What is a tank-mix incompatibility and how can you check for it?

• A. It occurs when two products mix well, potentially causing homogeneous solution; jar test is not needed.
• B. It occurs when two products do not mix well, potentially causing precipitation or reduced efficacy; test with a jar test before mixing.
• C. It occurs when products are expensive.
• D. It occurs when mixing increases pest resistance.

Answer: (B)

Tank-mix incompatibility means two products won’t stay evenly mixed in the spray tank, which can lead to issues like clouding, separation, or precipitation and can reduce how well the products work together. To check for it, perform a jar test using the same amounts and water you plan to use. In a clear jar, mix the products with water (and any recommended adjuvants) the way you would in the tank, then shake thoroughly and observe right away and after a set period (such as 15 minutes to 24 hours). If the mixture stays uniform with no visible separation or sediment, it’s generally compatible. If you see cloudiness, layering, or precipitate, it indicates incompatibility and you should not tank-mix those products without adjustments. This is why the test before mixing is essential.