I'd agree with you Lilbun.
We used to eat all sorts of things from the hedgerows years ago. But there were very few cars then, so pollution was less of an issue.
The sea was cleaner too.
We'd put very young hawthorn leaves in cheese sandwiches like lettuce too. Some how I don't think your Mum would want to "cook wild" abi2047.
With stingers, there's a knack to picking them. Don't try to learn until spring, on the baby stingers. There's lots of little hairs under the leaves. If you touch them lightly they'll sting you. If you grip hard you crush the hairs before they can sting you. It needs a lot of practice! Also I've never found dock much use for nettle stings, but
greater plantain leaves rubbed on, seem much better.