[David G4EBT]

The holes aren't holes where the woodworm burrowed into the wood, but 'flight holes' where the 'woodworm' larvae pupated, turned into bettles and left the wood, having burrowed up and down in their long larval stage for perhaps uo to 4 years. It won't do any harm to soak it in rentokil or whatever, but the culprits will have long ceased to have been in residence. Inside, the wood will be honeycomb of course, with little strength.