MDARD Michigan Core Pesticide Applicator Practice Exam

Which formulation should be used when diluting with very hard or alkaline water?

1. Wettable powder

2. Emulsifiable concentrate

3. Flowable formulation

4. Granular formulation

The correct answer is: Emulsifiable concentrate

The emulsifiable concentrate is the best formulation to use when diluting with very hard or alkaline water because it maintains its effectiveness and stability under such conditions. Emulsifiable concentrates contain oil-based ingredients that can disperse in water, providing a stable mixture even when mixed with hard water, which is high in minerals like calcium and magnesium. These minerals can interact negatively with other formulations, potentially causing issues such as reduced efficacy or precipitation. Other formulations may not perform as well with hard or alkaline water. Wettable powders can clump and settle out in hard water due to mineral interference, which can limit coverage and effectiveness. Flowable formulations, while more stable than wettable powders, can still face challenges with solubility in hard water. Granular formulations typically do not require dilution with liquid but will not help if the issue specifically pertains to the water quality for mixing applications. Choosing emulsifiable concentrates in these circumstances helps ensure that the pesticide remains effective in targeting pests, making them a more reliable option in challenging water conditions.