Hi, welcome to GoY, I think you mean horsetails, Hippuris vulgaris is an aquatic plant, common name marestail, Equisetum arvense, is a herbaceous perennial, common name horsetails, the 2 species are unrelated.
This used to be used to scour pots and pans many years ago, I think it's main aim in life now is to keep gardeners busy, trying to eliminate it.
I mentioned it in a blog I did in december 2012, called Gods gift to us, can't remember if it's in part 1 or part 2, Derek.

Never heard of any biodiversity value though I have a vague memory of them being a herbal remedy for something. If you are going to try weedkiller bruise them throughly first so they stand a chance of absorbing it. When they come back in the spring make sure you remove especially the ones with little black knobs at the top as theyse are the fruiting heads where the spores are.

Thanks both for your helpful advice. Derek, I will check out your post as you suggest.