By Dr. Jack Fry
Crabgrass emergence was evident last weekend – at least in Olathe, KS (picture below).
Crabgrass seedlings (inside white border) emerging on April 19, 2020 in Olathe, KS.
This was on bare soil next to a paved sidewalk. It can take a few weeks longer for crabgrass to emerge within areas of thin turf due to cooler soil temperatures (see article on timing herbicide applications here: Flowering Ornamentals and Crabgrass Emergence). So, on a lawn of acceptable quality (and no bare areas), you should still have time to get a preemergence herbicide out. Once you see crabgrass such as this emerging within a lawn, consider using a preemergence herbicide that has postemergence activity, such as dithiopyr (Dimension) or mesotrione (Tenacity). Of course, there are also a number of postemergence herbicides that can be used for crabgrass control as well.
Always remember to READ THE LABEL for the correct rate, turfgrass tolerance, and specific instructions before application!!!
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