Want to control this weed? I call this the weed from 'heck'. Established plants are nearly impossible to pull......they break off no matter how I use the weeding tool. The plant forms a mat over the existing lawn. I was not able to kill it with Roundup; the bag of corn gluten didn't affect it. I finally discovered Celsius, a herbicide that will kill it without harming the St. Augustine. Expensive, but I mix it 1/4 tsp per 2 cups water so it will last a lifetime or two. I now walk the lawn once or twice a week with the squirt bottle in hand looking for new starts or runners. No, I'm not associated with the product......just wanted to share in case you are as frustrated to control this weed as I was.