A systems approach to climbing and safety
As with all complex tasks, production tree climbing is a series of processes, actions and forethought. A useful way to combine the physical and mental challenges of modern tree climbing with the proper skills and tools is to use a systems approach. Addressing the task of accessing, ascending and working a tree as a series of systems allows the climber to stay focused, consistent and efficient. When safety, as a core value, is integrated into a systems approach, the climber adds health, professional longevity and proficiency to the job.
The military’s credo “routine things in a routine manner” applies to production climbing as well. When climbers turn their daily tasks into routine, details are incorporated, and attention to details can be the difference between a job that is profitable and one that is not. Details can also be the difference between finishing a climb safely or ending your day injured.
Here are four steps climbers deal with daily. The processes, procedures and decisions made throughout these steps form a holistic system for safe, efficient, productive tree work.
Step 1: pre-climb inspection
An absolutely vital step before any climbing task can begin, and the first component of our system, is the pre-climb inspection. In this inspection you are looking for red flag indicators, which can be anything that may cause you to question the safety or stability of the tree and/or interfere with the ability to complete the task safely. Storm-damaged limbs, cracks, cavities, insect/animal nests and fruiting bodies on or around any part of the tree are just a few examples of possible red flag indicators.
Start with an outer perimeter survey, which consists of a 360-degree trip around the tree from beyond the drip line. Begin away from the tree to avoid any potential hazards.
The outer perimeter survey is followed by an inner perimeter one. After establishing that the main canopy is safe to go under, take a closer 360-degree survey of the tree, and look at the trunk and main scaffold limbs for red flag indicators. During the inner perimeter survey, closely check the static relevant zone, which is the area directly around the trunk, root collar and rootzone extending about 5 feet (1.5 meters) out from the tree. This area is most likely to show evidence of major structural flaws as the tree bends and moves. On a windy day, this zone is easy to inspect as the tree is already moving. If there is no wind, use a throw line and the assistance of a co-worker to get the tree to sway gently. Check for cracks or cavities that may be opening and closing as the tree sways, and feel the ground for heaving of the root plate. Also, use a plastic or rubber mallet to sound the tree for hollows or inconsistencies. As the tree sways, step back and observe its motion. It should move naturally and generally according to what is around it. Experience and an in-depth knowledge of the species, its habits and forms will help with this process.
It is important to remember that while you climb and work, the inspection process must never stop. You must continue to assess the tree for red flag indicators, and while in the tree, a closer inspection is possible and unseen hazards may be found. Furthermore, as you work in a tree, especially during a removal, you change the structure of the tree, and this may introduce new and different forces on an established structure. Become aware of these new forces and change your plan as needed.
Step 2: pre-climb plan
Once you have determined that the tree is safe to climb and work, it is time to plan your climb. A work plan incorporates the work to be completed (pruning, removal, etc.), the hazards and obstacles to be mitigated or avoided, the tools available and the skills of the climber. Not only must the climber ascertain what work is to be completed, they must further isolate it to sections of the tree. For example, a woods-grown tree near the edge of a field may have an asymmetrical crown, and therefore more pruning on one side will be necessary. The climbing plan should reflect this.
Determine a tie-in-point (TIP). Ideally, a TIP is high and centrally located over the work area. However, this is not always possible, and multiple TIP’s or redirects may be necessary and included in the plan. The TIP should be of suitable size for the tree species and inspected closely for integrity. Incorporating the main stem into the TIP as opposed to just using a single branch, is preferable.
Achieving the perfect TIP from the ground is not always possible, or desirable. Let your skills, the situation and your initial plan guide you. The ability to advance up the tree and not have to reconfigure a TIP is indeed a time-saver. However, high TIPs are difficult to inspect and tend to make the climber not assess the tree thoroughly when ascending (once the final TIP is established, a climber tends to concentrate on completing work) and may take too long. Two or three missed throws at the perfect TIP suffice, then alter the plan to hit a lower TIP and climb the tree.
Step 3: entering the tree
After determining a probable TIP, the climber needs to ascertain how to advance to that TIP. Often, a throw line is used, but other methods from single line techniques (SLT) to simple lanyard advance are possible. Many techniques exist for entering a tree. The venerable doubled rope advancing technique is still as viable as an advanced SLT. Each tree, climber, job and situation is different.
Climbers need a thorough understanding of the forces involved as well as the advantages and limitations of each system employed. A professional, experienced climber is familiar with a number of ascent climbing systems, but more importantly, knows when they are not appropriate.
Step 4: working safely aloft
Working in a tree requires a combination of tools: the climbing line, the suspension harness, the choice of knot or friction management device, and the personal lanyard all combine to form the work positioning system. As with all systems, the variations are numerous.
Saddles or climbing harnesses come in two separate categories: leg strap and butt strap. In leg strap saddles, separate straps hold each leg independently. This gives the climber greater mobility while in a tree, but can be uncomfortable to sit in for long periods of time. Butt strap saddles incorporate a single strap that the climber sits in, and on some models, this seat is rigid. This type is more comfortable to sit in, but is somewhat more restrictive of leg movement.
Climbing hitches fall into two general categories: open and closed. Open hitches have a tail that exits the knot and needs to be secured with a stopper knot. They are typically tied using the end of the climbing line, and can be tied with a separate piece of cordage termed a split tail. An example of an open system knot is the tautline hitch. Closed system knots incorporate both ends of the friction hitch cordage in the knot itself. Because of this, they are inherently more secure from rolling out during a climb. However, a separate piece of cordage must be used and the knot typically rides closer to the climber, making some techniques, such as body thrusting, more difficult without ground assistance. An example of a closed system knot is the distal hitch.
Many reputable companies make high-quality types of arborist climbing lines. Modern climbing lines incorporate the advantages of lighter weight and firmness with a good hand or feel and “knotability,” the ability to consistently hold knots without excessive tightening. Diameters are a matter of preference. A line that stays rounder under tension will work better with a wider variety of hitch cordages and knots. A stiff rope works better with mechanical devices, but may lack knotability.
Personal protective lanyards come in many shapes and forms. Again, the specific type is a matter of preference. A good lanyard system should match the climber’s climbing style and general climbing conditions. If a great deal of work is done on single-stem trees with little crown spread, then a shorter, more basic lanyard may suffice. If work conditions often find a climber in wide, spreading trees where access to the outer part of the canopy is necessary, then a longer lanyard that mirrors a climbing system may be the answer.
By breaking the climbing process down into four general steps, a system is developed in which a climber can construct their daily routine. First, establish a protocol for pre-climb inspections. These should not be ignored for the more glamorous aspects of production climbing. Climbing equipment and skills can be top-notch, but will do no good if the tree fails underneath the climber.
Next, develop a work plan that coincides with a climber’s skills and equipment, general work types, conditions and expectations. Aligning these takes time, patience and perseverance. From a safety and productivity standpoint, there are no right or wrong ways, only safe and unsafe. If you prudently, proficiently and effectively fulfill your job and equipment requirements with planning, skills and tools, you will discover a plethora of ways to complete each and every task safely.
Enter the tree with an efficient and appropriate method. A thorough understanding of the forces involved and the advantages of various systems are crucial. Finally, work the tree according to your plan with a mind to change as needed.
Looking at tree climbing through a systems approach, or a series of tasks to be completed step by step, helps the climber achieve the goal of having the proper equipment and skills to safely complete any tree while attending to the details.
Tony Tresselt, a writer, ISA certified arborist, TCIA certified tree care safety professional and instructor for North American Training Solutions, works for Arborist Enterprises in Lancaster, Pa.