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The main purpose of this smdy was to determine and analyze farmers' perceptions regarding the adoption of selected sustainable agriculture practices specifically associated with weed control in Iowa. A secondary purpose was to identify the implications to agricultural extension education. The study revealed ±at farmers use a combination of various weed control methods including chemical control, cultivation, soil fertility management, crop rotation, and crop diversification. Farmers in this smdy indicated that they were supportive of educational program focused on sustainable agricultural practices. The challenge that faces extension educators is to design educational programs that fit the needs of farmers. Fanners lacked a clear understanding of what agricultural practices are thought to contribute to sustainability of natural resources. The extent to which fanners used soil fertility management and crop rotation indicated that these practices could be useful in controlling weeds. Demographic characteristics of the farmers in the smdy revealed that adoption of sustainable agriculture practices associated with weed control depends on the age of the farmer, the numbers of years in farming, the number of acres owned, the number of acres rented, the level of education and the level of income earned from fanning. Farmers in the study participated in government programs, however, they did not consider government policy incentives as a part of ±e strategy for implementing sustainable agricultural practices. The study confirmed that farmers considered conservation tillage, long-term consideration for food safety, appropriate pricing of farm products, and the X practice of weed scouting as important strategies for implementing sustainable agricultural practices. Farmers indicated that the best sources of agricultural information include on-fann demonstrations, field days and magazines. 1 CHAPTER I. INTRODUCTION The definition of sustainable agriculture given in the Food, Agriculture, Conservation, and Trade Act of 1990 is stated as: Sustainable agriculture is an integrated system of plant and animal production practices having a site specific application that will, over the long-term satisfy human food and fiber needs, enhance environmental quality and natural resource base upon which the agriculture economy depends, make the most efficient use of non-renewable resources, and on-farm/ranch resources and integrate, where appropriate, natural biological cycles and controls, sustain the economic viability of farm/ranch operations, and enhance the quality of life for farmers/ranchers and society as a whole. (US. Congress, 1990, p. 3) Several investigators have defined sustainable agriculture (Allen et al., 1991; Caldwell, 1994; Crosson, 1992). While each definition of sustainable agriculture is site specific and differs from region to region, investigators have yet to agree as to what actually they mean by sustainable agriculture. Lockeretz (1988) stated that the phrase "lowmput/sustainable agriculture" often is used synonym...

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