Teredo-Bored Petrified Wood
STATE FOSSIL. The state fossil of North Dakota is the 60-million-year-old Teredo- (ter-Ee-doe) bored petrified wood. Teredo-bored petrified wood got its name because little clams called “teredos” drilled tiny holes into the wood before it fossilized. Minerals filled in the cells of the wood as it decayed so that it looked exactly like the wood that had been there in the first place, except it was now stone.