If crabgrass was a problem last season, what sequence should you follow to manage it this year?

If crabgrass was a problem last season, what sequence should you follow to manage it this year?

• A. Wait until crabgrass is large then treat.
• B. Monitor crabgrass and apply a postemergence herbicide if patches appear.
• C. Apply only to bare soil.
• D. Promote turfgrass growth and start with a preemergence in early spring; reseed patches if they appear.

Answer: (D)

The main idea is to prevent crabgrass before it starts and strengthen the turf so it competes better. If crabgrass was a problem last season, the best sequence is to promote healthy turf growth and start with a preemergence herbicide in early spring, then reseed any patches that appear. A preemergent acts as a barrier in the soil to stop crabgrass seeds from germinating as temperatures rise, so you’re stopping the weed before it takes hold rather than chasing it after it’s already present. Strengthening the turf reduces bare soil and creates competition that discourages future crabgrass establishment. If bare spots do appear, reseeding them helps rebuild a dense stand that’s more resistant to future outbreaks. Why the other approaches aren’t as effective: waiting until crabgrass is large lets the weed establish and compete with the turf, making control harder and less reliable. Relying on postemergence treatments after patches appear is reactive and often less effective for wide areas, potentially requiring multiple applications and risking turf injury. Applying herbicide only to bare soil ignores the rest of the turf that can still harbor seeds and allows crabgrass to germinate elsewhere, whereas a proactive, whole-turf approach with early-season preemergence and reseeding patches addresses the problem at its source.

The main idea is to prevent crabgrass before it starts and strengthen the turf so it competes better. If crabgrass was a problem last season, the best sequence is to promote healthy turf growth and start with a preemergence herbicide in early spring, then reseed any patches that appear. A preemergent acts as a barrier in the soil to stop crabgrass seeds from germinating as temperatures rise, so you’re stopping the weed before it takes hold rather than chasing it after it’s already present. Strengthening the turf reduces bare soil and creates competition that discourages future crabgrass establishment. If bare spots do appear, reseeding them helps rebuild a dense stand that’s more resistant to future outbreaks.

Why the other approaches aren’t as effective: waiting until crabgrass is large lets the weed establish and compete with the turf, making control harder and less reliable. Relying on postemergence treatments after patches appear is reactive and often less effective for wide areas, potentially requiring multiple applications and risking turf injury. Applying herbicide only to bare soil ignores the rest of the turf that can still harbor seeds and allows crabgrass to germinate elsewhere, whereas a proactive, whole-turf approach with early-season preemergence and reseeding patches addresses the problem at its source.