Which formulation is ready-to-use and requires no further dilution before application, useful for structural and institutional pests, but is high-cost per unit AI and cannot be used as plant sprays?

• A. Emulsifiable Concentrates (EC or E)
• B. Ready-to-use Low-concentrate Solutions (RTU)
• C. Ultra-low Volume (ULV)
• D. Insecticide Dusts

Answer: (B)

Ready-to-use formulations are pre-mixed products that you apply directly without any dilution. They’re designed for quick, targeted use in structures and institutions—think treating cracks, crevices, baseboards, and other indoor surfaces for pests like ants, cockroaches, and stored-product insects. Because you’re paying for a ready mix and the convenience of not diluting, the cost per unit of active ingredient is higher. These products are typically labeled only for structural or indoor use and are not formulated or approved for spraying on living plants, which is why they can’t be used as plant sprays.