By this point, it's becoming very apparent that the costuming department of the film have a lot of things to answer for. Poor Ray Bolger in the scarecrow outfit was their next victim. We hope he liked the looks of his character, because he was seeing it for the entirety of the next year every time he looked into the mirror.
The scarecrow effect on Bolger's face was created using a combination of makeup (there's the makeup department trying to kill people again) and some very primitive prosthetics. These two elements somehow came together to create deep and lasting lines on the actor's skin, which mostly faded away after a long time, but according to Bolger there were some that remained there for the rest of his life. It's one thing to play a part that you're known for forever; it's quite another to actually look like that character for the rest of your days!