Felling Trees Against the Lean

Illustrations by Joseph Smith

It is usually easiest to fell a tree in the direction that it’s leaning, but sometimes it’s necessary to fell it in the opposite direction. A tree leaning away from the intended direction of fall has “back lean.” By using wedges and shims to lift the trunk off the stump, you can compensate for the back lean and bring the tree up and over in the intended direction.

Once you have established the direction of fall, you can calculate the amount of back lean that must be overcome and the amount of lift necessary to do so through some simple calculations. While standing away from the tree, at a position 90 degrees to the direction of fall, sight up to the top of the tree using a weighted string or an axe as a plumb and note the location on the ground. The back lean is the distance from this point along the intended direction of fall to the apex of the planned undercut. The apex will be the front of the hinge and the pivot point for the falling stem. The weight of the tree must be brought over this pivot point before the tree will fall. In the 60-foot-tall tree at right, the back lean is three feet.

Next, figure the diameter of the stump by measuring from the front of the hinge to the back edge of the tree (see illustration). The stump diameter is used to determine the number of segments in the tree; one segment is a section of the tree with a height equal to the stump diameter. Thus, the 60-foot-tall tree with an 18-inch stump diameter has 40 segments (720 inches divided by 18 inches equals 40).

If you raise the back edge of the lowest segment one inch, you will move its front edge one inch forward. At the same time, the top of our 40-segment tree will move forward 40 inches, enough to overcome its 3-foot back lean. If the same tree had a back lean of 4 feet, it would require 1 ¼ inches of lift (48 inches divided by 40 sections = 1.2 inches) to overcome the lean. When calculating the lift, be sure to add in the 3/8-inch saw kerf, which means that one inch of lift will require 1 3/8 inches of wedge.

A combination of wedges and shims can be used to give you more lift. Cut discs of ½-inch to an inch in thickness from hardwood branches for the shims. Do not taper the discs, as that will make them weak and liable to break in the notch. Using two wedges, side by side, drive one home so that there is a gap between the stem and the top of the other wedge. Place a shim in the gap above the free wedge until it is snug, and then pound in the shim by driving the wedge. This should either fell the tree or free up the other wedge for a thicker shim. Repeat this process with increasingly larger shims until the tree comes up over the pivot point, and then gravity will take care of the rest.

Tricks of the Trade is provided courtesy of the Forest and Wood Products Institute at Mount Wachusett Community College in Gardner, Massachusetts. Information for this article comes from the Game of Logging training program.

  1. Stephen F Margiotta
    Aug 11, 2009

    I understand the idea of a wedge and shim, however, the trees I am taking down are only between,7”-9” in diameter, some are back leaning and seem too small to use a wedge, as soon as I attempt to back cut my saw jambs & I cannot cut deep enough to apply any kind of wedge?

    I’m a bit frustrated. My trees are close together which poses another problem altogether. Do I need to use a come-along to apply pressure in the direction of my fell?


  2. Keith
    Jun 29, 2010

    For a small tree, cut the back cut first, drive in a wedge lightly, and then cut the under cut.  Finish felling the tree with wedges.

  3. Jeff
    Jun 27, 2011

    Does the weight / size affect this ?
    A 3ft lean, but a 40” diameter 50 ft (a lot of weight), would there be enough strength for one to move this weight with wedges ?

  4. Mike Allen
    Sep 05, 2011

    I hung one up today; it doesn’t happen often, but it does happen.  The tree was leaning in an opposite way I intended for it to fall and landed against another tree in the wrong direction.  Headed back tomorrow up Griffin Creek with a come-along to encourage it to fall without killing me.  If it was a buckskin larch it would be an anticipated trip rather than an obligation.  However, since it is a lesser tree, it’s an obligation to just get it down.  If it doesn’t kick out and kill me, I’ll be in touch.

  5. dave
    Sep 09, 2011

    You there, Mike? Should we contact next of kin?

  6. Alan
    Mar 17, 2012

    The 1/4 cut technique is a good way of wedging small diameter trees.

  7. Bob Young
    Oct 22, 2013

    The best way how to cut a tree which leans different direction than you need it to fall down is to have a helper. Number one, you should always have safety gear like a hard head, safety glasses and gloves. Take a rope (make sure it is much longer than your tree) and either climb it or install a little log and the end of it. Throw it around stronger limb, make a knot (slippery eight loop) http://www.netknots.com/rope_knots/slippery-eight-loop. Make it tight and hook it up behind truck or atv. You can also use a few guys to pull.
    It depends how big the leaning tree is. It if is bigger tree, please don’t risk anything and call your local tree guys. It is not worthy to save $1000-$2000 to risk your life.

    Anyway, when your rope is tied and person in the truck or the atv ready, you can start cutting. Cut 70% notch into the tree with the length of 80% of the trunk’s diameter. Cut down slide first and then make upward cut to complete the notch. Make sure that your guy at the truck or atv start pulling little bit more. Then make the back cut toward to the corner of the face notch. While you cutting make sure your helpers pulling the rope more and more. This job needs to be done precisely. Your tree should start moving towards to your helpers, if you need to, cut little bit more and then escape the area by going on the left or right.
    Bob - Eastern Tree Service in Birmingham, Alabama

  8. Cornelis
    Sep 07, 2014

    What about if the leaning tree is likely hollow? We want to drop it against the lean. The tree is a 20 meter tall lombardia poplar, the amount of cutting front and back is obviously more critical. We do have a tractor 4wd 80hp and steel cable available.

  9. Diane Spence
    Mar 02, 2015

    We have a tree that the wind storm brought half way down. It has fallen onto another tree and both trees are bent over badly from heavy snow. We have cut down trees our whole life but not sure about these. Now you know my husband won’t ask…but I have no problem getting some sound advice. This site seems to me to be professional and trust worthy. Anyone with the best answer? Would appreciate any suggestions besides paying someone else…ain’t gonna happen!

