Go anywhere where the ground is normally damp in Dorset and you are likely to find hemp-agrimony (Eupatorium cannabinum). It will be found along river banks, lake sides, in fens, marshes, wet meadows, damp woodlands; it just needs damp ground.
No relation to agrimony despite the similar name (both English and scientific), hemp-agrimony is a member of the daisy family and has lovely soft padded flower heads which insects adore. It is always worth browsing the flowers of hemp-agrimony to see who is at home! Once the flowers go over then the finches move in to feed on the seed heads. All things considered hemp-agrimony is a top flower! Good to see, good for insects and good for seed eating birds.
Also known as holy rope, goodness knows why but I guess rope used to be made out of hemp, the plant contains chemicals known to cause cancers so best not to collect it and smoke it although despite the name cannabinum I have not found a link to cannabis!