Walnut is always a unique market. So- u both are correct. Walnut is often uniquely sent to China. With some white oak. *side note for fun.... some of it sunk to bottom of ocean for the pressure which I believe impacts the color/grain & pattern of it on veneer quality walnut.
Iowa & a few belts in MO, IL & southern MN/WI grow the best walnut on earth!
for building market: lots of oak, cherry, hickory, etc etc. that’s for floors, cabinets, trim or other things inside houses. then u have soft maple for furniture. Junk for pallets of course. List of wood/species & uses for Midwest timber being used in building industry is solid & vast.
The one item iowa lacks is stuff like plywood mills .... that stuff doubled in price & as some of us sit on forested farms - I don’t think there’s much option except to buy it - sucks!!
some folks on here have had timber dried & milled or milled themselves & done awesome things. I wish I had that talent!!!