Answer: I think you might be referring to the soil tiller brand Rototiller. Sometimes an area is tilled to remove existing vegetation. This can backfire if there are live perennial weeds such as dandelions that can resprout from little bits of root left in the ground. Killing out an entire lawn is pretty drastic. Sometimes you can salvage a lawn by giving it good care for a year or two. I think you might find the following information helpful.
Good luck with your lawn!
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