What type of pesticide should be used to manage mosquitoes and black flies by applying to surface water?

• A. A form for terrestrial use
• B. A household pesticide
• C. A formulation that has EPA approval for aquatic sites
• D. A biological control agent

Answer: (C)

When treating surface water for mosquitoes and black flies, you must use a pesticide product that is labeled for aquatic use. Labels approved by the EPA for aquatic sites provide specific instructions on applying to water, including acceptable formulations, rates, timing, and safety precautions to protect fish, aquatic invertebrates, and other wildlife. Using products not labeled for aquatic use can contaminate water, harm non-target organisms, and violate regulations.

Forms meant for terrestrial use are not vetted for water environments, and household pesticides are not approved for aquatic applications, so their use in surface water is inappropriate and often illegal. A biological control agent could be appropriate if it has an aquatic-use label, but without that labeling it falls into the same category of products that aren’t approved for water applications.

So, the best choice is the formulation that has EPA approval for aquatic sites.