Principal Structural​/Civil Engineer

Pincushion Corners:
How They Happen — and How Mentorship Can Stop Them   Introduction   If you've ever dug around a corner monument and found three, four, or even ten separate pins all within a couple of feet of each other, congratulations—you've encountered one of the land surveying profession's most persistent and damaging phenomena: the pincushion corner.
It’s one of the most visible signs of disunity in our field. Not only does it confuse property owners, courts, and future s...urveyors—it directly undermines public confidence in what we do. And yet, it keeps happening, decade after decade, across urban subdivisions, rural metes-and-bounds, and everywhere in between.
This article explores the why, the how, and—most importantly—how we fix it, not just through better tools or tighter rules, but through mentorship and professional growth.
A pincushion corner is the result of multiple surveyors, over time, setting their own physical corner monuments—iron rods, pipes, caps, etc.—in the same general location, but not in agreement with one another.
You’ll find one pin set in the 1970s, another in the 90s, maybe two more from the 2000s, and a fresh one from last week—all within a foot or two of each other. Each surveyor likely believed they had the “right” spot.
But only one of those pins—if any—accurately reflects the true boundary corner based on the legal, historical, and physical evidence available.

The Damage It Does Breeds distrust — Courts, attorneys, and the public begin to see surveying as arbitrary.

Increases costs — Future retracements become more difficult and expensive.

Erodes the profession — When we don’t agree on corners, we lose our authority as boundary experts.

How Pincushion Corners Happen   To fix the problem, we must understand its causes. Pin cushioning is not random—it’s rooted in psychology, training gaps, poor habits, and systemic issues within the profession.
Let’s examine the most common causes.
1. Ego and Overconfidence   Some surveyors—especially those early in their career or those who've never had a strong mentor—develop an over-reliance on their own calculations.“This doesn’t fit my math, so it must be wrong.”They might disregard existing evidence because their CAD drawing or GPS shot says otherwise. This mindset overlooks a key truth: you are not the first person to survey this land, and your job is to retrace, not redesign.
2. Fear of Liability   Another common reason surveyors set new corners is fear. Fear of being wrong. Fear of accepting a prior monument that might not be “perfect.” So they default to what feels safe: setting their own corner and disclaiming the old one.“If I hold this old rebar and it's off by 0.5’, I might get sued. Better to set a new one and say it’s mine.”But

this is legally backwards. If a prior monument is defensible—supported by record evidence, longstanding occupation, or historical consistency—holding it is often the most defensible thing you can do.
3. Lack of Historical Understanding   Too many surveyors rely solely on coordinates, record plats, or modern deed calls, without digging into the historical context that shaped the property in the first place.
They might have no idea that the original survey was run with a chain and compass, or that the local custom was to measure from a centerline, not a lot line. So they treat the deed like gospel and ignore reality on the ground.
This is especially common in places like:

Rural Appalachia, where deed descriptions might start with “from the big rock near the creek…”New England towns, where 200-year-old stone walls are better evidence than any rebar.

Without a mentor, it's easy for new surveyors to miss these nuances.
4. Production Pressure   Some survey firms prioritize speed over precision. You’ve got 8 boundary surveys due this week. Your boss wants them fast. So you use the record data, do a quick traverse, and drop a new corner without full recovery.“I’ve got no time to chase down an old fence corner or dig for buried iron—just set the pin where it math-checks and go.”This

isn’t surveying. It’s corner-littering. And it’s one of the biggest contributors to pin cushioning in subdivision work,…