What organization is the "Authority" in wood design and construction? What I mean by this is who is the equivalent in wood design and construction as AISC is to steel design and construction?
I would say the American Wood Council, as they are the publishers of the LRFD and ASD design manuals. But, as stated above, there is no one governing body, not that AISC is the sole answer for all things steel.
Most Building Codes require that wood design meet the requirements of the "National Design Specification for Wood Construction". The N.D.S. is an ANSI standard, ANSI/AFPA NDS-2001.
The standard is developed mainly by the American Forest & Paper Association. AFPA is made up of different associations in the lumber industry. AITC APA, as mentioned by a previous reply are members of AFPA along with other groups such as the Western Wood Products Association and the Southern Forest Products Association.
I don't think there is any direct involvment between AFPA and the Forest Products Laboratory in Madision, although there maybe FPL staff member both on the ANSI commitee and the AFPA technical commitees.
Since the FPL is one of the leading wood research labs in the world,the N.D.S. is based on a lot of FPL research.
The governing wood code is that referenced by your governing legally binding general building code. Florida building code for instance references the NDS.
The 2005 National Design Specification for Wood Construction (2005 NDS) was approved as a American National Standard on Jan. 6, 2005. The designation from the American National Standard Institute (ANSI) and the American Forest and Paper Association (AF&PA) as ANSI/AF&PA NDS-2005.