Trriviia puzzle, kinda wood-related
Credit for this goes to the boys at Car Talk, but I'll take any blame for errors in its retelling.
Tom and Ray were at an antique auction, and one item being auctioned was a red painted wooden child's sled, which the catalog claimed was made by George Washington. Tom and Ray decided to inspect the sled, and it seemed to their untrained eye to be about the right age. On the underside of one of the slats was carved "G. Washington, September 10, 1752". That would make Washington about 20 years old when it was made, and the workmanship was that of a relatively inexperienced amateur.
When the bidding got to this item, one person stood up and proclaimed that the sled was a fake. It was. How did he know?