Am willing to be shouted down.
My 9 month old pup is lovely but won't shut up in the garden. He barks at planes, cars - 50 yards away behind a fence on the street, obviously anyone approaching the front door, squirrels, birds, everything.
We say "No!" in a deep voice but then he lies there gruffing and growling thinking about invaders. Sometimes he wakes us up at night and seems so convincing that we let him out the back door and it is just squirrels.
What about one of those American anti-bark collars?