Are the wood fibers in fiberboard & wood chips in chipboard by-products of other wood-working?

I live in the heart of pine timber country here in east Texas and I get to smell the stinking saw mills too. When they plant pine timber, they plant the trees very close together. About 7 - 10 years later, they thin the trees and use those small trees for chipping, which makes the products you are referring to. Later, they thin the timber again and do the same thing. The last timber harvest is for 2x material, plus the scraps are used for chipping. So 2/3 of the planted trees are chipped and the remaining 1/3 is for traditonal lumber. Of course, all of the above has been genetically altered to produce fast-growth timber at the expense of wood density. So our countryside has lost most of our forests and hardwoods in exchange for tree farms. Here's what you see: 500 acre clear cut, 500 acre burn and replant with erosion, 500 acres of densely packed small trees, ......thinned trees,.....thinned out again trees with lots of briars,......mature trees ready for harvest. By the way, no branches reach the mill. That is left to be burned or rot to provide nutrients for new saplings since it is not profitable to haul branches. Much is wasted, believe me.