An appalling
stereotype, but a much used one nonetheless, of those that live in the
country, usually as perceived by those who live in the
town.
Typical bumpkins lean over fences whilst wearing
smocks and chewing ears of corn. They have big
noses and one or two missing teeth. There is usually a
haystack somewhere in the background. They are, typically,
unintelligent, and very unhelpful to anyone who doesn't come 'from round these parts'. They always have a
Devon accent, or at least an approximation of it.
Famous 'country bumpkins' are those two off The Two Ronnies, Farmer Palmer from Viz, and Eddie Grundy of The Archers: the tradition is a long established one and harks back to at least the rivalry between town and country from Restoration comedies. Sir Wilfull Witwould is a classic example of a country bumpkin.
As stereotypes go it is an amalgamation of prejudice and misconceptions. There are doubtless county bumpkins out there, but they are certain to be useful and valuable members of society. All that nonesense about always giving tourists misleading directions is hogwash. Of course.