While we have no hedges just walls /fences / tree plantations , we have many km of open ditches running within 1mt of the tarmac , all looked after ( or not ) by the council ,same with grass cutting and any scrub overgrowing into the 1mt strip . A friend wanted to replace a fence and thought he had the ground right up to the tarmac , but the council made him take it down and move back to 1 yard from the tarmac