Q: I have an obnoxious, unkillable, unpreventable WEED in my lawn. It is low growing and the leaves look a little bit like parsley. In summer it has almost-invisible stickers that make going barefoot impossible. I never had this weed until three years ago.
A: You have lawn burweed. It’s an annual plant so preventing seed germination each year is absolutely vital.
Spread a pre-emergent that contains isoxaben or trifluralin (click for sources) in early September to prevent the seed from germinating. Check the label to be sure the product prevents broadleafed weeds and that it can be used on your specific lawn grass.
If you can see the green plants, spray them with a 3-way or 4-way broadleaf weed control product (click for sources).
Be sure your lawn maintenance practices are top-notch. Thickly growing grass shades seeds, preventing germination, and will crowd out new seedlings.
Burweed will die when temperatures approach 90 degrees, usually in late May or early June. When the plant has turned brown, there’s nothing you can do except wear shoes outdoors.
Be sure to read the pesticide label for full directions.