Moisture content and seasoning

[Sundial Colin]

When drying 'left overs' for the log burner I've become interested how dry the timber can get. If you leave logs on top of the log burner for weeks to really dry out will it only be water that evaporates or does the timber itself (cellulose etc) evaporate? By weighing, I'm surprised how wet the timber is. Any comments?

 

[ED65]

It'll be almost entirely water that is lost by heating. The only other stuff that comes out of most woods are various compounds, referred to collectively as extractives, and these are in such small quantities you wouldn't be able to weigh them with a standard scale.

I presume you know no matter how dry you get the wood it will absorb water from the air when it's removed from the heat source? It'll take on water until it's at equilibrium with the surroundings, same as commercially kiln-dried or air-dried timber although I may remain slightly drier than air-dried.

 

[Beau]

Yes just water and lots of it. You might find this discussion interesting http://arbtalk.co.uk/forum/firewood-for ... sture.html