Do I Trust This Moisture Reading?

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I’ve got 10’-15’ log lengths of various hardwoods (oak, maple and birch) that I get from a logger friend. They’ve been sitting out since the spring (not sure when they were felled or came down) and I’ve been getting thru them slowly due to a busy toddler-centric schedule.

It was a nice day out yesterday, so I decided to do a little bucking and splitting for next year. I’m onto my second 9’ diameter holzhausen.

Anyway, one of the lengths from yesterday was, I think, some birch, about 4”-5” in diameter, so not such a big one. I split some with an ax yesterday, (is birch stringy or what?) and didn’t take a moisture reading, figuring no need until next spring when I do re-splits, but this morning I split some more and checked and I got readings of between ~14-17%.

Are these readings to be trusted? Are there some rules of thumb I’m missing or should keep in mind when checking splits like this? I would have thought maybe because it’s birch, although a week ago I was getting 18-21% on some red oak.
 
If they were frozen or cold they can read low. Bring a couple in the house and warm them. Then split and test.
 
Put the meter into the palm of your hand. Don't draw blood. Avg person is low 30's. check some trim thats in your house for decades. Should be around 7%. These inexpensive meters are for guidance. Not absolutely accurate.
 
what they said above.....plus, bring some in spit and put a fan on them. Ive had great luck with this.
 
Some meters come with a calibration circuit in the cap.

Oak that has not been split will not be below 20 pct.

Are you measuring along the grain on the freshly split surface? (Not in the cut surface?)

Indeed temperatures matters. They are calibrated for using on room temperature wood.
 
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For any standing dead wood, test it. Don't assume it's dry.

I just had a large half of a big leaf maple cut down. It's been dead for 2 years. At the base it's about 24" in diameter. I split some of the wood from higher up that was around 12" thick and tested the wood for moisture content. Cold, it comes in at 47.4%!! I'm letting it warm up to room temp and will test again. This wood definitely will not be ready to burn for at least a year in spite of being dead.
 
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Tested again after the split was in the house for 6 hrs. It is now at 50% or higher because this is as high as the meter reads. I also weighed it (8.4#) and will leave it indoors to track the weight loss over time. Its weight is half water!
 
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