Every licensed land surveyor in a PLSS state eventually deals with a Corner Perpetuation & Filing (CP&F) form. These documents are the legal record of a survey corner's physical condition and location — and reading them fluently is foundational to pre-field office work. Here is a field-by-field breakdown.
Township, Range, and Section Header
The top block of any CP&F form carries the PLSS description: Principal Meridian, Township (T), Range (R), and Section number. In Idaho and California this block is standardized by statute. The corner type — Quarter Corner, Section Corner, Meander Corner, Witness Corner — appears immediately below. A notation like "NE¼ cor, Sec 14" refers to the northeast quarter-section corner of Section 14, common to Sections 11, 13, and 14.
Tie Bearings and Distances
Ties are measurements from the found monument to nearby accessory objects — utility poles, fence posts, trees, iron pipes, or concrete monuments. Each tie carries:
- Bearing expressed in quadrant notation (e.g., N 47°23′ E) or full-circle azimuth
- Horizontal distance in feet (or chains in older records)
- Object description (power pole, 12″ pine, BLM brass cap, etc.)
- Optional: stamping or tag number on the object
A field crew recovering the corner uses the ties in reverse — they start from a surviving accessory, apply the inverse bearing and distance, and arrive at the expected monument location. Corner-Plot plots every tie live on the aerial from the geolocated corner.
Monument Description and Class
The monument description block records the physical object marking the corner: brass cap on iron pipe, concrete post, chiseled square in ledge rock, aluminum cap, rebar with cap, and so on. Corner-Plot classifies these into a standard monument class (section_corner, quarter_corner, street_intersection, horizontal_control, etc.) so the geolocation engine can apply the right resolution strategy.
Stated Coordinates
Many modern CP&F forms include the surveyor's stated latitude/longitude (NAD83) and often State Plane Coordinate System (SPCS) northing and easting in feet. When present, these are the highest-confidence coordinate source. When absent, Corner-Plot falls back to multi-method geolocation: BLM CadNSDI PLSS point layers, cadastral nodes, OSM intersection geocoding, and sketch road offsets.
Surveyor Certification Block
The signature block records the licensed surveyor's name, license number, and the date of the field survey — not the filing date. The date matters: a corner record filed in 1984 predates GPS, so the ties may reference objects that no longer exist. Corner-Plot's Street View history tab lets you check the monument site across every available capture date to see what has changed.