I use Pathclear for the weeds that come up between flags etc. You dilute it per the instructions and spray or sprinkle it on. The weeds turn brown in 3 or 4 days and it gets to the roots too. You only need to keep the children away until it dries, about 10 minutes, that's unless they are in the habit of eating weeds (in which case you wouldn't need to use weedkiller, would you?
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