The opening graf from a bit at New York Arts Magazine:

For more than 3,000 years farmers have been using scarecrows to protect their crops from hungry birds. The Greeks carved wooden scarecrows to look like Priapus, the son of the god Dionysus and the goddess Aphrodite. Priapus, who was quite ugly, played in the vineyards, scaring the birds away and protecting the grapes for a good harvest. As farmers picked up on this, they carved wooden statues in the likeness of Priapus, painted the figures purple and put a club in one hand to make the statue more menacing and a sickle in the other for a good harvest.


... personally, I've always wondered about the claims that statues of Priapus were thought to frighten thieves (as mentioned in passing in the Wikipedia article); I think that's one of the only Roman divinities I've ever read of whose statue is 'active' (in the sense of doing something other than 'passively' protecting ... something to be prayed to).