Trees for profit

[Al Stangenberger]

Larry Caldwell (larryc at teleport.com) wrote:

: By strength I was referring to extreme fiber in bending strength.  Oak is
: stiffer (higher modulus of elasticity) so isn't so springy.  Oak has a
: higher compression strength perpendicular to the grain, I don't know about
: parallel to the grain. 

According to the Wood Handbook (USDA Ag Handbook 72), coastal Doug Fir has a 
maximum crushing strength parallel to the grain of 3780 psi green, and 7240 
psi at 12% moisture.  White oak is 3560 psi green, and 7440 psi at 12%.

However,

1.  Those are averages, no mention of confidence limits. Given wood's
    natural variability I don't know if the differences are significant.
2.  There are lots of other values for different species of oak, which would
    give completely different conclusions.  Same for Douglas-fir (various
    interior populations).

--
Al Stangenberger                      forags at nature.berkeley.edu            
Dept. of Env. Sci., Policy, & Mgt.    145 Mulford Hall # 3114
Univ. of California at Berkeley       Berkeley, CA  94720-3114
(510) 642-4424  FAX: (510) 643-5438