That's Ohio, for those that don't know. The Buckeye tree is very common to the entire state, and its nut resembles the eye of a deer. The native Americans that lived in this area named the tree "hetuck" based on this resemblance.
Our Buckeye tree was given to us by my parents in 1980, as a seedling in honor of the birth of our first child, Kara.
*Buckeye seed photo from http://www.extension.iastate.edu