Dead standing Oak at 33% - how long to season?

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Amin1992

Feeling the Heat
Oct 9, 2019
334
PA, USA
Hey guys. I know typically a living Oak can take 2 years or even more to properly season once down, bucked, and split.

We just cut down an oak that died maybe 5 years ago and has been standing with almost no branches.

I took a moisture reading right at the stump, which I assume would be worst case (thickest part, lowest so water may settle downward) and it was at 33%.

Curious if anyone knows how long it takes an Oak to go from 33% to 20%. Or, has anyone taken moisture reading on a fresh, green Oak that can share? I read online from a few sources that green Oak is typically 50-80%.

I would think if living green Oak is, say, 70%, and it takes 2 years to get to 20%, that's a decrease of 25%/year, or about 2%/month. At that rate, my oak would go from 33% to 20% in about 7 months if I split and stack now. But not sure if my logic is right or not.

For comparison, I've heard others argue that Walnut takes 2 years to season. We had a similar Walnut, that was living but fell a year ago in a storm, and was laying on the ground but mostly not touching soil. A year later, we bucked and split it. I don't remember exactly but I think it had moisture levels in the 30s. Anyway, 5 months later and it was at 22%, and I didnt get a reading after that. Where I stack my wood is a bit shady, but super windy and open so I think that helps.

Thanks all for the advice.
 
Unfortunately I don't think you can make direct seasoning time comparisons like that. Seasoning time is very set up dependent so it's hard to give exact numbers. How its stacked and how much sun/wind/rain exposure it gets makes a big difference. Also, oak is notoriously difficult to season due to its high density...it just doesn't want to give up its water.

I'd take a few pieces inside, get them to room temp, then split a fresh piece and measure going with the grain. Thatll give you a true reading and its likely a little higher than what you're getting outside.

For reference I took down some standing dead red oak this past spring, around April. I'm in MA so not too far from your climate. It had been dead at least 5 years and was just a trunk. I had it split and single row stacked all summer getting backed in the afternoon sun and wind (wind is the most important thing IMO), top covered...basically ideally set up to season and it was not ready for this winter. I was getting readings ranging from 24 to 30% depending on the piece. Most of it should be ready for next winter as I split those 30% pieces a little smaller.

Bottom line - there's no easy way to say. If you want to power season it your best bet is to make a solar kiln...lots of good info on that here. If you want to go naturally just split it small and make sure it's top covered and getting as much sun/wind as possible. I'd still plan on it taking a full 2 summers though and be pleasantly surprised if it's faster.
 
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That's great to know. Thanks for sharing this. Sometimes I am jealous of my buddy with an old smoke dragon who splits Oak and burns it 3 months later, haha!

Here's to hoping it isn't terrible next year. Will have to remember to report back!
 
I always enjoy driving the back roads of PA. in the fall. Almost every other yard has a fresh pile of split wood.
My impression is, it goes from the splitter to the stove. Usually not a stack to be seen.
 
Haha now that I own a home with a wood stove, I realize there really is so much free/cheap wood around in front yards. Just have to put in the work for it!

I have no clue how people go straight from splitting to burning. Never worked well for me.
 
If you have a newer EPA stove you really can't throw green wood in or you're gonna have a bad time. It "works" in old smoke dragons but is horribly inefficient and polluting.

If you really need that oak to be ready next winter I highly suggest checking out the solar kiln threads. I think its basically the only way you're gonna have a chance at it finishing.

If you're really hard pressed lumber scraps, pallets (as long as not PT or painted, watch for nails) work. Bio bricks. Theres lots of standing dead ash in the north east too. If you c/s/s that now it'll be ready for winter. Pine too.
 
Thanks Caw for the suggestions. My wife would not be okay with me building a big plastic structure out back haha, I wish! I think I will have enough. I'm just in a pinch because I dont have a ton of room for storage (can maybe store 2 cords max on the property) and the majority of what will be ready for next winter are in the back/bottom. so I need to remove it all, stack the oak, and put the ready stuff on top haha
 
How much room do you have? I'm able to stack on blocks and 2x4s in a pretty tight space. 16' x 4' x 6' high will store about 2 cords when full. I have four on the edge of my property and then some pallets on the other side of the house. I keep about 11 cords on 1 acre without really intruding on the yard.

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Thanks Caw for the suggestions. My wife would not be okay with me building a big plastic structure out back haha, I wish! I think I will have enough. I'm just in a pinch because I dont have a ton of room for storage (can maybe store 2 cords max on the property) and the majority of what will be ready for next winter are in the back/bottom. so I need to remove it all, stack the oak, and put the ready stuff on top haha

Then I suggest you look for pine, cherry, ash. They season faster.

Also, moisture content likely does not decrease linearly in time; the decrease slows down when the content gets lower. So an extrapolation like you did will likely underestimate the real moisture content you will have.
 
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I always enjoy driving the back roads of PA. in the fall. Almost every other yard has a fresh pile of split wood.
My impression is, it goes from the splitter to the stove. Usually not a stack to be seen.

Yeah that's how it is here in town as well, everyone gets big piles of wood in the late summer and nothing left at the end of winter. It appears anyone who's a wood burner around here just has a fireplace and probably uses it evenings and weekends. Then there's me, Mr. Woodburner who heats his home with wood using an EPA stove and has over 20 cords of wood stacked around his property lol!!
 
I personally avoid oak (too long to season). If I get it I split it into wrist size splits. It seasons much faster.
Stick with ashes, maples, cherries etc.
 
