Revealing mistake: When Carl is caddying for the priest during the bad weather, the wind is so strong that it is almost blowing them over but the trees are not moving in the background.
Revealing mistake: During the opening credits, the gopher is tunneling under the grass and plowing it up as he goes. In one of these shots, the path the gopher will take can be seen before he even gets there. The darker special-effects grass that the underground "gopher" will tear up is obvious. (00:00:35)