They are horse-tail, Equisetum Arvense. I'm afraid almost impossible to destroy, but may be controlled. On lawns, just mow as usual, on paving slabs, crush them and pull out. Or use one of those L-shaped patio weeders.
Nasty stuff and as borderline says impossible to eradicate completely. If you can go out daily and weed them out it will help certainly don't let them grow. I used to make up a strong mix of glysophate weedkiller with a drop of washing up liquid and crush the plant and paint it with the solution as mine were through tarmac as well. They got less over time but we have moved now so no idea whether the new owners kept up with it although I did leave instructions.
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If you can go out daily and weed them out it will help certainly don't let them grow.
I used to make up a strong mix of glysophate weedkiller with a drop of washing up liquid and crush the plant and paint it with the solution as mine were through tarmac as well.
They got less over time but we have moved now so no idea whether the new owners kept up with it although I did leave instructions.