Can anyone give me any advice as to how I can get rid of that pernicious weed Equisetum, (Horse or Mare's Tail), please? It is rapidly taking over my garden, happily growing through the weed barrier membrane I laid, and the layer of gravel on top of that. The soil is fairly heavy clay. My neighbour has some growing up between her block paving. She tried a herbicide, I'm not sure which type, but think it may have been a systemic one. I told her to crush the plant first, because of the silica, and she did have some success, albeit temporary, in taking off the top growth. But it obviously didn't reach the roots, as it keeps reappearing. I know it is impossible to dig out, so at the moment I am just removing stems manually, working on the assumption that if I can stop it getting any light it's bound to die eventually. But I can't keep up with it. It's getting worse every year. If some sort of hard landscaping, for example resin bonded gravel, could stop it in the paths, I could perhaps then manage to keep on top of it in the flower beds. But I don't want to waste money paying someone to lay the paths, if it is still going to get through and ruin them. No wonder it's been around for millions of years! It's a survivor. I'm beginning to think that in another million years it'll be the only plant left in what used to be my beloved rose garden. I'd welcome any success stories. Thanks.