Among the following formulations (L, EC, WP, S), which should be added last when mixing in a spray tank?

• A. L
• B. WP
• C. EC
• D. S

Answer: (C)

When mixing pesticides in a spray tank, the order you add products matters for compatibility, dissolution, and uniformity. Emulsifiable concentrates are solvent-based liquids with emulsifiers that can interact with other ingredients if added too early. Adding them last allows the dry and solid formulations (and any soluble components) to be wetted and dispersed first, so the EC can blend in smoothly without causing clumping, premature emulsions, or separation. With the EC introduced at the end, the overall mixture forms a stable, uniform spray rather than having solids trapped or unevenly dispersed by an early solvent effect. Always follow the label, but this rationale explains why the emulsifiable concentrate is placed last.