Reduction of MC in Dry, Windy Climate

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wjohn

Burning Hunk
Jul 27, 2021
237
KS
I cut down some dead standing Honey Locust about a month and a half ago. These trees had probably been dead for 2+ years. When I checked MC after cutting and splitting several samples, I was getting 40-48%. Since then they have been in the new wood shed for about a month, getting full sun and tons of N/S wind through them. No precipitation to speak of. A lot of nice cracks have developed in the splits and even whole logs sitting in the wood shed. The MC after freshly splitting these pieces again is now 22-28%.

Is this reasonable or should I be doubting my MC tester? The way it's going, if these numbers are accurate, I should be able to burn this stuff in another month, so I'm suspicious. Heck, I could probably burn it now if I didn't have covered seasoned wood from the last several years stocked up.

I did check a few of the pieces I had left sitting on the ground after cutting, and they are still showing 40%+ MC so it doesn't seem to be the tester. Please do keep in mind we have low humidity and lots of sun and wind compared to where many of you are located. Just curious if this quick drydown is feasible.
 
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I can tell you that in good drying conditions like you describe, freshly c/s/s/covered wood will loose moisture quickly, however, the drying process slows down after this. So you can drop 15-20%MC pretty rapidly, but to squeeze that last 10% out to get it below 20% takes a lot longer. So don't expect it to continue to dry out so quickly, and I doubt it would be ready to burn this winter.
 
I can tell you that in good drying conditions like you describe, freshly c/s/s/covered wood will loose moisture quickly, however, the drying process slows down after this. So you can drop 15-20%MC pretty rapidly, but to squeeze that last 10% out to get it below 20% takes a lot longer. So don't expect it to continue to dry out so quickly, and I doubt it would be ready to burn this winter.
Challenge accepted! Ha. Yes, I understand that the rate of moisture loss decreases as the MC goes down, and will eventually level off at some equilibrium value of greater than 0% after a long time. I will keep checking throughout the winter and see what it drops down to. Thanks for confirming what I've seen so far is reasonable, and keeping my hopes in check on burning some of this stuff yet this winter.

Here's a pic showing some of the cracking on the ends so far.

20211212_162039.jpg
 
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I cut down some dead standing Honey Locust about a month and a half ago. These trees had probably been dead for 2+ years. When I checked MC after cutting and splitting several samples, I was getting 40-48%. Since then they have been in the new wood shed for about a month, getting full sun and tons of N/S wind through them. No precipitation to speak of. A lot of nice cracks have developed in the splits and even whole logs sitting in the wood shed. The MC after freshly splitting these pieces again is now 22-28%.

Is this reasonable or should I be doubting my MC tester? The way it's going, if these numbers are accurate, I should be able to burn this stuff in another month, so I'm suspicious. Heck, I could probably burn it now if I didn't have covered seasoned wood from the last several years stocked up.

I did check a few of the pieces I had left sitting on the ground after cutting, and they are still showing 40%+ MC so it doesn't seem to be the tester. Please do keep in mind we have low humidity and lots of sun and wind compared to where many of you are located. Just curious if this quick drydown is feasible.
Locust is great firewood! Burns perfect on a hot bed of coals. I like to save it up for those bitter cold overnight burns.
 
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I would split all those bigger pieces and give it another year anyway.
Ah, I explained that in my post in the woodshed thread, but not here in this thread which is most unhelpful of me. I just loaded a bunch of cut logs at the front of the woodshed just to get some weight on it so it doesn't blow away. I'll split them as time allows but they sure are losing moisture so far as-is. The stuff towards the rear is all split or 4-5" diameter or smaller rounds that I don't intend on touching again until I burn it.
 
Parents just got back from KS. The relative humidity one day was 8%. Good air dry air and some sun. What temp was the wood when you measured. That makes a difference in the reading.
 
Parents just got back from KS. The relative humidity one day was 8%. Good air dry air and some sun. What temp was the wood when you measured. That makes a difference in the reading.
50-60 degrees outside air temp but the wood may have been a bit warmer than that since it had been in the sun. Honestly, that's about what it would've been if I had brought it inside the house.

You know very well how dry and windy it can be out here!
 
For a visual of what windy and dry can look like. Taken today. I grew up in this house on the KS/CO border. One dust storm was so bad we had dirt drifts 3-6’ high. I believe that was 1988.

73D72445-8EA4-4132-8A2D-C3F55229C612.jpeg