How many borer holes can a stave have before it is ruined

It all depends on where they are, how big they are and how deep they go. Pics would help.

One powder post beetle hole and your wood is probably toast.

Here is what they do when they get in wood. This piece of firewood was split to show the damage with the bark side to the right of the picture.

   

I have an exploded hickory bow picture that I thought on making it that a couple of tiny pin holes wouldn't matter, it did. You can see the bug trail in the center of the picture. It has the segmented pieced of bug do-do in a row.

 

Wood wasp larva holes aren't as serious if you can work your way down to sound wood.

Powder post beetles go in the top of a log and come out the bottom.

I can't post pics all I have is a cell phone.think these are wasp I have four or five hole in the area I have marked out for my bow they go down about 1/2 " a then make a 90 for about and inch and are about a 1/16 in dia. Or smaller

Thank yall