Posted: 18/08/2016 at 10:50
Ordinary hogweed is not harmful - as children we picked arms full of it to feed the pet rabbits.
Giant Hogweed is the nasty one, and it is Giant, and hardly missable
This will help you to identify it http://www.wildfooduk.com/articles/giant-hogweed-and-common-hogweed/
Spurge is the other plant which can cause problems, if the sap gets onto your skin.