Ключевые слова: agriculture, aircraft, airplane, biplane, chemicals, control, crop, cropduster, duster, environment, farm, fertilizer, field, fly, flying, growth, herbicide, horizontal, industry, landscape, low, midair, outdoors, palouse, particle, pesticide, piloting, plane, quality, rural, scene, sprayer, spraying, substance, summer, toxic, washington, weeding, work,