Actress Sarah Edwards, while listed in preview credits and shown in at least one still from "Earthworm Tractors" as Mrs. Blair, was cut from final release prints. She is probably best known for her role as Mrs. Hatch in It's a Wonderful Life.
The name "Earthworm Tractors" is a sly reference to the Caterpillar company, whose name was copyrighted in 1911 and was prominent by the 1930s.