The wood must be dry and free of oil. Generally the finish sanded stock is dampened and quickly dried to raise the grain (aka "whiskering"). The torch is applied to the wood, scorching the end grain and leaving the flat grain only slightly darkened. If done correctly, this process results in a depth of figure that is unobtainable with any other method. The only thing that I have found that comes close is aqua fortis heated with a heat gun.
I knew both Hal Hartley and Harry Creighton well. Both were extremely fine men that I am proud to have known. Harry was a fine baseball player and photographer, while Hal was an occasional writer and former boxer. I do not know whether Xausa is aware that Hal was the former amateur boxing champion in North Carolina before WWII (I think probably middle-weight).
Hal cut a lot of sugar maple in the Blue Ridge mountains surrounding his home in Lenoir, NC. Some of the maple found there is superb, and Hal found some of the best. He was not adverse to using maple and other woods from other sources, often purchasing product from suppliers in Wisconsin and Pennsylvania.
