How Farmers 404
Affect Natural Many of our natural resources are either owned or influenced by farmers. Our 2.4 million Resources farms occupy over 900 million acres. Use of these lands influ- ences the appearance of our Na- By Sandra S. Batie tion's rur£d landscape, the qual- ity of our water and air, as well as the amount and tjrpe of our wildlife. In short, farms are an impor- tant part of the ecosystem we depend on. Not only do farmers influence our natural resources; the quality, quantity, and price of natural resources influence farmers' profits and ultimately their ability to continue in farm- ing. The farm sector is extremely diverse. A tobacco farm in the Virginia Piedmont bears little re- lationship to an irrigated vegeta- ble farm in California's Imperial Valley or to a dryland wheat farm in the Palouse country of Wash- ington State. A 65-cow dairy farm in New York may scarcely resemble a corporation-owned drylot enter- prise with 10,000 cows in Ari- zona. Still, each of these farms influ- ences and uses our Nation's re- sources: Agricultural land, water, energy, and wildlife.
Beliefs and Practices To a farmer, agricultural land is an input in a production proc- Sandra S. Batie is As- ess; land is needed to produce sociate Professor of crops or graze animals. Yet the Agricultural Econom- meaning of land to many farm- ics, Virginia Polytech- ers—perhaps most—transcends nic Institute and its production capacity. The land State University, Blacksburg. is a storehouse of wealth, a heri- How Farmers Affect Natural Resources 405
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Farming in the little relation- culture estimates that cropland United States is ship to an irri- erosion still occurs at an esti- gated vegetable extremely di- mated rate of 2 billion tons of verse. A dry- farm in the Im- land wheat perial Valley of soil a year. Although measuring farm, here in the California or to soil loss is difficult, widely used Palouse of a tolKLCCofarm tools show that four regions Washington in the Piedm.ont have severe water-caused ero- State, Jor in- of Virginia. stance, bears sion problems: 1) The Palouse and Nez Perce tage from the previous genera- areas and the Columbia Plateau tion, and a bequest to the next of western Idaho, eastern Wash- To many farmers, land is some- ington, and north-central Oregon thing special and precious. 2) The cropland soils of Ne- But farmers have to be busi- braska, Kansas, Iowa, and Mis- ness-minded to succeed. Thus souri farmers may hold strong beliefs 3) Uplands of the southern on the wisdom of land steward- Mississippi Valley, and ship and also farm in such a way 4) Cultivated areas in Aroos- as to cause considerable soil took County, Maine. erosion. Furthermore, almost 70 per- Erosion remains a national cent of the erosion exceeding 5 problem despite a half-century of tons per acre is on less than 8.6 government programs to combat percent of the total cropland it The U.S. Department of Agri- acreage. 406 Managing Natural Resource Systems
Erosion Can Cut Yields Erosion reduces the depth of topsoil, impairs the soil's capac- ity to retain water, and thwarts infiltration of water and air into the soil. As a result, soil erosion can ultimately reduce crop jàelds. But measuring yield reduc- tions due to soil erosion is diffi- cult because, over time, farmers may substitute increasing amounts of fertilizers or use other technologies to enhance the soil's natural fertility. Also, erosion effects on crop yields differ by soil type, crop, and management practices. Studies indicate, however, a re- lationship between erosion and reduced yields on many soils. If erosion has reduced the soil's water-holding-capacity, the root- ing depth available to the plant, or the water infiltration rate, adding fertilizer may not offset the yield-reducing effects. Erosion also affects air and water quality. Agriculture is con- sidered the main source for that part of the Nation's water pollu- tion that comes from diffuse (nonpoint) sources. Sediment in water runoff carries along fertil- izer residues, pesticides, dis- solved minerals (such as salts), and animal wastes (with associ- ated bacteria). Excessive sedimentation can clog navigation channels and can dirty drinking water, adding costs to rectify both, and can re- duce recreational opportunities. Also, in some areas, sediment is Soil erosion is timately reduce considered a crop yields. The rapidly filling inland lakes and problem be- sedim.ent in reservoirs. cause it can ul- water runoff is How Farmers Affect Natural Resources 407
no Less uj a Nation's water problem—con- pollution tributing sub- problems. stantially to the 408 Managing Natural Resource Systems
