The conventional method for determining lumber strength depends
on visual evaluation by lumber graders which often results in
undergrading of lumber. Nondestructive proof testing is used less
often and provides for only estimates of elastic moduli of elasticity
and rupture. The evaluation of nondestructive variables such as
proportional limit (PL)...
Workable log grading systems are needed as aids to marketing timber and other phases of forest management. How can on system be evaluated and compared with other systems. The question of comparisons arose soon after the Western Pine Section of the Forest Service's National Log Grade Project was established in...
