Burweed or sticker weed(Soliva pterosperma), is a cool season weed that germinates in the early fall as temperatures cool and it grows over the winter. It flowers and produces seed pods in the spring period. It is the seed pods that cause problems as they are spiny. The spines on the pods can painfully puncture feet when walked on barefooted. Once the spiny seed pods have formed, there is nothing you can do to alleviate the problem.
A two prong approach will work best with burweed or sticker weed. The first effort is preemptive and involves the use of a preemergence herbicide or weed preventer. A preemergence herbicide is applied before the seeds start germinating in the fall, and it kills the seeds as they germinate. Early application before seeds germinate is critical. Apply the preemergence herbicide in early October following label directions. Looks for products such as Sta-Green Crab-Ex, Green Light Crabgrass Preventer 2, Hi-Yield Turf and Ornamental Weed and Grass Stopper, Scotts Halts and other brands at your local nursery (ask the staff to help you select the proper product) That’s the first line of attack.
Then, look over your lawn very carefully in December, January and February. If you see any young plants that managed to get by the preemergence herbicide application, spray the lawn with a lawn weed killer like Weed B Gon, Weed Free Zone, Atrazine or other brands of lawn weed killers at your local nursery. If needed, you could make second application following label directions. That’s your second line of attack.
The LSU AgCenter and the LSU College of Agriculture