During the motorcycle race, Hank takes a spill and gets his entire left side caked with wet mud. The rest of the race and picnic, the level of mud on Hank's clothes changes back and forth from muddy to not-so-muddy.
In the fox-hunt scene, when the fox jumps over the fence, it becomes apparent that the fox is wearing a 1/4" black collar with a little tiny bell on it.
When the Stampers are throwing dynamite at the small boat, pyrotechnics can be seen floating in the water where the "dynamite" is thrown.