We finally arranged for our tree guy, Jerry, to come by with one of his helpers to remove the two maples that shade our garden in the late afternoon (see February 6, 2013).  We had meant to get this done before the trees sprouted their leaves (it would have made less of a mess) but didn’t get around to it.  Now that the garden is in full swing, though, we need the extra solar exposure.

When Jerry removes a tree near the house, he follows a very careful and elaborate procedure.  First, he cuts off the outer branches, then he tops the tree, and brings the trunk down section by section.  Sometimes, as a final step, he removes the stump by grinding.  The stump-grinding equipment is truck-mounted so accessibility is an issue; consequently, we have several stumps on our property.

Jerry chips all but the largest branches and takes the rest away.  When we have needed firewood, he has cut the trunk into appropriate lengths and left it for me to split and stack (see, for example, February 5, 2012).  Tree removal is a very labor-intensive activity but when Jerry and his crew are done, the only signs of their having been there are tire tracks and a scattering of sawdust.

The same approach would not be practical for today’s project.  The trees in question are just outside the border between our pool area and the surrounding woods, a transitional zone between order and chaos.  They are over 100 feet from the road and their bases are on a steep slope.  The trees could be cut down in the same way but removing the branches and wood would require an unjustifiable amount of effort.

So instead, we will leave the downed trees in place.  And if we are going to do that, there is no reason to cut them into pieces.  Bringing them down in one fell swoop (each, for a total of two fell swoops) is more appropriate.  (I had hypothesized that felling trees was the literal origin of the saying, “one fell swoop,” but my research revealed otherwise.  Fell can mean cruel or fierce while swoop in this context refers to the sudden dive of a bird of prey.  Given the sound a tree makes when it is felled, I like my story better.)

Felling a tree with a single cut at the base is much more difficult than it might at first seem, especially if the direction in which the tree will fall is of concern.  In fact, it can’t be done reliably with only one cut.  If the saw is not properly aligned with the direction the tree wants to fall (due to the location of its center of gravity), the weight of the tree will close the kerf as the tree starts to lean and that will bind the blade.  Unfortunately, I have to admit that I know this from firsthand experience.

Most often, three cuts are needed.  The first two cuts are made on the fall side of the tree to remove a wedge of the trunk.  This forms a hinge about which the falling tree will rotate.  The third cut is made on the side opposite the wedge and if all of the cuts have been done properly, the tree will start to fall due to gravity before the final cut makes it all the way through the trunk.

Geometry cannot be ignored, however, and even if the cuts are made correctly, the tree still might want to fall in another direction.  Based on Jerry’s assessment, this is the case with our trees, both of which are leaning slightly uphill, towards the pool.  Obviously, this is not the direction we want the trees to fall.  To counteract the trees’ gravitational tendencies, Jerry attached a rope near the top of each one to pull them in the direction he wanted them to fall.

Getting the ropes into the trees took a certain amount of finesse.  For the first tree, Jerry knotted the rope to a length of lightweight line—string, almost—at the end of which was a small beanbag slightly bigger than a Hacky Sack.  He carefully launched the beanbag up and into the tree with an underhand motion, aiming for a branch high on the trunk.  It took two tries but the second toss sailed through the crotch and dropped back to the ground.

Using the lightweight line, Jerry hoisted the main rope up to the top of the tree and back down.  Then, he formed a loop (tree work requires as much knotting skill as sailing, it appears) and cinched the rope around the tree trunk.  His helper took the free end downhill (the direction we want the tree to fall) until the rope formed about a 45-degree angle with the horizontal.  There, he anchored the rope to another tree trunk.

Using an in-line winch called a come-along, the helper took out the slack in the rope and then applied some tension.  At this point, Jerry starting cutting the notch on the fall side of the tree.  After confirming that the rope was taut enough to prevent the tree from shifting in the uphill direction, he completed the notch.

Then, the dramatic part began.  The helper continued to winch up the rope while Jerry commenced the final cut.  As the helper cranked up the tension, we could hear the tree trunk creaking and see it starting to list downhill.  When the tree was leaning by about 15 degrees from the vertical, there was a loud crack as the trunk gave way.  Both Jerry and his helper moved back and with a loud thwump, the tree fell to the ground, precisely where Jerry had intended it.  Quite a spectacle!

The second tree had several branches extending almost horizontally from the trunk.  Jerry judged that these outriggers would interfere with a clean fall so he decided to cut them off.  He strapped on a lineman’s belt and climbing spikes and scrambled nimbly up the tree, pulling two ropes with him.

When he got near the top of the tree, he tied himself off with one—his safety line—and looped the other over a branch to use a belay line for the cut branches.  I have described this process before (see October 31, 2011) and it is particularly elegant when Jerry rappels between locations, his chainsaw and pruning blade dangling from his belt.

After trimming and dropping the protruding branches, Jerry returned to earth.  He freed himself from his safety line, knotted a loop in it and cinched it up to use as the tension rope.  His helper again marched the end of the rope downhill and, following the same procedure as before, he and Jerry brought down the second tree, felling it almost exactly parallel to and on top of the first tree.

Described this way, it seems like it would take a long time to perform all of these steps.  But after only an hour and a half, Jerry and his helper were packing their gear up and heading to their next project.

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