Keeping trees, shrubs, lawns, and crops growing pest-free produces better food crop yields and more beautiful, functional landscapes. Vegetation pesticide handlers mix and apply the chemicals used to prevent or destroy fungi, insects, and predatory plants. Handlers apply chemicals using a variety of methods such as sprays, vapor, or direct mixing into soil. While scientists continue to improve materials and methods for safety and effectiveness, pesticide handlers take precautions in dealing with potential hazardous materials. Pesticide handlers have specialized training to use the correct amount of pesticides to avoid affecting the plants and animals in the treatment area. These workers spend much of their time outdoors, exposed to the weather and contaminants that require they wear safety gear and protective clothing. Work schedules may be long, at times more than 40 hours a week. A high school diploma or equivalent is the typical job requirement, although technical certificates and specialized training may be required to qualify for some positions.