Smoking can cause a yellow mustache due to the tar and nicotine in cigarettes staining facial hair. It can also slow down hair growth and make the mustache appear dull and unhealthy.
He used wax.
No doubt. You didn't say what color his mustache was originally, but many men's staches become yellowish with age, and there are certainly other causes as well.
They probably can't turn yellow, but some of them are naturally yellow..........
His hair is brownish black and looks a little greasy.
why does wheat turn yellow when it grows in the dark
Cucumbers turn yellow due to overripening, lack of nutrients, or disease.
Fire
Pickels do not grow a mustache -.-
Latex gloves sometimes turn yellow because of your hands. The oils and fatty acids on your hands breaks down the latex and can turn the gloves yellow.
can you use what on your mustache
To dress up like The Lorax, you will need an orange costume or clothing and a yellow furry mustache. Add a yellow t-shirt or accessory to represent the character's yellow eyebrows, and consider wearing a brown hat or headband to mimic his brown eyebrows. Finish the look with some colorful truffula tree accessories.