I bet they were picking it to eat. The stalks taste a bit like a cross between aniseed and liquorice, a kind of flavour often used in African cooking.

You have to be 110% sure what your picking cow parsley and not hemlock, which looks very similar and is deadly. I hope they know what they're doing! (Hemlock flowers slightly later, is a bit taller and has tiny purple spots on the stalks)

I even have a recipe for pickled cow parsley stems somewhere...

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