What type of herbicide is applied to control weeds after they have emerged from the soil?

The type of herbicide that is applied to control weeds after they have emerged from the soil is known as a postemergence herbicide. These herbicides are designed to target and kill actively growing weeds, which makes them effective for use once the weeds are visible and established above the soil surface. Postemergence herbicides are formulated to penetrate plant tissues and disrupt processes such as photosynthesis or growth, leading to the wilting and eventual death of the target weeds.

In contrast, preemergence herbicides are applied before the weeds germinate and are intended to prevent weed seeds from sprouting. Selective herbicides are those that specifically target certain types of plants—such as broadleaf weeds while sparing grasses—while residual herbicides act over a longer period to inhibit weed growth but may not directly kill established weeds. Understanding these distinctions is crucial for effective weed management in turf and ornamental applications.