It's called Ogham. The symbols were called after various trees and plants. There are hundreds of Ogham stones in Ireland - mainly in the south western part. The plants influence a system of writing. The symbols are scratched into stone.
Technology progresses and the symbols are cut into pieces of wood.
I can't accept any hint of prescience here. I love my IBM-compatible. This Ancient Scripts page gives a good overview of the symbols themselves, with examples in three styles. Credit is given to Curtis Clark for his ogham font. Eloquence and Ogham has more information.