As stoveliker alluded, your "25% per year" estimate is based on an intuitive linear interpolation. It's likely to look more like exponential decay. So if you dry it for 2 years, 2/3 of the drying may occur in the first half.

Here's another good source on your expected final percentage:
 
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I'm able to stack on blocks and 2x4s in a pretty tight space. 16' x 4' x 6' high will store about 2 cords when full
3 cords Caw
 
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Hey guys. I know typically a living Oak can take 2 years or even more to properly season once down, bucked, and split.

We just cut down an oak that died maybe 5 years ago and has been standing with almost no branches.

I took a moisture reading right at the stump, which I assume would be worst case (thickest part, lowest so water may settle downward) and it was at 33%.

Curious if anyone knows how long it takes an Oak to go from 33% to 20%. Or, has anyone taken moisture reading on a fresh, green Oak that can share? I read online from a few sources that green Oak is typically 50-80%.

I would think if living green Oak is, say, 70%, and it takes 2 years to get to 20%, that's a decrease of 25%/year, or about 2%/month. At that rate, my oak would go from 33% to 20% in about 7 months if I split and stack now. But not sure if my logic is right or not.

For comparison, I've heard others argue that Walnut takes 2 years to season. We had a similar Walnut, that was living but fell a year ago in a storm, and was laying on the ground but mostly not touching soil. A year later, we bucked and split it. I don't remember exactly but I think it had moisture levels in the 30s. Anyway, 5 months later and it was at 22%, and I didnt get a reading after that. Where I stack my wood is a bit shady, but super windy and open so I think that helps.

Thanks all for the advice.

So to answer your question regarding seasoning. This wood will no quite be ready for this fall. Wood will not average 2 or 3% per month. In fact I did some checking of MC in my stacks a number of years ago. January and February you splits will louse less than .75% MC per month while in the summer it can be as much as 2 to 2.5% MC per month. This being said it will also vary on how much its already seasoned. The splits will drop MC faster when just split EXAMPLE.. going from 38%MC to 33%... It will be slower as the MC drops so as you get closer to 25% it takes longer to get it to 20% even though in both cases you lost the same 5%. As the wood losses MC its a slower process...
 
Thanks all for sharing your thoughts, means a lot! Ya, wasn't sure if the moisture release was linear or not. Will read up on the exponential decay for my estimations. Also, I have 1.3 acres but the way my land is laid makes it quite difficult to lay more. It's a long, rectangular, thin lot, on a slope, and the wife doesnt like seeing too much stuff around. Also surrounded by dense woods except where the septic runs. I've got 3 racks, each a face cord, plus room for a few pallets. Gets me to around 1.7 cords storage.

Can I ask you guys, I've got this oak laying down now. Is there any harm in waiting until spring to buck and split and stack? It is currently laying in about 1 foot of snow and I hate dealing with bucking in that, plus transporting 200 ft to my racks will be difficult. Also hate working in the mud but rather do that than wait all the way to summer. Thanks for the tips and input!
 
The sooner you split and stack it the sooner it will begin seasoning. We all have to work with the elements.
 
Thanks all for sharing your thoughts, means a lot! Ya, wasn't sure if the moisture release was linear or not. Will read up on the exponential decay for my estimations. Also, I have 1.3 acres but the way my land is laid makes it quite difficult to lay more. It's a long, rectangular, thin lot, on a slope, and the wife doesnt like seeing too much stuff around. Also surrounded by dense woods except where the septic runs. I've got 3 racks, each a face cord, plus room for a few pallets. Gets me to around 1.7 cords storage.

Can I ask you guys, I've got this oak laying down now. Is there any harm in waiting until spring to buck and split and stack? It is currently laying in about 1 foot of snow and I hate dealing with bucking in that, plus transporting 200 ft to my racks will be difficult. Also hate working in the mud but rather do that than wait all the way to summer. Thanks for the tips and input!

I just finished up my stuff this past weekend, even though its crappie out. Me personally I don't like wood sitting on the ground as it stays wet. Seasoning only starts when the wood gets split, so the longer it sits the longer it will be before its ready to burn.
 
Probably a couple of years to season under 20% moisture.
 
Thanks all for the advice. Either way, I need to wait for the snow to melt, as all this snow turns this 8 hour job into a 24 hour job, as I'd have to switch from a wheelbarrow or wagon to carrying by hand in a firewood carrier, trudging through the snow... here's to hoping this warm weather persists!
 
It's likely to look more like exponential decay. So if you dry it for 2 years, 2/3 of the drying may occur in the first half.
And the reason has something to do with the fiber saturation point. For most woods this would be around 30%. Above that the
free water escapes easily through capillaries. Below that bound or hygroscopic water escapes across cell membranes, and takes far longer.
 
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Thank you for explaining and thank you everyone for the advice
 
And the reason has something to do with the fiber saturation point. For most woods this would be around 30%. Above that the
free water escapes easily through capillaries. Below that bound or hygroscopic water escapes across cell membranes, and takes far longer.
Does rain (wet wood surface), reduce the escape across cell membranes?
 
Does rain (wet wood surface), reduce the escape across cell membranes?

Yes, temporarily, until the surface is dried off again. Hence the need to cover your stacks.
 
Does rain (wet wood surface), reduce the escape across cell membranes?

any time your wood takes on water will slow the drying process... wood will only be able to loose a certain amount of moisture at a given time