Which two factors are most important in avoiding vapor drift?

The correct answer emphasizes the significance of temperature and pesticide volatility in preventing vapor drift during pesticide application.

Temperature directly influences the volatility of pesticides; as temperatures rise, certain pesticides can vaporize more readily into the air. This increased vaporization can lead to drift, where the pesticide particles are carried away from the intended application site by air currents. Understanding how temperature affects pesticide behavior is crucial for effective application.

Pesticide volatility refers to the tendency of a pesticide to evaporate into the air. Pesticides with high volatility can easily transition from a liquid to a gas state, increasing the risk of drift, especially in warm conditions. Awareness of a pesticide’s properties, including its volatility, helps operators choose products that minimize drift and select appropriate timing and conditions for application.

Factors like humidity, wind speed, rainfall, and soil moisture may contribute to the overall environmental conditions for pesticide application but are less directly related to the inherent properties of the pesticide itself in terms of drift prevention. While these factors can influence the effectiveness and safety of pesticide use, they do not have the same direct correlation with vapor drift as temperature and volatility do.