I think Deep Root has recently been taken of the market.
Mare's tails are probably the most difficult weed of all. They have roots all the way to Australia and any little bit will grow.
Jane I think the best you can do is spray with Glyphosphate. You will have to do it regularly as it keeps them under control but doesn't get rid of them.
It's hopeless trying to bruise them. You just get bits everywhere.
I think the Glyphosphate does work better if you wet them with soapy water first.
Good luck.

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