By Michael Tain
Although climbing arborists spend a great deal of time and energy deciding which particular ascent method is the safest and most efficient to gain access to trees’ canopies, an additional skill of equal importance is safe and efficient movement throughout the canopy once that access has been gained. The following are just a few basic introductions to various concepts that should open the way for climbing arborists to develop and refine their own unique style of moving safely and efficiently through the canopy to accomplish their work.
* Rope angle and the climber triangle: The most basic means of maintaining balance, safety and security while moving through the tree is related to the climber’s rope angle. The higher the tie-in point (TIP) is above the climber’s position — assuming a relatively clear path from the TIP to the climber — the better the rope angle. This advantageous rope angle is only beneficial to the climber if it is used correctly and appropriately by keeping his or her weight in the line as much as possible at all times. This method of leaning back into the line establishes the climber triangle with the rope, the trunk of the tree, and whatever branch or surface the climber is on — all forming the various sides. The angles involved and lengths of the sides will all obviously change as the climber moves throughout the canopy. However, keeping his or her weight in the line, assuming there is a good rope angle, will improve balance and security, particularly in comparison to attempting to balance upright while walking a limb or making a pruning cut with no support from the climbing line.
* Double tie-in: The double tie-in is intended to give the climber more support and stability by providing a second TIP. It may be used with a single climbing line, using both ends, or with two separate lines (one for each TIP). In the double tie-in’s most basic form, the climber passes the unused or running end of the climbing line over a suitable TIP and attaches it to him or herself with the addition of an appropriate climbing hitch. The climber is now effectively tied in at two separate points in the canopy, greatly improving their support and balance. Climbers using this method must be aware of the loop of the standing part of the line beneath them and realize that they will only be able to descend so far before running out of rope, as they are using both ends of the line. An additional disadvantage with this method is the necessity of tying and manipulating two climbing hitches with the attendant number of connections to the harness. An advanced refinement of this method has been developed and popularized by Mark Chisholm in which the climber passes the working end of the line through a carabiner or pulley for smoother movement, secured at a center attachment point of their harness. The working end is then passed over a second suitable TIP and reattached to the harness. The climber is now supported by two TIPs, but is only using one climbing hitch and only has one end of the line attached to the harness, simplifying the method quite elegantly. Once again, climbers using this method must be aware of the possibility of running out of line if they need to descend too far with this system, as they are using roughly twice as much rope.
* Natural and manufactured redirects: Often when attempting to work far out at the end of a limb or in a particularly awkward spot in the canopy, climbers will be confronted with the possibility of a dangerous swing even when they have an excellent rope angle. This exposure can be reduced or even eliminated through the use of natural or manufactured redirects. A natural redirect is simply descending down through a branch union or over a horizontal branch above the desired work location. The branch union or branch then redirects the climbing line, preventing exposure to a dangerous swing back toward the trunk in the case of loss of balance or uncontrolled movement. Manufactured redirects take many shapes and forms, but are primarily the use of webbing, carabiners, pulleys and a variety of other gear to create either a redirect where no branch union exists, or to create a redirect with less friction than the natural redirect might produce. The intention, as with natural redirects, is to prevent exposure to a dangerous swing, or, in some cases, improve a poor rope angle. Manufactured redirects should meet the standards required for personal support even though they are not the climber’s primary means of support. This is for the simple reason that in the event of a failure, the climber will be exposed to exactly the dangerous uncontrolled movement they were trying to avoid by using the redirect.
* Fairlead: The use of a fairlead pulley beneath the climbing hitch, though quite simple and basic, provides large benefits during canopy movement. The pulley directs the climbing line into the hitch in a straight unobstructed manner, or leads the climbing line into the hitch fairly, thus preventing the necessity of “tailing” or dragging slack climbing line over or around a branch or trunk to help the hitch function smoothly.
Moving through the canopy is how climbing arborists take care of the needs of individual trees or accomplish tasks specific to various jobs aloft. The development of a safe efficient personal style of canopy movement is a task that all climbers are continually refining and expanding in order to finish work more quickly and safely. The basic methods, techniques and tools discussed here will hopefully help climbers in that development and refinement of their personal style.
Michael “House” Tain is a contract climber, splicer, educator and writer currently located in Lancaster, Ky. He can be reached via e-mail at firstname.lastname@example.org