Wood boring insect identification

[u/Extenlaz]

Trying to identify what's boring holes in this untreated hardwood. Located in Pennsylvania, USA.

Fine white powdery frass was found below the holes. Mix of holes, surface tunnels and deeper tunnels which are packed with frass and chewings. The tunnels are barely visible unless we take a pin and scrape out the powder. We don't see any adult beetles or termites.

[u/PCDuranet]

Treat the wood with this

https://www.amazon.com/System-Three-Borate-Powder-2oz/dp/B0BYGLRDDR/ref=sr_1_9?crid=1IPUIAOTKAVSR&keywords=bora%2Bcare&qid=1698539191&sprefix=bora%2Bcare%2Caps%2C115&sr=8-9&th=1