Precigrader - precision timber strength grading
Useful links:
Dynagrade, Dynagrade grading technology.
Lumber Stress Grades and Design Properties, a PDF-doc. covering Ch. 06 in Wood Handbook. The principles of grading is described.
MSRLPC, MSR Lumber Producers Council (North America)
North American lumber market facts, the Random Lengths
Where to find agencies to certify a mill for strength graded wood products: