Iowa Pesticide Applicator Practice Exam

What kind of incompatibility occurs when products do not stay uniformly mixed in the spray tank?

1. Chemical incompatibility

2. Physical incompatibility

3. Biological incompatibility

4. Environmental incompatibility

The correct answer is: Physical incompatibility

The concept of physical incompatibility is central to understanding issues that arise during the mixing of pesticide products in a spray tank. This type of incompatibility occurs when two or more products do not mix uniformly, leading to separation or the formation of layers. In practice, this can manifest as undissolved particles, precipitates, or floating residues that can settle at the bottom of the tank. When products exhibit physical incompatibility, it often results in inefficient application because the intended mixture may not deliver the desired effectiveness. For instance, if a pesticide is not properly mixed with an adjuvant or another pesticide formulation, the resulting application may not provide adequate control of the target pest, or it might cause harm to non-target organisms. Understanding physical incompatibility is crucial for applicators to ensure they achieve optimal performance from their pesticide applications. Proper mixing techniques, as well as knowledge of the physical properties of the products being used, can help prevent these types of incompatibility.