Who is liable for negative effects resulting from an unspecified tank mix application?

The applicator is primarily liable for any negative effects resulting from an unspecified tank mix application. This liability stems from the fact that the applicator is responsible for the decisions made during the application process, including which pesticides are mixed and used. If an applicator chooses to mix products that were not specifically tested or recommended together, they assume accountability for any adverse outcomes that arise from that choice.

This responsibility is grounded in the knowledge and training that professionals in pest management are expected to have. Applicators must understand the properties of the products they are using, including potential interactions between different pesticides when mixed in a tank. If adverse effects occur, such as harm to non-target organisms, crop injury, or environmental damage, it is the applicator's duty to ensure that applications are made safely and in compliance with label instructions.

The manufacturer of the pesticide, while they provide guidelines, cannot be held responsible for misuse or improper application of their products by the applicator. Similarly, the retailer and the federal government also have roles in regulating and providing information, but ultimate liability for how those products are applied lies with the applicator.