Alder root

Hello, this is my first post and I hope I have posted it in the correct area. My question is can anyone give me a solution to alder root which is beginning to overrun certain areas of my garden. There are a number of alder trees closeby that I believe belong to United Utilities and each year they obviously disperse their seeds, most of which seem to choose my garden. It then spreads like wildfire. I realise whatever suggestions are given will have to be done each year but if I can eradicate them for a season I would be happy with that. Help!

 

Welcome!

Are you sure it's not Ground Elder? The leaves look the same, but it's an underground-propagating nightmare... If it's this, it took us a lot of roundup last year, and some of the black sheeting the farmer uses for silage to get rid of it for this year. One tiny bit of root left can make it spread like wildfire again :( IF it's this you've got