I was considering using a circular saw, but I was thinking... for cardboard, naa - but I guess it's really not a bad idea! That's great yours was free, especially wood like that. I will check FB at times, sometimes there's a decent free posting or 2.
Plastic containers would make more sense for the wood. Here's some directly from the box, I prefer them smaller so I'll split them at least once. They're really easy, like the tree I recently had taken down in my yard. One box was labelled May 2019, but it burns well, no hissing sound from moisture. The other box had no label but the wood appeared to be seasoned longer.
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