Buckeye leaves are grown on buckeyes trees, which is the official tree of the state of Ohio. Why do Ohio State players have stickers on helmets? History explained You guessed it: Tradition.

For decades, the buckeye leaf has marked the journey of Ohio State football champions, one sticker at a time. Some players’ helmets are almost completely covered in buckeyes. Each one serves as ...

As noted by The Columbus Dispatch, Ohio State's helmets include stickers that have a buckeye leaf on them. Buckeye leaves are grown on buckeyes trees, which is the official tree of the state of Ohio.