The economics of sawmilling are absolutely brutal, and everything is done for profit maximization on every tree harvested. Sometimes perverse incentives will drive things like eg the price of 7' studs surges so all the 14' 2x4 or 2x6s are cut in two, or in an extreme example if the price of chips surges enough then maybe perfectly good lumber would be chipped instead of sold as lumber (this happened briefly in the 80s if I recall correctly)
To go over how from seedling to end product every single part of the usable tree is used to maximum economic advantage would take more time than I have available, but suffice it to say that in Canadian lumber, plywood, osb and paper there is as close to zero waste as is humanly possible.
Also, as a footnote, there is a lot more thought given to future harvests, environmental concerns (carbon capture, riparian areas etc) and social license (work with first nations, community involvement, worker safety) than the average person would believe.
To go over how from seedling to end product every single part of the usable tree is used to maximum economic advantage would take more time than I have available, but suffice it to say that in Canadian lumber, plywood, osb and paper there is as close to zero waste as is humanly possible.
Also, as a footnote, there is a lot more thought given to future harvests, environmental concerns (carbon capture, riparian areas etc) and social license (work with first nations, community involvement, worker safety) than the average person would believe.