If you already have the metal strips, you need to be careful if you're buying wood that already has the gooves cut. Some manufacturers metal strips are a little different than others and require a different depth for the groove.
I would bet that it will be from a tree that is quickly grown
Not sure how a tree is quickly grown, but I can assure you that the red oak in the big box store is the same, if not better, than you would find at any lumber yard or supplier of bed wood.
You can get the bit to countersink the bed-to-frame bolt washers at the big box store, too. Look for a 1 /9/16" FORSTNER bit.
