For 4 years, beside my property is another lot being sold but had tons of weeds. My first year, my lawn was nice. My second year, I was battling the weeds at the border. 3rd and 4th year, it's in my lawn. I can't get rid of prickly lettuce. I've apply those Weed b Gone products and they die. But after few weeks, I'll see new seedlings again.

Last Sunday, they were all around 7 inches tall. I just mowed them.

How do I totally successfully eliminate those prickly lettuce on my lawn? I remember when I pulled them, the roots gets cut.