Burdock is a royal pain in the ar$e! The only way to kill it is to use something 2-4-D, like Weed Be Gone, but you need to catch it early or you have to use a lot of weedkiller to knock it down completely. Otherwise, a spade works if you dig down a bout 8-inches and get the root and crown. You won't get the whole root, it is way too deep.
Burdock had medicinal uses, but the root, NOT the leaves. What you are going to hate the most is the seeds. It is where the idea for Velcro came from. The seed pods are prickly and stick to just about any fabric or hair or wool or fiber of any kind. Got a dog? It will get stuck on you dog. If you get the little dusty sized hooks in your eye, you will want to gouge your eye out, it is hard to remove (the burdock bit, not your eyeball). The only thing I hate growing around here more than burdock is our Elm tree seedlings that pop up everywhere and you can't pull those once they are over a foot tall.
There is also another plant in the same family call curly dock. I can get a picture for you later when I am outside, we have it in some places but it pulls easier than the burdock does.
The other natural way to remove 'dock plants, get some hogs and let them pasture where you have it, they love it and will rut up the roots and all. They also leave fertilizer behind them
