What the heck is making these holes?

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Are there holes in the roof directly above these?

No holes in the roof. And I stuffed a couple of moth balls down each hole, because the holes seem to be multiplying.

 

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Sounds like your floor boards dried and the knots dropped out.

Can't be. The holes are PERFECTLY round, and the barn is really, really old (Maybe 5 or 6 decades or more.)

 

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Maybe:

Floor made with used boards. Previous holes were drilled out and plugged. Plugs are now falling out.

Clean the floor very well, till you can see the grain. Any remaining secure plugs may be visible then.

Bruce

That's a possibility! Will check it out when I go back up again.:thumbsup:

 

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Some new giant beetle species that is coming out of the melting permafrost?

LOL - we are up North, but not THAT far North!

 

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do you, or a close neighbor have chickens, or other fowl? because this could be rats. but if they are coming into your shed, there should be rat droppings inside.. what you could try, is get a pack of 4 insect fogger cans, and set them off inside the shed, let that sit for the recommended time, what ever this is will either be killed, or will flee, I'd look outside for anything fleeing that spray.. you could put down sheet metal over the floor, it's pretty cheap, and nothing will be getting in anymore, but if it's something that eats wood, you could have big structural problems.. you could also try getting a funnel, and pouring rat killer down each hole..

The rats would not have to chew their way in, as there are plenty of access points (including a big space under the barn doors). And in any case, no rat or rodent of any kind could make such a smooth hole.

 

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Can't be. The holes are PERFECTLY round, and the barn is really, really old (Maybe 5 or 6 decades or more.)

In at least one of the pics the hole(s) appear to be slightly elongated...they also look slightly rounded over at some of the edges

It would be interesting to see what the underside of the holes look like...any chance you can stick a penlight down one hole and peek down another?....see if there is debris under the holes like something (rat) chewed them from the underside...?

 

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...And in any case, no rat or rodent of any kind could make such a smooth hole...

Sure they can...look closer with a magnifying glass...you'll likely see tiny tooth marks

 

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Floorboards are supported on bi 8" x 8" cedar beams, set right on the dirt.

 

[CincyFlyer]

Got the same thing here in Indiana. Our's was caused by bumble-bees. The big black and yellow type. They are persistent little buggers.

Them's carpenter bees. Bumble bees are fuzzy, and don't drill holes. Carpenter bees have bare abdomens, and make perfect holes. All over my fence.

 

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I'm at a total loss and just want to follow along to learn what it is. The smoothness of the holes makes it very odd, also that there are so many. I've dealt with squirrels and racoons doing this to get into the attic of a house, but they only make the one hole and then they are done. Wood peckers are also bad on wood here, but I've never heard of one going inside a building before.

Is there any sign of poop anywhere? Can you spread a thin layer of cooking flower on the floor and check back for tracks?

Please keep us posted on what you find out.

No poop, but I will try spreading flour on the floor - thanks for the idea!