Which of the following control methods is particularly effective for managing established broadleaf weeds?

Herbicide application is particularly effective for managing established broadleaf weeds because it targets the specific physiological processes of these plants. Broadleaf weeds often have different structures and metabolic pathways compared to desirable grasses, making them susceptible to specific herbicides formulated to disrupt their growth. These herbicides can penetrate the broadleaf foliage and move systemically within the plant, effectively stopping growth and allowing for better control compared to other methods.

Methods like frequent mowing can help manage annual weeds and prevent seed set but may not be effective against established broadleaf weeds that can withstand frequent cutting. Soil removal is a more drastic approach that is generally not practical for controlling weeds in established lawns or ornamental landscapes. Increased fertilization can promote the growth of desirable plants but may inadvertently benefit the broadleaf weeds as well, potentially worsening the issue if the conditions favor their growth. Thus, herbicide application is a direct, targeted method to effectively control established broadleaf weeds in a variety of settings.