MDARD Michigan Core Pesticide Applicator Practice Exam

Which factor does NOT contribute to increased vaporship from pesticides?

1. High air temperature

2. Low relative humidity

3. High moisture content in the soil

4. Decreasing size of droplets

The correct answer is: High moisture content in the soil

Increased vaporship from pesticides is influenced by several environmental factors, including temperature, humidity, and droplet size. High air temperatures can enhance the volatilization process, leading to increased vaporization of pesticides. Low relative humidity can also contribute to higher rates of evaporation, as dry air allows for more moisture to escape into the atmosphere. The size of droplets is another critical factor; smaller droplets have a higher surface area-to-volume ratio, which increases the rate of evaporation and consequently the vaporship. Conversely, high moisture content in the soil does not contribute to increased vaporship; rather, it can have the opposite effect. When soil is saturated with moisture, it can lead to reduced evaporation from the soil surface and a lower likelihood of pesticide vaporization. Moist conditions generally promote pesticide retention in the soil rather than its transition into vapor form. Thus, high moisture content in soil acts as a mitigating factor against vaporship.