Most definitely edible! Feasted on by insects, birds and mammals, including humans. And very tasty they are too! According to folklore, St Michael cast the devil out of heaven and he landed in a bramble bush and cursed it. As a result of this curse it is said that blackberries become unpalatable around St Michael's Day (29 September) after which they should not be picked. Be that as it may, I tasted one today and it was very tasty despite that curse
