h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

"If they are dark and discolored, this means the wood has rotted because of exposure to the weather for at least six months, and is therefore seasoned."
If the wood actually rots it has been exposed to too much moisture and is probably mouldy and hazardous to asthmatics as well. Seasoned wood will be dark and discolored, but beware actual deep rot.
Judging the quality of firewood is very difficult, and the best way indicator is weight contra size. This takes practice, but it's what works. You can also purchase instruments that have to metal spikes and meassure the resistance of the wood to electric current. But they are probably expensive, and take practice as well.

perhaps "rotted" was not a good term to use in describing the darkening of the wood then.

I'd heard that term used by someone who was describing what's actually happening to the wood when it discolors, so went with it even though I *knew* there was a defininte difference between that dark discoloration and truly *rotted* wood. The truly rotted stuff will crumble and not be much good at all for firewood.

I've bought wood in the past that had mold growing on it in spots, although it was because of excessive rain and humidity while the wood was being seasoned, and not because the wood was truly rotten. The weather had simply been so wet that the mold spores in the air had made themselves at home on this nice solid organic matter.

You're quite right that determining if the wood is seasoned properly is best determined by weight for size. I've never seen devices that can determine the actual moisture content of a piece of wood perhaps we just don't have them here in the states.

The discoloration probably _is_ rot, but its only on the surface, so, yeah, saying the wood has rotted was slightly bad. Not very bad though. Even well seasoned wood can have mold on it, yes, and it's not a problem unless you are allergic or believe the current mold scares. (That might be good science some day, just not yet.)
I've only seen the device used on a consumer show where they examined wood sold in Norway. It had two prongs and was hammered a bit into the wood, the guy using it was a government official... I don't think checking the moisture content of firewood was his whole job, but it was part of it.

Yeah, I am a little allergic to mold - at least apparently I am since we had the moldy wood last year and I spent the better part of the season with a headfull all the time.