North Carolina Pesticide Application Practice Test

Which form of pesticide requires constant agitation when mixed with water?

1. Wettable Powder

2. Water Dispersible Granule

3. Emulsifiable Concentrate

4. Adjuvant

The correct answer is: Wettable Powder

Wettable powders require constant agitation when mixed with water due to their physical properties. These formulations consist of solid particles that do not dissolve in water but rather suspend within it. When wettable powders are added to water, they tend to settle at the bottom of the container if not mixed continuously. Agitation helps maintain a uniform suspension of the particles, ensuring that the pesticide is evenly distributed throughout the mixture. Proper agitation is crucial for effective application, as it ensures that the targeted crops or pests receive the correct dosage of the active ingredient. In contrast, water dispersible granules dissolve more readily in water and form stable suspensions without constant agitation, making them easier to work with. Emulsifiable concentrates form a stable emulsion when mixed with water, which reduces the need for continuous stirring. Adjuvants, while they can be used to enhance pesticide effectiveness, do not primarily serve the same purpose as the main active ingredients in pesticide formulations and typically do not require continuous agitation in the same way that wettable powders do.