Tom had tried to figure out what type of hair he had but he hadn't really thought about it before, seriously why would anyone know what type of hair they had, all he knew was that he had hair and when he played football or rolled around in the mud that it got dirty and he had to wash it.

Tom had picked up his leaves and decided to do the spell. "Pulveris" he then did the wand movement and was happy when it worked, not he had to think of what type of hair he had, how was he supposed to know.