Tying In
The choice of where to tie in is very important. Generally, it is desirable to pick a high, central location in the tree. This allows freedom of movement and easy access to most points in the tree. The higher the tie-in
figure 4.19 The higher the tie-in point, the farther the climber can move out on the limbs. It is easiest to work when tied in directly above the working area. It is very important not to tie in to a crotch that would allow a swing toward power lines in the event of a slip or fall.
point, the farther the climber can move out on the limbs. It is easiest to work when tied in directly above the working area. The more vertical the climbing line, the more secure the climber. It is very important not to tie in to a crotch that would allow a swing toward power lines in the event of a slip or fall.
figure 4.20 Choice of where to place the line is important. Choose a sturdy limb and lateral branch. Tie in around the parent limb or trunk and over the lateral limb.
The crotch selected for tying in should be wide enough for the rope to pass through easily. The size of the limbs varies with species and wood strength, but generally the main branch should be at least 4 inches in diameter. The climbing line is tied in by passing it through a crotch, around the larger limb or trunk, and over the smaller or lateral branch. This way, if the smaller branch breaks clean, the rope will simply drop to the next branch down, rather than out of the tree.
Climbers may also choose to use a false crotch when tying in. This can reduce wear on the rope and damage to the tree and can, in some cases, facilitate climbing.
The climber can tie in by first attaching the climbing line to a carabiner or snap that is attached to the D-rings of the climbing saddle. In a traditional climbing system, the climber would leave a long tail in the
figure 4.21 When tying in, the climbing line is usually attached to both front D-rings or the floating front D-ring.
figure 4.23 Innovations in climbing techniques and equipment have brought about alternative climbing systems. This drawing illustrates dual tie-in points using double-locking carabiners, a split-tail for tying in, and a micropulley fair lead to tend the friction hitch.
FIGURE 4.22 A split-tail is a separate, short length of rope used to tie the friction hitch in a climbing system.
climbing line beyond where it attaches to the rope snap or carabiner. An alternate means of tying in involves tying the end of the climbing line (or girth hitching a spliced eye) to an appropriate carabiner attached to one front D-ring. A split-tail is attached to another carabiner on a second front D-ring. The tail, either from the climbing line attachment to the saddle or the split-tail, is then used to tie a friction hitch to the other leg of the climbing line. When tying in with a tautline hitch, a Blake's hitch, or any other open-ended knot, a figure-8 knot should be tied in the tail from the climbing hitch as a stopper knot to prevent the end from going through the climbing hitch.
FIGURE 4.22 A split-tail is a separate, short length of rope used to tie the friction hitch in a climbing system.
figure 4.23 Innovations in climbing techniques and equipment have brought about alternative climbing systems. This drawing illustrates dual tie-in points using double-locking carabiners, a split-tail for tying in, and a micropulley fair lead to tend the friction hitch.
It is a good idea to use a climbing line that is long enough to allow the climber to reach the ground. If there is any question of this, the climber should tie a stopper knot in the opposite end of the climbing line when working in tall trees to prevent the end from passing through the climbing hitch if the climber reaches the end of the line when descending.
Sometimes it is helpful for a climber to double-crotch. Double-crotching is simply tying in at a second crotch, using the far end of the climbing line, or a second line in large trees. The climber can be secured against a fall while crotching the climbing line at a higher point. The lower tie-in would be untied as the worker climbs past. The double-crotching technique may also be used if the climber is ascending a second leader in a tree with a wide spread. The climbing line can be used to help climb the upright limb without sacrificing the original tie-in point. Another use of the double-crotching technique is to allow the climber to be suspended between limbs. This can be useful for installing cables, working on hazardous lower limbs, working on storm-damaged trees, or transferring from one tree to another.
There are, however, limitations with the double-crotching technique. When using the opposite end of the climbing line for the second tie-in, a loop of line is created. If this loop does not reach the ground, ground workers will be unable to use the line to send anything up to the climber. Also, unless the climbing line is long enough, the climber may not be able to descend to the ground without untying one of the tie-in points. This could present an extra difficulty in an emergency situation.
figure 4.24 Double-crotching is a good technique for working in a wide-spreading tree or to move to a second tree.
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