Staff compasses are attached to sockets mounted on "Jacob's" or "Jake" staffs, which have sharpened ends that can be thrust down into the ground. Since the compass is held steadier (and they are usually larger), more accurate work can be done than if a hand compass is used. The wooden compass is evidentially very old -- the manufacturer gives his address as "Fanueil Hall, Eaft end of Boston", with an "f"-like "s". From the Leonard's Mills Forest and Logging Museum.
In the present times timber has become so valuable that formal surveys or often called for as even a single tree may have sufficient value so as to create an argument, but in times past this was not the case and so equipment like this was used to establish 'quick and dirty' lines for harvesting purposes.