The Profit Factor For some tracts of land, con- If erosion reduces yields, servation may be economiced for water, and air quidity, why don't the farmer when the land is first all farmers practice conserva- cultivated. This might be true on tion? A major reason is many fairly flat land where the topsoil conservation practices do not is shallow but highly productive, pay for themselves. However, and the subsoil of substantially this is not because the practices poorer quality. In this situation, are ineffective. losing an inch of topsoil could Farmers can choose among reduce yields dramatically. Ero- many soil conservation tech- sion could be reduced inexpen- niques such as changing the sively if, for example, contour characteristics of a field's topog- plowing or residue retention raphy with terraces, planting were used. only the least erosive lands, ro- On other tracts where conser- tating crops, stripcropping, vation requires major land-mov- planting on the contour, retain- ing technologies to form terraces ing crop residues on the field and where straight-row, highly surface after harvesting, con- erosive cropping patterns can structing waterways, or using bring a high dollar return, pri- methods such as no-till. vate economics may dictate min- No-till is a technique that ing the soil. This is particularly eliminates almost all tillage, and true where the original topsoil is chemicals—rather than conven- very deep. tional plowing—are used to con- Other financial factors also in- trol weeds. On some croplands fluence the farmer's decision on this can reduce erosion rates 60 conserving soil. The lower the to 95 percent price of soil substitute, such as Many of the techniques are not fertilizers, the less likely the profitable, however, or not per- farmer is to conserve. Also, the ceived to be so. A business- lower a farmer's current net in- minded farmer—who must be come, the less likely he or she is competitive to remain in farm- to conserve, since substituting ing—is not interested in prac- future income for present in- tices that don't pay. Even a come is financially impossible. farmer with a strong land ethic While many soil conservation and a desire to practice soil con- practices may not be economical servation may find it financially investments for farmers, there impossible to do so. are exceptions, such as conser- vation tillage, contour plowing, Mining the Soil or Not and leaving residue on the field For the business-minded after harvest In some areas farmer, a decision to maintain, these practices are effective in improve, or deplete soil is largely reducing erosion and may even an investment decision. increase profits. How Farmers Affect Natural Resources 409
Farmers can choose among m.any soil con- servation tech- niques. On this cropland in southwestern Iowa, the farmer has cho- sen to plant on the contour and use conserva- tion tillage. These practices are effective in reducing ero- sion and in some areas of the Nation may even increase profits.
The Nation's policjmiakers 1962 low of 331 million acres, currently are considering mainly due to tremendous ad- changes in conservation pro- vances in yields per acre during grams to make them more effec- the I950's. tive in reducing soil erosion on Next there was a relatively sta- croplands. If incentives are pro- ble period when land used for vided so farmers will conserve crops averaged about 330 million the soil when and where it is ap- acres until 1972. Then the land propriate, substantial progress used for crops began to increase, can be made in both retaining reaching a new high of 391 mil- soil for future production and lion acres in 1981. improving water and air quality. Considerable regional shifts occurred in the use of cropland. Cropland in Use Over a third of the cropland de- Erosion influences the quality cline took place in the North- of our farmland. Another dimen- east, Southeast, Appalachia and sion is the quantity of farmland. the southern Plains. Other re- The amount of land in crops gions increased their cropland was relatively stable from 1920 acres. Recent rises were mainly through 1950, varying between in the Mississippi Delta States, 360 to 380 million acres. That the northern Plains and the was followed by a decline to a Com Belt 410 Managing Natural Resource Systems
Cropland in Actual Production
Land used for crops (millions of acres) 400
380
360
340
320-
300. 1910 1920 1930 1940 1950 1960 1970 1980
Source: USDA
Land Shifts Too Big? First, many communities enjoy These trends and changes the visual, cultural and financial have led many to question benefits from a viable agricul- whether too much land is being tural industry. Thus, some com- converted from agricultural to munities are willing to forego nonagricultural uses. benefits from whatever alterna- Numerous studies have been tive uses would have replaced made of the physical adequacy of agriculture in the region. There- our total cropland base relative fore they are interested in reduc- to future land requirements. ing the incentives for farmers to Many researchers concluded sell their land to non£igricul- there will not be land shortages turcdists. endangering food and fiber pro- Second, some farmlands have duction, although there may be unique characteristics for pro- some increases in the real costs ducing specialty crops—such as of production. cherries in the Great Lakes These aggregate statistics do States; citrus in the warmer re- not mean there should be no gions of California, Texas, and concern about conversion of ag- Florida; or wine grapes in the ricultural lands to nonagricul- coastal States. tural uses, however. If these lands are converted to nonagricultursd uses, replacing their production within the Na- How Farmers Affect Natural Resources 411
