of alternative pest-management tools will be critical to meet the production standards and stiff competition expected in these niche markets.

Globalization policies and practices are affecting pest management on and off the farm. Reduction in trade barriers increases competitive pressures and provides extra incentives for United States farmers to reduce costs and increase crop yields. In a global marketplace, United States farmers can compete with farmers from other countries where labor, land, and input costs are lower only by being more “productive,” with higher yields per acre. Other forms of trade barriers create disincentives for adopting new technologies (such as the reluctance of the European Union to accept genetically modified organisms). It is not well understood how globalization will affect agriculture in developing countries, where 80% of the world's population lives (Schuh 1999). It is likely that trade will increase the spread of invasive pest species and pose risks to domestic plants and animals, as well as populations of native flora and fauna. Increased pressure to phase out the widely used ozone-depleting chemical methyl bromide has raised questions as to the availability of cost-effective substitutes. To meet those emerging global pest problems, researchers will need to develop effective, environmentally compatible, and efficient pest controls as a complement to a suite of prevention strategies.

Nontarget effects of exposure of humans and the environment to pesticide residues are a continuing concern. The side effects of pesticide use vary over time and space. In many cases, the environmental damage associated with the application of a chemical in a riparian zone, for example, is much larger than that associated with an application in other areas. When it comes to a local environmental-quality problem caused by pesticide use, application technologies and the location matter much more than the volume of pesticide applied. Numerous studies have shown that pesticides decrease crop loss, but the potential indirect environmental impacts of pesticides are not easily determined. The application of pesticides results in indirect effects on ecosystems by reducing local biodiversity and by changing the flow of energy and nutrients through the system as the biomass attributable to individual species is altered (Chapter 4). Pesticide policies should be based on sound science; where there is uncertainty, expert judgment will become more important in decision-making. Across-the-board pesticide policies that do not account for biological and ecological factors and for socioeconomic influences are likely to be less effective.

Pesticide resistance now is universal across taxa (Chapter 2). Pests will adapt to counter any control strategy that results in the death or reduced fitness of a substantial portion of their population. Cultural and biological controls are not immune to evolution of resistance. Pesticide resistance is conspicuous because of the intensity of selection by high-

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