Log with beetle larvae

[Jacques Gagnon]

You have to get the inside of the wood up to 133 degrees to sterilize it. Sun exposure won't come close. Usual I get my kiln box up to 150 so the heat soaks in.

The temperature that Richard mentions is the one used in an internationally recognized phytosanitary standard for treating wood products. The goal is to submit the entire piece of wood to a temperature of 133F (56C) for 30 minutes. The key here is reaching the target temperature down to the core for that specified period of time. The time required will be a function of factors such as shape (thin rectangles will require less time than square cubes for example), initial temperature, moisture content.

In the case of interest to the OP, mortality of the larvae will be a function of various factors; drastic changes in the larvae’s environment (e.g. cutting open the burrowed area will drive the moisture level down) will negatively impact survival rate.
Heat will deal with those larvae protected by a certain amount of wood/frass. Being able to eliminate the insects that are still active would prevent further burrowing, hence less damage to the wood.

[Alex Zeller]

If you have the room and since you own a mill I would look into building a solar kiln. Around here you'll risk getting powder post beetles in the wood before it can dry unless careful. Wood has amazing insulating properties. Just a few wood chips from a chainsaw is enough to keep ice from melting until the middle of summer around here. I suspect the driveway idea could work if the nights are warm and you went out several times and flipped the boards during the day. Last summer I had some QSWO that had worm holes like those in the sap wood. The kiln killed them. It was a feature that didn't work with the project I was making though so I culled the stuff with the holes.

[Justin Rapp]

If you have the room and since you own a mill I would look into building a solar kiln. Around here you'll risk getting powder post beetles in the wood before it can dry unless careful. Wood has amazing insulating properties. Just a few wood chips from a chainsaw is enough to keep ice from melting until the middle of summer around here. I suspect the driveway idea could work if the nights are warm and you went out several times and flipped the boards during the day. Last summer I had some QSWO that had worm holes like those in the sap wood. The kiln killed them. It was a feature that didn't work with the project I was making though so I culled the stuff with the holes.

I don't own a mill, it was a small log, I used my bandsaw to mill the lumber.