be done in one laboratory, rather than needing several acres of land. Another potentially very important advantage for anther culture is that it produces offspring with identical genetic makeup. When self-pollinated, these
offspring produce uniform seeds. Conventional breeding methods require backcrossing for many generations to get completely uniform seeds. Still another area of promising research for agriculture is genetic engineering. Ironically, genetic engineering's first applications to agriculture are likely to affect not plants, but animals. Work is already well under way, for example, to develop a much improved and less expensive vaccine against foot-and-mouth disease using recombinant DNA technology. Researchers at USDA's Plum Island Research Station on Long Island, N.Y., are working on the project under an agreement with the genetic engineering firm, Genentech. The USDA scientists are making synthetic portions of the protein produced by the foot-and-mouth disease virus, looking for the segment that turns on antibody production in infected animals. Once this segment has been identified, Genentech will use its expertise in producing animal proteins in bacteria to produce the protein in large supply. From a technological point of view, making foot-and-mouth disease vaccine is very similar to making insulin or somatostatin—other animal peptides that already have been made in bacteria using recombinant DNA technology. Such systems, in effect, turn bacteria, or some other suitable host, into protein factories that churn out vast amounts of the desired peptide, which then must be isolated and purified and used, like a drug, to treat another organism. One step further in the technology's development are experiments that would put a single useful gene not into a bacterium but into the actual organism that needs the peptide the gene represents. Thus, the organism, in effect, makes its own drug. Such experiments are clearly more complicated, since they require transferring a gene not into whatever host is easiest, but into the specific organism where it will be useful. Several plant systems fall into this category, and there is active research currently going on in a number of systems. Altogether, there are perhaps a dozen single gene transplant experiments that would be important for agriculture and might be carried out in the next three to five years, says Richard Meagher, assistant professor of molecular and population genetics at the University of Georgia. Meagher is one of a half-dozen or so recombinant DNA researchers in the U.S. who are working specifically with plant systems.
Genetic engineering techniques may soon find applications in agriculture 1981-85
1985-89
1990 +
Techniques to make protein "factories" Rennin Casein Animal growth hormone Foot and mouth vaccine Blue tongue vaccine Methanol-eating bacteria Bacteria using other feedstocks Amino acids
Now
Antibiotics Anabolic steroids Pesticides Techniques that modify whole organisms Pesticides Pesticide-resistant cultures Cloned livestock Gasohol fermentation bacteria Improved yeasts Cellulose-eating bacteria Salinization osmoregulation Antileaking gene to improve soybean nitrogen fixation Other nitrogen fixation improvements Cereals that can fix nitrogen Improvements in photosynthesis Note: Estimates based or>available scientific information and reasonable expectations of investments. Source: Policy Research Corp./Chicago Group Inc. study
Among the systems that Meagher thinks can be developed in the next five years are crop plants with the ability to cleave (and thus destroy) a particular herbicide. There are a number of broad-spectrum herbicides, he explains, that are degraded easily by common soil bacteria and thus present much less potential for environmental damage than the more persistent chlorinated aromatic herbicides widely used today. However, these compounds are not very selective—they kill crop plants as well as weeds. If the gene from bacteria that degrades the herbicide could be transferred to the crop plant, then it, too,
would break down the herbicide, leaving only the weeds to be killed. Key to genetic engineering changes in plants is an understanding of two steps in plant molecular biology that still are not worked out completely, Meagher says. To make any recombinant experiment work, researchers need to know exactly the DN A sequence they wish to transplant to a new organism. They must also know the appropriate "switch" for that organism—the sequence of DNA that also must be present so that the host's cell machinery will go to work on the new DNA and make proteins from it. In addition, there must be a vector, a
system that can carry the foreign genetic information into a new organism without being destroyed by that organism's immune system. For animal systems and bacteria several switches and vector systems have been worked out, but for plants these systems are still being developed. Beyond inserting a single "foreign" gene into a plant and having it function is the much more complicated task of inserting a whole collection of genes that will all work in concert to give the plant an entirely new and beneficial trait. This is the task that faces experimenters who want to make cereal plants fix their own nitrogen, for example, or improve the photosynthetic system of certain valuable, but energy inefficient, crops. Such projects are called "blue sky" by most analyzers of the potential for genetic engineering in agriculture. They may be possible someday, but there are many hurdles of fundamental cell biology that must be gotten over before the systems will be well enough understood even to know whether such a transplant is feasible. In fact, many thoughtful researchers at USDA and elsewhere think "conventional" plant breeding experiments are just as likely as genetic engineering techniques to succeed in making this type of radical change in plant characteristics. But neither approach is just around the corner, researchers caution. "I think it's going to be a long time until corn fixes nitrogen," Still says. "But I think it will be a short time before we can teach plants to handle drought or resist insect attack." Genetic engineering may be useful in the near future in one type of nitrogen fixation work, however, according to the Chicago-based consulting firms Policy Research Corp. and Chicago Group. These two groups recently have completed an extensive and very bullish study of the potential for genetic engineering in agribusiness. Genetic engineering's near-term effect on nitrogen fixation may be to make soybeans more efficient nitrogen fixers by reducing the loss of fixed nitrogen that most of these plants suffer. About 2 0 % of soybeans grown in the U.S. contain the gene for an enzyme that prevents nitrogen gas from leaking out of the plant. Genetic engineering researchers hope to be able to transfer this "antileaking" gene to other strains of soybeans—a change that could increase the protein yield of soybeans more than 1 5 % . The Policy ResearchChicago Group study projects this gene transfer to be possible by 1987. Rebecca Rawls, Washington
