Standard methods of applying pest-control chemicals and other compounds to plants, animals, soils, or agricultural products. For spraying, chemicals are dissolved or suspended in water or, less commonly, in an oil-based carrier. The mixture is then applied as a fine mist. In dusting, dry, finely powdered chemicals may be mixed with an inert carrier and applied with a blower. In fumigation, gases or the vapours of volatile compounds are held in contact with the materials to be treated. Sprays and dusts are used to control insects, mites, fungi, and bacterial diseases of plants; disease-spreading insects, such as lice and flies, on animals; and weeds. They are also used to apply mineral fertilizers, to increase or decrease fruit set, to delay the dropping of nearly mature fruits, and to defoliate plants to facilitate harvesting (e.g., of cotton; see defoliant). Sprays adhere to treated surfaces better than dusts do. Fumigation may be used to control insects and some diseases in stored products or to control insects and sometimes fungi and weeds in soil. Increasing use of spraying and dusting has prompted concern over their impact on the environment, the food chain, the water supply, and public health. New chemicals and precautions have only partially allayed these concerns. Seealso crop duster; fungicide; herbicide; insecticide.
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Cormack is a farming community on the Great Northern Peninsula of Newfoundland.
The government of Newfoundland also runs a 243 hectares (600 acre) community pasture, the largest of thirty throughout Newfoundland, providing cheap grazing for the cattle and sheep of the Cormack farmers and allowing the farmers' own land to be sown for winter feed. The government also provides veterinary services, mineral supplements, a programme of spraying and dusting for parasites, and the services of a purebred bull at the community pasture.
The first attempts at farming in Cormack were abandoned mainly because of limited access to markets and competition from mainland farmers. Both still presented problems in the late 1970s. A report in The Rounder (Nov. 1977) stated that high costs of feed, fertilizer, machinery and transportation, and a small market base contributed to keeping many farmers from growing large enough crops to compete outside the Province. Small farmers who do not sell to wholesalers have to truck their produce about locally and that has increased transportation costs. Another problem has been the dumping, mainly of potatoes, by mainland producers, thus flooding the market and causing prices to drop. In 1977 the Vegetable Marketing Associates Limited (VMAL) was formed to help combat these problems and to coördinate marketing efforts. Several of the larger vegetable producers from Cormack joined and in 1979 the Department of Rural, Agricultural and Northern Development built and equipped a centralized processing building at Cormack.