Preemergence herbicides are generally viable for controlling broadleaf weeds in established turf.

• A. Sometimes
• B. False
• C. Not sure
• D. True

Answer: (B)

Preemergence herbicides work by creating a barrier in the soil that prevents weed seeds from germinating. They’re most effective against annual weeds that sprout from seed after you apply them, not against weeds that are already present or emerging later. In established turf, broadleaf weeds are typically existing plants or they germinate at different times, so a preemergence product won’t reliably kill them. For broadleaf control in an established lawn, postemergence products that target actively growing weeds are the usual approach. Some preemergence products may offer limited activity on certain weeds, but they’re not considered a dependable solution for broadleaf control in established turf.