tion could prove expensive. More Much of the growth in water controlled environments might use has been concentrated in have to be provided, production the midwest, in States overlying costs could rise, or yields de- a vast underground lake—the cline. Furthermore, producing Ogallala Aquifer. Farmers have these specialty crops may give a used wells to raise water from region a unique cultural attrib- the aquifer to grow sorghum, ute the community wishes to corn, and alfalfa, some of which preserve. has been fed to cattle. However, the era of both low Agri-Urban Patterns cost water and low cost energy Thus many communities are appears over. Where farmers rely looking for techniques providing on ground water such as the farmers with incentives to con- Ogallala Aquifer, declining tinued farming. The search for ground-water tables coupled viable techniques is not easy with rising pumping costs make since frequently the communi- irrigation water more expensive. ties most interested in retaining High energy costs make it less agricultural land already have a attractive to pump surface water land-use pattern best described over long distances as in trans- as '*agri-urban." ferring water from one river Agri-urban is an intermixture basin to another. Also, western of farm and rural residential surface water sources are, for uses with no clearly defined the most part, already fully ap- boundaries for either use. This propriated, so new users in- usually means the demand for creasingly will have to bid water land for development and recrea- rights away from present users. tional purposes is strong, prop- This combination of falling erty taxes are high, and friction water tables and rising energy between neighbors over normal costs means, long term, that farm practices and suburban ground-water irrigation will de- uses is great Therefore, farmers cline. Farmers are adjusting to may have many incentives to sell higher irrigation costs by adopt- their land. ing water conservation meas- ures; still, the relative profitabil- Irrigation Use ity of irrigated farming to Use of water for irrigated agri- dryland farming has dropped. culture has tripled since 1940. This growth has been possible in Salinity Problem part because of low energy Increased irrigation not only prices for water pumping and impacts on water supplies, but Federal subsidies that have kept may result in rising soil and the cost of water low. Irrigation water salinity. Some researchers now accounts for over a fourth estimate that as much as 25 to of the value of the Nation's 35 percent of irrigated lands in crops. the West have a salinity problem. 412 Managing Natural Resource Systems
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Maintenance of are all meas- Role of Chemicals wetlands, care- ures farmers Most farmers rely on chemi- ful application can—and do— cals to raise crop yields: fertil- of chemicals, take to provide and mainte- the quality of izers, herbicides, and insecti- nance of border habitat neces- cides. While these chemicals strips at the sary for have many beneficial effects, edges of fields wildlife. some—if they find their way into water bodies or the food chain— have been implicated as posing Salinity can result in signifi- threats to human or animal cant loss in yields and profits, health. and farmers are seeking ways to Chemicals are very expensive reduce the problem. One way, inputs, and farmers do not like drip-irrigation, reduces the to see off-farm chemical losses amount of water needed to irri- any more than the general pub- gate effectively. Another involves lic. The problem exists in part recirculating water. The least because stopping the movement salty water is used first on the of chemicals to inappropriate crops most adversely affected by places is also expensive. salt As the water gets saltier, Techniques exist for curtailing subsequent uses are on less use of chemicals without cutting sensitive crops. How Farmers Affect Natural Resources 413
Energy has been used not only to improve jields, but to curb crop spoilage risks after har- vest—by drying or refrigeration. Still, energy is a small propor- tion of total production costs; 3 percent of total energy use in 1974 was for food production. So farmers do not make dramatic adjustments to rising real costs of energy. Changes are occur- ring, however, to reduce the use of energy for irrigation via water conservation measures such as irrigation scheduling, or reduc- ing chemical use with more fer- tilizer-sensitive plants, recycling animal wastes, or integrated pest management Besides producing food and fi- ber, cropland, pastureland and rangeland are—if managed cor- rectly—excellent habitat for many wildlife species. Border yields. One—integrated pest strips at the edge of fields, care- management—in some cases fully applying chemicals, and substitutes biological and other maintaining wetlands can pro- methods for chemical control. In vide the quality of habitat other instances it involves using needed. chemicals as effectively as possi- In contrast, converting wet- ble so not as much is required. lands to cropland, planting fence Organic farming methods may row to fence row, and removing cut chemical needs without re- windbreeiks all may have harmful ducing net farm income. effects on wildlife. What's more, irrigation expansion can bring Energy, Wildlife river systems below the water Historically, the farm sector level needed to support fish and has responded to relatively low other water-dependent species. energy prices by substituting While in some cases protect- chemicals and fuel for labor and ing wildlife habitat will mean land. Fuel, for example, can be tradeoffs in agricultural produc- used to irrigate crops and offset tion, often relatively minor vulnerability of the harvest to changes in farm operations can bad weather. Energy—through avoid detrimental wildlife im- chemicals—can protect crops pacts or increase positive from pests. effects.