A free Wood Handbook published by the USDA Forest Service Laboratory is avail for download (PDF 14.3 MB)..... It's a very large file.
Wood as an engineering material. General Technical Report 113. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 463 p.
Or of course, you could purchase a copy via the government webiste or Lee Valley Tools.
Thought I share this little free hidden gem on the Internet.
Mike