MDARD Michigan Core Pesticide Applicator Practice Exam

What are the two types of incompatibility when mixing pesticides?

1. Physical and chemical compatibility

2. Mechanical and thermal compatibility

3. Physical and thermal compatibility

4. Chemical and biological compatibility

The correct answer is: Physical and chemical compatibility

The correct answer identifies the two types of incompatibility when mixing pesticides as physical and chemical compatibility. Physical incompatibility refers to issues that arise when pesticides do not mix properly, which can lead to problems such as settling, floating, or the formation of clumps and layers. This type of incompatibility can affect how well the pesticides perform, potentially causing uneven application and reduced effectiveness. For example, two products might separate instead of forming a homogenous mixture, leading to improper distribution when applied. Chemical incompatibility, on the other hand, occurs when two or more pesticides react chemically with each other. This reaction can result in the breakdown of the active ingredients, the formation of hazardous byproducts, or a reduction in effectiveness. Understanding chemical compatibility is crucial to preventing phytotoxicity to crops and ensuring that the intended pest control is achieved. These two types of incompatibility are critical for pesticide applicators to consider when preparing mixes, as they directly impact the safety and efficacy of the pesticide applications.