Stewart Holbrook was a lumberjack-turned-writer whose first book was Holy Old Mackinaw: A Natural History of the American Lumberjack (ISBN 1112559892). That book, first published in 1938, includes a Loggers Dictionary which defines some of the jargon of the lumberjack. The following list is excerpted from that and other sources:
Barber chair: a tree which splits upward along the grain during falling.
Batteau: a type of boat used on river drives in the eastern United States
Branding ax: a tool used for marking ownership of a log
Buck: to cut a tree into lengths after it has been felled
Bucker: one who saws trees into logs
Bullcook (also known derogatorily as the crumb boss): a boy who performs chores around camp, such as sweeping up the bunkhouse , cutting wood for fuel, filling wood boxes, and feeding the livestock
Drag day: the point in the work month when a man can get an advance on his wages
Driving pitch: high water suitable from driving logs down a river
Duplex: a stationary engine that both assembles (yards) and loads logs
Gandy dancer: a pick-and-shovel man
Gin pole: a short spar, used for loading and unloading logs
Gyppo: contract work (or worker), measured by the inch or bushel for example, or by the mile in the case of a truck driver
Hardtack outfit: a company running a logging camp which provides substandard food (derived from the cheap and long-lasting cracker or bread of the same name)
Hayburner: a horse
Highball: to hurry
Hiyu: plenty, large, enough
Homeguard: a long-time employee of a company
Hoot-nanny: a small device used to hold a crosscut saw while sawing a log from the bottom up