  10. Dave
    Mar 02, 2015

    It’s impossible to give good advice, Diane, without seeing the trees in person. They’re going to have all kinds of funky tension on them, and what you’re describing is a dangerous situation for a tree feller.

  11. Thom
    Jun 26, 2015

    I’ve a problem complicated by another problem.

    1. I’ve 2 Spruce with trunk diameters of about 14+ inches. One was blown into, and prevented from falling by, the second such that one tree which is not cut is fully leaning into the second engaging at the tops at about 35% of the tops. The leaning tree is somewhat unrooted but not too badly.

    2. The direction it/they really have to fall involves a banking of about 10’ in height about 15’ from their bases.

    My concern is that if I cut the leaner ... it will not fall but more heavily lean into the other and be even more of a problem. If I cut the non-leaner I am concerned that the tension created by the leaner will cause a very erratic response in terms of when and how it falls. If either are cut, when they hit that banking they may easily kick back and there’s not a whole lot of places that would be safe.

    Any ideas?

  12. Jim Dominic
    Mar 25, 2017

    Just felled a 16” diameter back-leaning tree—lean was about 4 feet. Made the back cut first and inserted two 8” wedges on either side of the back cut, banged them in a bit to set them, then made the face cut. After that, I worked on banging the wedges in, alternating each side. Had to double up on one side by placing another wedge. Once the lean was overcome—and the tree was letting me know about the progress here and there—it went over in the direction of the face cut as planned.

  13. Carl
    Mar 30, 2017

    Tx for comments above. Have a 70’ high oak 16” dia slight crown above the 40 ’ mark, like the tree above Lean is a few ft South, the crown is leaning SoEast. I want to fell it East. It’s a side lean..Any special tips on the side lean and how thick to keep the hinge. Was going to use a 4ton and 1ton come along with 5 tons ropes to guide, attaching them to small trees. Any thoughts on that?

  14. Jane Genuine
    Jul 23, 2018

    Those tips are valuable but why would we want to cut a tree when it has a lot of benefits like shade and it lessens the pollution in the air? Instead of cutting it, I would suggest to keep, put a swing on it and enjoy an afternoon in your backyard with your kids.

  15. Joe Fake
    Sep 28, 2018


    Many reasons.

    1.  Wood burns and keeps our house warm.  It is a renewable power source that when replanted can resequester carbon.
    2.  The tree is dead and at risk of falling on someone or something like my house.  I suppose I could wait for it to fall so you can help pay for my new roof through your insurance premiums, but I’m not that sleazy.
    3.  The tree has partly fallen down but not completely with the same risks as number 2.
    4.  To pretend we are Paul Bunyan.  It is fun to do.  Everyone should have the experience of felling a tree at least once in their life.  My girls will.
    5.  Some trees are junk trees with little to no benefit for certain animal/plant habitats that are being encouraged.  Removing specific trees can help open the canopy.
    6.  To remove invasive species.
    7.  To clear land for improvements (house, driveway, garden, pool, etc.)
    8.  To harvest trees for wood products/lumber.  Search for Alaskan Chainsaw Mill.  Anyone can do it.  Or hire someone with a portable mill.
    9.  Because some people prefer the look of a manicured park to wild growth forest.
    10.  Because not every tree provides shade or is adequate for hanging a swing.  Plus if I put up a swing on every tree I owned - it would be swing pollution.  (Hint I have 5 acres of trees.)

    These were just 10 quick reasons off the top of my head.  Please actually think before you post.  I have never met anyone who doesn’t love trees.  But there are valid reasons to remove them just like there are valid reasons to use electricity from coal, nuclear, wind, and water power.  That is unless you want to live in the Stone Age without fire in a mud hut.  But then again, maybe you live somewhere warm year round.

    But anything can be taken to an extreme or done wrong.  I’m just grateful there are sites like this to help keep people safe.

  16. Elise
    Nov 18, 2018

    Uncertain if backlean would work for me. High winds past several years have shifted lots of trees on the front face of windbreak. Most roots have been pulled out. Tree, roots and all…...no disease.

    These trees are leaning on other small trees. About 15% angle.

    Neighbor said just cut pulled-out roots. I don’t think that will work.

    Would love to see illustration how to cut.

    Much deep thanks!

  17. My2centz
    Dec 20, 2018

    I have a dead tree about 80’ tall and I’d say around 10” to 12” at the base. It goes up about 25’ then it starts bowing out about 6’ then back to the top leaning over my driveway. It’s not gonna hit anything except maybe another tree when it falls but I’d guess it’s so dead it will probably just break which also poses a problem but I’m sure I’ll be out of the way. It does look like it wants to fall where I want it to however this thing is Dead Dead Dead and I’ve never cut down a tree this dead. I’m afraid that when I start cutting it will just snap and I can’t find any good examples online to assist me with this. Any ideas of how I can do this safely and the risks I face attempting this would be helpful. If it does hit a tree it would be about 80% of the way up and it has no branches on it at all its so dead.

  18. Dave
    Dec 24, 2018

    What you’re describing seems high risk to me.  You’re right that a tree that dead could snap, and it’s hard to say where it would snap.

  19. Alan Fligg
    Dec 25, 2018

    Trees bring us closer to God without the burden of religion and its guilt. Harvesting trees and wildlife is God’s way,  if done with respect and intelligence.Without both, nature can become deadly.

  20. mickey miller
    Feb 10, 2019

    I have a 45’ tree that leans “almost ” correctly.  If I cut it the way it leans the top 15’ will hit the fence. I need it to land 3’ farther to the right . Should I make a partial back cut and put a wedge in the left side then finish the cut to make it fall to the right?

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