Works for baseball bats. I see no reason why it couldn't for a guitar neck. Though I, too, have never seen one.
Ash, black - 540 kg/cu m
Ash, white - 670 kg/cu m
Maple - 755 kg/cu m
Mahogany, Honduras - 545 kg/cu m
Mahogany, African - 495-850 kg/cu m
"For me, I think the only danger is being too much in love with guitar playing. The music is the most important thing, and the guitar is only the instrument." Jerry Garcia