What is the primary purpose of preemergence herbicides in turf?

• A. To kill existing weeds that have already emerged
• B. To enhance turf growth after seeding
• C. To mix with fertilizer to improve uptake
• D. To prevent germination of weed seeds before they emerge

Answer: (D)

Preemergence herbicides work by preventing weed seeds from germinating in turf. They create a chemical barrier in the topsoil that stops seeds from sprouting or early seedling growth, so weeds never establish. Because they must be active before germination, they won’t kill weeds that have already emerged. They aren’t used to boost turf growth, nor are they intended to be mixed with fertilizer to improve uptake. Activation relies on rainfall or irrigation to move the product into the soil, which is why timing and watering after application are important.