When a land surveyor locates and establishes points between two survey stations, that act is called ranging. There are two conventional methods of ranging: the direct method and the indirect method.
Direct Ranging Method
This is applicable to situations where the ends of the survey stations are inter-visible. Meaning, you can see point X from point Y and vice versa.
Indirect Ranging Method
This one is for survey stations that aren’t inter-visible. Ranging rods are set up between the two points or survey stations, thereby guiding the surveyor or any viewer on where the straight boundary line lies.
Land surveyors typically use range poles or ranging rods to mark points and survey lines.