Moisture Movement in Log

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WarmGuy

Minister of Fire
Jan 30, 2006
519
Far Northern Calif. Coast
A while ago, someone on this forum said that there was very little or no lateral movement of moisture in a piece of firewood. That is, the moisture moves out the ends.

If true, then an unsplit piece of wood will dry as fast as a split piece, and the presence of the bark will have no effect.

What do you think?
 
I can't agree much with that. It dries much faster after it's split and stacked. Unsplit rounds of same wood cut at same time never dried as well as that split/stacked. What was said is true of connifers, though. Decidous tree wood has lateral channels for water/food movement. IMHO.
 
WarmGuy said:
A while ago, someone on this forum said that there was very little or no lateral movement of moisture in a piece of firewood. That is, the moisture moves out the ends.

If true, then an unsplit piece of wood will dry as fast as a split piece, and the presence of the bark will have no effect.

What do you think?

A little confusion here. Wood movement refers to shrinkage. Wood shrinks along the grain much more than across the grain. Exposure of raw wood without bark increases drying rate. The moisture can move across the grain, along the grain or around, but it does not move well through the bark. I suppose naked rounds would dry faster, but ... the kids ... you know... Seriously the farther the moisture has to travel through wood the slower it will dry. Kindling dries in days, but I have a Torrey Pine round, 16 inches in diameter, cut 1988, still at 40% moisture in the middle. But that's a story for another day.
 
Split pieces of wood expose more surface area and therefore they dry more quickly.....no two ways about it. What that person was saying was that the shrinkage occurs in the lengthwise direction but the drying is pretty much proportional to the surface area exposed.
 
OK, thanks for that info.

This year I'm going to weigh each of the logs in the photo monthly to determine how long drying takes in my environment. Logs D and E were equivalent in size, E was split. F was wood from last year that was left out in the rain, but will now be covered.
 

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awesome experiment!

ive noticed that splits dry faster.
the bark is there to protect the tree during its life, and does so well into its early stages of death.

Not just that though, If you take a round, and split it into 4 splits.

each split only contains 25% of the moisture of the initial round, this would lead me to think that it will 'loose' that moisture in 25% of time that the entire piece would have, regardless of any bark right?

then figure in surface area, the fact that its likely stacked now that it is split...

interesting experiement.
Ive got a batch of green wood right now, ( not real green, but seasoned less than a year)
im having to split it into fairly small splits, and im stacking them on the hearth on either side of the wood burning insert.
the splits dry out to a useable state within a couple of days.






WarmGuy said:
OK, thanks for that info.

This year I'm going to weigh each of the logs in the photo monthly to determine how long drying takes in my environment. Logs D and E were equivalent in size, E was split. F was wood from last year that was left out in the rain, but will now be covered.
 
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