Which practice is listed as a best management practice to prevent contamination of surface water and groundwater by pesticides?

• A. Using pesticides that are highly water soluble
• B. Using pesticides with high soil-binding properties
• C. Applying pesticides only during rainfall
• D. Calibrating equipment daily

Answer: (A)

Pesticide movement in the environment is strongly influenced by how soluble the product is and how well it sticks to soil. Pesticides that bind tightly to soil particles stay in place, are less likely to be washed into surface water, and less likely to move down to groundwater. That binding property reduces the chance of contamination, making it the best practice for protecting water quality.

In contrast, pesticides that are highly water soluble dissolve easily in water and can be carried away by runoff or percolating water, increasing the risk of surface water and groundwater contamination. Applying only during rainfall would promote runoff and leaching rather than prevent it. Calibrating equipment daily is important for applying the right amount, but it doesn’t address the pesticide’s potential to move with water in the environment.