Trivia: At the start of the first technicolor scene where the camera pans across the vegetation to reveal Oz, a pink splodge appears for a single frame, due to a technicolor fault in one of the 3 strips. It is covered up by a single note played on a xylophone to make it appear a deliberate special effect. Faults in the black and white film used to shoot in technicolor always show as vivid color faults in the print.
Trivia: For decades after "The Wizard of Oz" premiered, Margaret Hamilton was often called upon by adoring fans to render her witch's cackle and her most famous movie line: "I'll get you, my pretty, and your little dog, too!" Although she obliged her fans, Hamilton always publicly expressed regret that her Wicked Witch of the West was too frightening for small children. However, after she died in 1985, her only son (Hamilton Wadsworth Meserve) admitted that his mom frequently used her wicked cackle and "I'll get you, my pretty" line in private life as he was growing up, just because she loved doing it.
Trivia: Originally Victor Fleming and Mervyn Leroy (directors) wanted 11-year old Shirley Temple as Dorothy, but she could not perform the key solo 'Over the Rainbow' to their satisfaction in spite multiple rehearsals and takes. So the part was offered to Judy whom Fleming and George Cukor (director) knew could carry the song, in spite that she was too old at 16 to play the part. So she had to be heavily padded to hide her bosom and girlish waistline so that she would look undeveloped, despite that the final results did not completely camouflage her appearance.
Trivia: Billie Burke, who played Glinda the Good Witch, initially auditioned for Aunt Pittypat Hamilton in Gone With the Wind over at 20th Century Fox Studios. But she was deemed too youthful-looking and pretty for that middle-aged role (despite being 54), which went to Laura Hope Crews, so Fox producers sent her over to MGM to audition for The Wizard of Oz.
Trivia: When the characters get to the haunted forest they each have at least one kind of weapon but they are never acknowledged or used. The scene the weapons were supposedly used was the "Jitterbug" scene. Before the witch sends the flying monkeys out she tells the head monkey Nikko that they won't have any trouble catching Dorothy and Toto because she sent an insect ahead to take the fight out of everyone. The cut scene has been recently found and is available to watch on YouTube.