Insecticides for pest control are applied to soil and crops in the form of granules, dust, or liquid sprays. A variety of mechanical spraying and dusting equipment is used to spread chemicals on crops and fields; the machinery may be self-powered, or drawn and powered by a tractor. In areas where large crops of vegetables and grain are grown, aircraft are sometimes used to dust or spray pesticides.
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The machinery may be self-powered, or drawn and powered by …
a car
a truck
a lorry
a tractor