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Communication As always, good communication is key on any tree job, and the demands of rigging make it even more vital. All crew members should be familiar with whatever system the crew employs; and be extremely watchful of what is going on within the rigging plan.The rigging plan should be discussed beforehand with all crew members,with everyone knowing what is supposed to happen when,and what their role is in it. In addition,the noisy environment may require alternative communica- tion methods such as hand/arm signals,whistles,radios,etc.;and everyone should be familiar with how they will be used and employed. Knotless rigging This term is for rigging systems that try to minimize or eliminate the use of knots or hitches to attach pieces to the rigging line as much as possible.As a system,its greatest advantage is the speed with which pieces can be attached and detached from the system;and there may be a slight increase in overall rope strength by eliminating knots within the system. A knotless system can, as can all the techniques discussed here, also be used in conjunction with others such as drift or slide lines.A large eye spliced in the working end of the rigging line is one of the simplest meth- ods to eliminate the need for a knot, as the large eye can then be girth hitched around the pieces to be rigged.An additional knotless rigging method is to splice a smaller eye in the end of the rigging line with some form of connecting link in it — typically a captured eye ladder hook or steel rigging carabiner.This connecting link can then be attached to slings girth hitched around the piece;and even multiple pieces if lighter loads are being rigged.Although this method is certainly acceptable and handy if used correctly, care should be taken not to side or cross load the con- necting link or hook it back to the rigging line itself.This can result in poor loading and bending radii that are quite unfavorable to rope strength. Balancing Balancing limbs in their original orientation is a technique that can be very useful over obstacles,but extremely difficult,if not impossible, to achieve by trying to guess the exact middle of the limb or piece, and attaching the working end of the rigging line there.A much better,and more successful option,is the use of spider legs or balancers —anywhere from one to as many as are required — to create a "cradle" of lines that support the piece.The unspliced ends of the spider legs or balancers are attached to the piece,and a Prusik or other suitable hitch formed around the rigging line with the large eye spliced in the other end of the spider. This provides an adjustable "rope grab, "which the climber can move up and down the rigging line to achieve near-perfect balance prior to the limb even being cut.This technique,within reason of course,can also be used in combination with the others discussed here. Lifting Almost as valuable as balancing a limb or piece is the ability to lift it into a vertical position under control, to then be lowered to the ground or attached to one of the other advanced systems discussed here for further movement.In order to minimize violent swings, the anchor point for a lift should be as near as possible to directly above the proposed "cutting point" as possible; and the cut itself is fairly technical in nature.In short, the climber must view the limb as a tree to be "felled"upward, with a www.arborage.com A five-to-one mechanical advantage system that could be used to provide the "pull" for a drift line, lift a limb, or tighten a slide line. Photo by Michael "House" Tain A spider leg balancer and rigging line used to keep a branch in its original position after being detached. Photo by Michael "House" Tain face notch on the upper surface of the branch,and a back cut below. In addition,the notch should be wide enough that the hinge will not break prior to the branch becoming vertical, once again to prevent violent movements.A general orientation would be one cut of the face notch should be perpendicular to the branch, with the other parallel to the ground,but the cut will typically be quite specific to each branch to be lifted. Lifting the branch will require the use of a GRCS or mechanical advantage system,thus adding complexity,but the technique can be quite useful in very specific situations. Load and drift The use of secondary lines to "drift"a piece one way or the other to a desired landing zone can be quite advantageous.Not only does a drift line produce the desired controlled movement and,used correctly,pre- Arbor Age / October 2012 9