No, it won't work on its own - you need a systematic approach, I'm afraid, involving, inevitably, elbow grease. Spray the glyphosphate onto the ground elder when its growing strongly, the soil is moist, but no rain is expected for a few hours. Wait a fortnight and respray (under the same conditions, doesn't matter if its only 12 days or ten days or 16 days, but no longer or less). Wait a week or ten days, now dig it out, removing it all by the roots. All the glyphosphate does in my experience is kill off the tiny, hair like roots, leaving just the main white roots, which you can then dig out with a fair amount of success. You may need to repeat the whole process on any bits left later on.

Welcome, Alan! I'm sorry but I don't quite understand what you are asking, though I, too, have had my issues with RoundUp!

Whoa! Bamboo, you must have been posting while I was typing. I'm glad you knew what Alan was referring to! I hadn't got that far down the list yet.

He asked a question earlier about ground elder, and someone suggested glyphosphate, and then he posted this one separately, Tugbrethil! And did you get my PM?

well I have never had any problems with roundup. but you have to give it time to work. systemics take upto a month to get into the cells of the plant and do its job.

If you want a 'quick fix' then you are out of luck you will have to dig it out, making sure you get every 'pip' small growing point out of the soil. as bamboo says good old fashioned elbow grease.

I've had trouble with it, Seaburngirl, which is why I developed the method described above to get rid of ground elder - I found the round up just wasn't up to the job in terms of permanently killing it off.

I 've never used it on g.e. but i have used it on bindweed and creeping sow thistle. I tend to spray it late summer so it translocates it to the underground storage bits. then it doesnt come back.
I removed g.e by digging and sifting all the soil in a 30ftx5ft border. took several weeks but it certainly got rid of it apart from 3/5 pieces that i had missed. as you said elbow grease. no quick fix. :o)

glyphosphate were do you buy it from

is there any think eles apart from round up

Glycophosphate is an ingredient in many weedkillers. Roundup contains it. look at the ingredients on weedkillers like weedol and see if it contains it. The good thing about it is when it lands on the soil it becomes inactive/inert.

I think places like Wilkinson do their own version of glyphosphate, which is cheaper.