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12 Arbor Age / September 2014 www.arborage.com TRAINING & EDUCATION TRAINING & EDUCATION enough. Care should be taken to select the proper diameter of spider leg, typically 1/8 inch smaller than the rigging line being used (1/2-inch rigging line = 3/8-inch spider leg), as this will create the required "grip" in the hitch while not "gripping" too much as would a signifi cantly smaller diameter spider leg. Location, location, location As in all things, location is very important in lifting, but particularly important is the location of the anchor point relative to the piece being lifted. The type of lift being car- ried out is going to dictate the location of the anchor point; and, as always in tree care, the structure and the strength of the tree itself. The use of some type of block or pul- ley is required in lifting operations, for although it may be possible to lift a branch or piece through a natural crotch, the friction involved is going to be extremely hard on the tree and rope involved and require much more energy/force to lift. A branch that is being balanced is going to require an anchor point that is almost directly over it and centered over the load to avoid any swing or lateral movement. If a swing or lateral movement is not a problem, then the anchor point can be off to the side; but the use of some form of control line to lessen the swing is recommended. And, of course, all personnel involved need to be prepared for the branch's movement after sepa- ration. A scenario that is going to take a horizontal branch/piece and lift it to vertical prior to separation requires an anchor point as much directly over the intended cut as possible. In this scenario, having the anchor point in a different location changes the forces/ vectors on the branch being lifted and can lead to problematic outcomes. You want me to lift what? This might be the statement made by most branch managers if instructed to provide the lifting force in a branch lifting operation; and rightfully so. The input force required in most lifting rig- ging scenarios is going to require far more than any Johnny B. O'Doughnuts is going to be able to generate. Thus, lifting operations require the use of winches, mechanical advantage systems, or Hobbs/GRCS type systems. Regard- less of which system is used, it should be set up so the operator can "hold what they got" without any slippage of the load. This is obviously no problem with a GRCS or Hobbs, but the use of mechanical advantage sys- tems or fi ddle blocks may require the thoughtful placement of a Port-a-wrap or other friction management device prior to the lifting action beginning. Additional thought and plan- ning need to go into what is going to happen to the piece once lifted. If it will simply be lowered, then the GRCS or Hobbs will neatly transition to that action, but, once again, other systems might require pre-lifting setup. If the piece is to be "drifted" or otherwise moved laterally, the system to carry out that action needs to be in place and "good to go" prior to lifting for a smooth, safe transition. A spider leg demonstrated in balancing a branch. Note the use of the hitch on the rigging line. Photo by M. Tain A site with an abundance of anchor points is always welcome in lifting operations. Photo by T. Clausen