Removing Weeds from a large garden plot

Hi there,
My friend has this weed growth, (it looks like Comfrey) for many years in her garden. Do we need to dig it out (big job) or is there a way we can assist this process ourselves either chemical or organic - I'd like to work on the plot laying lawn etc this Spring. Can anyone accurately tell me what they see here and what we might do to take steps to create lawn later on.. Many Thanks!

 

Thank you guys -apparently the roots are 3 foot deep and they've been set in there for years and years - will we need a glysophate concentrate? Bottles of roundup could be expensive. The plot is 10mx12m

 

Personally I use Gallup 360. I have a big garden of nearly 2 acres and a field of 5 acres to look after so need to finding savings where I can but also have to buy most things in bulk. I have found Gallup pretty much the same as Roundup but not so expensive. I try to use very
little weed killer but there are occasions and situations where there isn't much alternative.Definitely don't go for any types of ready mixed weed killers, you'd be spending lots of money on water! There are cheaper alternatives to Gallup but you need to keep an eye on the concerntrations. Often cheap means weak. Others may have alternative suggestions which may be better but I'm quite satisfied with using Gallup.