Why These Lengths?

Sawmill, Minneapolis, ca. 1918

Minnesota Historical Society Photograph Collection, HD5.5 r11 
Because the lumber camp took orders from the sawmill.

Mills placed orders with either logging companies or middlemen. The orders asked for specific log lengths to meet the sawmill's needs. Thus lengths varied at times from less then 12 feet to more than 20, though normal cuts were 16 feet to meet normal lumber needs.