J
If when you start digging the plot you take spits out that are about six inch thick, spade depth, turn them, break them and pick out every bit out root that you see you will have broken the back of the marestail, this is what I did on my plot I then kept a spray full of deep root ( I got a couple of packets from homebase about three weeks ago) and every time a shoot appears I gave it a squirt, I went from a plot covered in marestail to a plot with an odd bit here and there, lot of work but worth it.