Firewood seller's know instantly, as soon as the question is asked.
If a buyer cannot look at wood and determine a basic level of aging and dryness, they will ask "is it seasoned?".
"Why sure it is, ready to burn".
Fireplace firewood bought in the spring here in Louisiana, will most likely be racked until fall, allowing most folks that burn it in a fireplace, to be satisfied with how it burns come November, especially with a gas igniter. That gives most fireplace firewood seller's half a year to not have their claim of "seasoned" come into question.
Check with your supplier, for wood that is ready to use today. Tell him you are using it for a wood burning smoker. For use today. If you just bought "fireplace firewood", and your supplier can't get you truly seasoned wood, then find someone else.
I cut my own oak and pecan from trees on my place, mostly large limbs that come down from storms. Happens regularly enough to keep me in wood without having to buy, and I am grateful for that.
The pictures below are from a rack that holds pecan that I cut in August of '19. It has less than 8 months of seasoning. It is exposed to weather, uncovered, and needs to be split.
This pecan rack still needs another 4-6 months to be ready. Took the pictures today.
But you can see the cracking starting from drying, even without being split.
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