True or False: The best time to control perennial broadleaf weeds in turf is the fall.

• A. Depends on species
• B. True
• C. Spring
• D. False

Answer: (B)

Fall is the best time to control perennial broadleaf weeds in turf because these weeds store energy in their root systems as they prepare for winter. Many broadleaf herbicides are systemic, moving from the foliage down into the plant’s roots and crowns. In autumn, perennials actively translocate carbohydrates to their roots, which helps pull the herbicide to the very parts where these weeds survive year to year. At the same time, cool-season turf grasses are still growing that season, so the foliage takes up the herbicide well, and the moderate fall temperatures reduce plant stress and minimize turf injury or chemical loss. This combination leads to more effective control of perennials with typically fewer applications, so fall is regarded as the optimal window.