Up, Down, and Everything In Between: A Guide to Ascending and Descending Tools

Moving efficiently through the canopy is the heart of tree climbing. Whether you're a recreational climber heading up for the view or a professional arborist tackling a complex removal, the tools that get you up and bring you down safely are among the most important investments you'll make. Understanding the options—from traditional knots to modern mechanical devices—helps climbers build a system that matches their skill level and climbing style.

Every climber starts with the basics. The traditional climbing method uses a rope hung over a branch, tied into a loop, and connected to the harness. Ascending and descending happens by using friction knots to shorten or lengthen the rope loop. This system, formerly called doubled-rope technique (DbRT), is now known as the moving rope system (MRS)—the only climbing system in the world where the rope moves over an anchor point.

But as climbers gain experience, many look for ways to make the journey up and down the rope easier, faster, or more ergonomic. That's where mechanical devices come in. Some are designed for ascending only, some for descending only, and others—the most versatile—handle both directions.

Ascending Tools: Climbing Smarter, Not Harder

Mechanical ascenders attach to the rope, a foot, or both feet to assist with upward movement. While they can make climbing significantly easier, there's an important rule: these tools should only be used after a climber has mastered the traditional knots-on-rope system, such as the Blake's hitch.

Hand Ascenders were once the standard for mechanical ascent. These devices feature a handle and a hinged cam with teeth that grip the rope when loaded. The teeth come in two styles: straight teeth are considerably kinder to the rope, while angled teeth can mangle the rope if a climber falls. Interestingly, most modern climbers have moved away from hand ascenders, preferring combination devices that handle both ascent and descent in a single tool.

Foot Ascenders are a game-changer for efficiency. By transferring the work to the leg muscles—which are far stronger than arm muscles—foot ascenders make climbing less strenuous and more ergonomic. They can be purchased for the right or left foot, though some models are ambidextrous. The critical safety note: a foot ascender is a climbing aid, not a life-support device. The climber must always be tied in with a separate life-supporting attachment. And perhaps most importantly, the foot ascender must be removed before descending, or the climber will find themselves hanging upside down in a complicated situation. Practicing the removal process near the ground before a climb is a smart habit to develop.

Knee Ascenders work in tandem with foot ascenders to create a "rope-walker" system. This setup uses a floating ascender and a bungee cord to give the climber a stair-like walking motion up the rope. It's a remarkably efficient technique that can be used with either a moving rope system (MRS) or a stationary rope system (SRS). As with any new system, the advice is simple: start slow, go low, and grow.

Descending Devices: Control Is Everything

Descending devices have their place, but they are fast becoming outdated as newer systems are developed that handle both ascent and descent. However, understanding them remains important, especially for their safety limitations.

The classic figure 8 is a simple and inexpensive descender, but it has a critical flaw: if the climber lets go of the rope, they drop to the ground. The same is true for a rack descender. These devices rely entirely on the climber maintaining a firm grip on the rope at all times.

Cammed descending devices, such as the Petzl I'D, offer a significant safety improvement. These devices are designed to lock automatically when the handle is released, providing a fail-safe that older devices lack. For anyone using a descending device, the lesson is clear: never assume the device will stop for you—always maintain control of the rope.

The Rise of Combination Devices

The most exciting evolution in tree climbing gear is the combination ascender-descender. These devices eliminate the need to switch between separate tools for going up and going down. Popular examples include the Unicender, the Rope Wrench, and the Rope Runner—all of which allow a climber to transition seamlessly between ascending and descending on the same device.

These all-in-one tools represent a major leap forward in both efficiency and safety. They reduce the amount of gear on the harness, simplify the climbing system, and allow for smoother movement through the canopy. For climbers ready to move beyond traditional knot-based systems, a combination device is often the natural next step.

Final Thoughts: Building a System That Works for You

The world of ascending and descending tools is vast, but the principles are straightforward. Traditional knot systems remain the foundation and should be mastered first. From there, mechanical aids—whether for the hands, feet, or both—can dramatically improve efficiency and reduce fatigue. And for those ready to invest in a streamlined, versatile setup, combination devices offer the best of both worlds.

Whichever path a climber chooses, the golden rule remains: understand the limitations of each tool, never use an ascending aid as life support, and always maintain control of the descent. With the right system and a commitment to safety, the journey up and down the rope becomes not just a necessity but a pleasure.