When some ways back I built those oak steps, I had obtained the material from a local tree guy who air dries what logs he can allocate and slice up himself on his portable sawmill. In addition to the oak I had gotten two pieces of wide beech because they were cheap and I’d not worked with beech before. These particular pieces, I’m not sure why, after I brought them home and lay them fallow for two years, demonstrated great warping and cupping – as if perhaps they were not as dry as he thought. Next time I’ll being a moisture meter, but at the time I was not so sophisticated.
I decided that I’d be a frugal miller and see if I could get any utility out of them, beyond that of firewood. The smaller piece was about six feet by 11 inches by one inch thick. I cut it in half to reduce the impact of it not being straight but rather vaguely like a bow shape and put the halves seven times (sounds biblical, the halves seven times, or Talmudic, or alchemical, or) seven times the halves were put through the thickness planer, and though this cost them almost 5/16ths of their thickness most of the cupping/arching was removed. With a straight edge and tablesaw I took out the long curves and obtained the shelves you see below.
It was a harder wood than I thought, had to pre-drill the holes for screws (usually I don’t use nails of screws, but for rough carpentry I make exceptions). The blond verticals are hackberry. The gourds on the top shelf are very happy with the setup.