What type of herbicide application occurs before weeds or desired plants emerge?

A preemergence application refers to the use of herbicides applied to the soil before the emergence of weeds or desired plants. This application method is specifically designed to target germinating weed seeds by preventing their growth and development as they start to sprout. The herbicide typically works by forming a barrier in the soil, inhibiting seedling establishment.

This approach is advantageous because it can significantly reduce weed populations before they can compete with desired plants, leading to more effective weed management and healthier crops. By preventing weeds from emerging in the first place, preemergence application can save time and resources that would otherwise be spent on postemergence treatments later in the growing season.

In contrast, postemergence application involves treating established weeds after they have emerged, which is effective but often requires a different strategy and timing. A foliar application specifically targets the leaf surfaces of plants, while a basal application usually refers to applying herbicides to the base of woody plants. Understanding the timing and application methods for herbicides is crucial for effective weed control.