June 1, 1981 C&EN
27
News Feature cultivation. The Department of Agriculture estimates that erosion is causing a steady drop in the productivity of that land equivalent to the loss of 1.25 million acres per year. The difference must be made up with more fertilizers, more pesticides, more petrochemicals, and more energy. "At the moment," Pimentel says, "we're taking out 1 inch of topsoil every eight to 10 years on the average. The thing is, we could easily slow erosion to the rate at which new topsoil is being created from the bedrock, which is about 1 inch per century under agricultural conditions." The techniques are very straightforward, he says, and have been known for a long time. The problem is that it costs money to put them into practice. For example, it would help to rotate crops more. Back in the 1930's, when the soil conservation service first was established, most of the corn crop was planted in rotation with other crops. Now, only 40 to 45% is planted this way because continuous cropping is economically more efficient. Yet erosion jumps 25 to 30% with continuous cropping. Contour planting and plowing are obvious things to do, says Pimentel. But the big tractors can't always turn fast enough. So especially on the larger farms there's a tendency for a reduction in effective contour planting. Terracing is also obvious—but expensive and time-consuming. A cover crop, planted after harvest, could protect the soil over the winter. But this takes money for seed, and anyhow, a lot of farmers plow in the fall to save the rush in the spring. Perhaps the ideal way to control erosion is to eliminate plowing en-
tirely. In "no-tillage agriculture," last year's crop debris is left on top of the ground as mulch, instead of being plowed under. Seed is covered with just enough soil to allow it to germinate. There usually is no further cultivation before harvesting. Weeds and other competing vegetation are controlled by chemical herbicides. Lime and fertilizer are added to the soil surface. University of Kentucky agronomist Ronald E. Phillips and his colleagues recently found that no-till reduces energy input into corn and soybeans 7% and 18%, respectively, without reducing yields [Science, 208, 1108 (1980)]. Moreover, it virtually eliminates soil erosion. The authors estimate that no-tillage methods will be used on as much as 65% of U.S. crops by the year 2000; it also may prove extremely valuable with the fragile soils of the tropics. No one denies, however, that notillage agriculture has some problems of its own. Pimentel, for example, points out that dead weeds and old crop debris shelter insects, so more pesticides are needed. Coolness and moisture under the debris also cause some seed to rot, so more seed is needed. Furthermore, not all weeds are susceptible to chemical control. In fact, Pimentel says that some farmers have abandoned no-till because of weed problems. "I'm all for no-till," he says. But the system needs further development. Pimentel takes a rather fatalistic view toward the prospect of erosion control. "There's a certain attitude of 'Get what you can out of the thing, and let other people worry about the future,' " he says. "But you can't blame the farmers. The capital in-
Capital Investment In even a small-scale farm Is huge 28 C&EN June 1, 1981
vestment in a farm is tremendous. And farmers are terribly underpaid; many of them operate so close to the margin that they can't afford to worry about maintaining the land's productivity 50 years from now." Not everyone is so pessimistic as Pimentel, however. Gordon Rausser, chairman of agricultural, and resource economics at Giannini Foundation, for instance, is cautiously optimistic that the price mechanism will ultimately act as a corrective. If soil erosion or other factors cause the productivity of the land to decrease, and if that is reflected in a lower price for the land, he says, then there is an incentive for maintaining it. On the other hand, productivity is only one factor in the price equation. People also buy land as an investment, as a hedge against inflation, especially when it lies in the path of suburban development. Moreover, government price support can drive up the price of produce artificially and thus the value of the land where it is grown. "If the loss in land values due to erosion is more than compensated by the other two factors," says Rausser, "then you're in trouble." Then the price of land will not fall, and over the course of a century or so the nation will find itself with a markedly less productive resource base. "If that happens," Rausser adds, "then you either learn to live with it, or else you have a powerful incentive to develop new technologies." The list of agriculture's problems could go on forever, it seems. There are worries about dwindling water supplies for irrigation, the effects of acid rain, and the recent plagues of drought. Both urban and rural Americans, ever reluctant to embrace land-use planning, are still paving over good farmland with subdivisions, shopping malls, and roads at the rate of a million acres per year. The nebulous political issue of large corporate farms vs. the small family farm still continues to simmer. But if the problems are real enough, agriculture's future in America is hardly so bleak as some have made it seem. The system is not in danger of imminent collapse. Indeed the predominant mood among university and government experts contacted by C&EN was one of optimism: that American agriculture, as energy-intensive, chemical-intensive and petroleum-dependent as it is, will adapt to the times; that the problems tend to be self-correcting; that the land will remain fertile and bountiful for a long, long time to come. D
