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 Grasslands, Shrublands, DesertsDrylands of the World: NORTH AMERICA: Page 11 Contamination of water and soil in the United States Midwest is a growing problem. A major reason for the continued high use of pesticides is the planting of hybrid seeds bred to produce high yields. First introduced in the 1960s and 1970s, these seeds were touted as bringing about a "Green Revolution" which would feed the world. Massive applications of petroleum-based nitrogen fertilizers, toxic herbicides, insecticides and fungicides are required to grow these weakened, seed-heavy plants (Ehrenfeld 1997). The costs of these chemicals and the giant machines needed to sow, apply pesticides and reap crops are so prohibitive that farmers become indebted, often losing their farms when crops fail (Ehrenfeld 1997). Green Revolution programs started and failed in many Third World countries, yet are still widespread. India, southeastern Asian countries and many Latin American nations experienced high yields at first, which later dropped, and incurred heavy debts from both the cost of the seed and the chemicals needed to grow these crops.
A more recent approach to insect and weed pests is the creation of genetically engineered versions of crop plants to resist certain diseases and pests. Genes from one plant resistant to disease are implanted in another, with only the disease-resistance trait passing on in theory. In practice, genes have many traits with the potential of being introduced, creating a plant with uncontrollable characteristics that might become established in the wild, overwhelming native plants (Ehrenfeld 1997). Genetically engineered versions of many food plants are grown on millions of acres in the United States. Some of these genetically engineered seeds have been implanted with the genes of animals, including fish, to impart various qualities such as resistance to cold (Feder 2000). The dangers of such manipulations are great, and many biologists have expressed serious reservations about these new man-made creations. The Last Harvest. The Genetic Gamble That Threatens to Destroy American Agriculture (Raeburn 1995) examines the potential threats.
One dangerous trend in genetic engineering of crop plants is the development of soybeans and other crop plants that are immune to the effects of herbicides, encouraging farmers to broadcast large amounts of these toxic chemicals, which are associated with human illness, including lymphoma (Ehrenfeld 1997). A leader in bio-engineering of crop plants is Monsanto, which also manufactures the herbicide Roundup, a product that has experienced unprecedented high sales in recent years due to the growth in sales of genetically engineered seeds. Rutgers University biology professor, David Ehrenfeld (1997), considers the genetic engineering trend to be a "Techno-pox upon the Land," whose approach ignores the "great complexity of living organisms and the consequences of tampering with them." Monsanto has funded a center at the famed Missouri Botanical Garden for research, which has angered many who are opposed to both genetic engineering and the toxic agricultural chemicals (Jackson 1998). For many Americans and the majority of Western Europeans, food produced in this manner is "Frankenfood" or Frankenstein-like creations that might harm people as well as the environment. Although European countries and many U.S. food processors reject genetically engineered grains, their use, as well as other crops with genes implanted from a wide variety of organisms from nuts to trout, is widespread in hundreds of products. Other countries, such as China, are eagerly introducing bioengineered crops.
Genetically engineered crops also present dangers to wild plants and animals, many of which are endangered, living in remnant prairies, roadsides and pastures. These areas provide vital habitat and feeding grounds for grassland birds, butterflies and other wildlife. Many bioengineered crops containing pesticide genes threaten these prairie vestiges. Monarch Butterflies are the most familiar butterflies in North America, ranging throughout the continent, their black-and-orange wings brightening gardens and fields as they migrate in spring and fall. Scientists recently found, however, that genetically engineered corn implanted with Bt, thought to be a fairly benign and natural pesticide, could spread pollen that was toxic to these beautiful butterflies and other beneficial insects (Feder 2000). Although conservationists and organic food advocates have campaigned against the use of this corn, the highly profitable bioengineering industry fought back with studies that concluded that the corn was not a threat to the butterflies. The United States government has no laws governing the effects on the environment of such crops, or even extensive field testing, prior to their use.
Far more ecologically benign is organic farming. Using natural fertilizers such as manure and plant material, rotating crops to enrich the soil and enhancing habitat for natural pest controllers, including birds and predatory insects, are all age-old farming methods. Those farmers who have used these methods have kept land fertile and yields high indefinitely. Within the past few decades, the pendulum has begun to swing away from synthetic pesticides, herbicides and fertilizers back to the natural approach to farming in the United States and elsewhere in the world. More and more American farms are returning to this method. Sales of organic food are rising in the United States at a phenomenal rate, fed by a market willing to pay more for chemical-free food. This farming does not contaminate ground water, eliminate native plants and invertebrates with herbicides and fungicides, or kill wildlife with pesticides.
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