What is the 5-15-90 rule?

If you’ve ever watched somebody drop a tree and thought, “That looked easy,” I can promise you—it wasn’t. Tree felling done right is controlled chaos. And one of the simplest ways pros explain that kind of precision is with the 5-15-90 rule.

This isn’t a gimmick or a catchy phrase. It’s about discipline, physics, and respect for gravity. Because when you’re working around homes, driveways, power lines, and fences—the typical Minnesota backyard—tiny errors can turn into expensive problems fast. The 5-15-90 rule keeps that from happening.

Let’s break it down.

Statement Tree Services

The 90%: Planning Is Everything

Ninety percent of a successful tree removal happens before the saw even starts.

This is where pros earn their keep. We’re evaluating every variable:

  • Which way the tree naturally leans (and where the heavy side is)

  • Wind direction and speed

  • Dead or cracked limbs

  • Condition of the hinge wood

  • Escape routes

  • Overhead hazards like power lines

  • What’s nearby—houses, fences, sheds, decks

Every tree tells its own story. You can read it in the bark, the trunk, and the grain. Skip that—and the tree will write the ending for you. And gravity? It always wins.

Before a pro ever makes a cut, they’ve cleared two escape paths at 45° angles from the fall line. When that tree commits, there’s no time to think—you move on instinct.

The 5%: The Face Cut

Five percent of the job is cutting the notch, and that little cut controls everything.

The face cut (or notch) goes on the side of the tree in the direction you want it to fall. It creates an opening that “tells” the tree which way to go. Usually, that’s a 70-degree opening, about 20–25% into the trunk.

Too shallow, and you lose control.
Too deep, and you lose strength.
Wrong angle, and the tree twists mid-fall.

That 5% is surgical—it sets the whole production in motion.

The 15%: The Back Cut & Hinge

The final 15% is the back cut, where precision and danger meet.

The back cut is made on the opposite side of the notch. Between the two cuts, you leave a strip of wood called the hinge. That hinge is what steers the tree on the way down.

Make it too thin, and the tree can snap or go off course.
Make it too thick, and it can split or sit back on the saw (a “barber chair” — one of the most dangerous situations in tree work).
Cut it at the wrong height, and you lose leverage.

The hinge should be about 10% of the trunk’s diameter. Get it right, and the tree folds smoothly into the notch, landing exactly where you planned.

Why It Matters Here in Minnesota

We’re not felling trees in open forests—we’re doing it between houses in Edina, near lakes in Minnetonka, and on narrow lots in Maple Grove. There’s no margin for error.

The 5-15-90 rule keeps every part of the process disciplined:

  • Plan completely (90%)

  • Cut with intent (5%)

  • Execute with precision (15%)

And if a tree can’t be safely felled using those steps—because of rot, lean, or limited space—we don’t gamble. We switch to a lift, use rigging, or dismantle it into pieces. Controlled removal always beats a risky fall.

Tree felling isn’t about brute strength. It’s about physics, geometry, and patience.

When it’s done right, it looks effortless.
When it’s done wrong, it’s a disaster.

Around here, we never gamble with gravity.