Belay Devices: Are they well suited for Tree Climbers?

There has been a lot of discussion about using belay devices for tree climbing. Many belay devices are lightweight and perform well for their intended uses. Products like the Trango Cinch and Petzl Grigri have made the leap from being a rock climbing belay tool, using dynamic or more springy rope, to a tree climbing progress capture device used with static or less springy ropes typically used for tree climbing. A belay device can also be used by a tree climber in a number of ways, including as a lanyard adjuster. Some go so far as to claim a device like the Madrock Safeguard (a hybrid belay device) can work as a tree climbing saddle’s rope-bridge adjuster.

My intention is to help educate and draw more attention to the similarities and differences between rock and tree climbing gear. I touch on the topic of non-conforming uses of gear, outside of a manufacturer’s guidelines. I’m not an expert rock or tree climber and my views may be taken with a certain degree of skepticism. However, I do my own research and accept responsibility for my opinions and views.

Tree climbers are resourceful when it comes to making things do what they may not necessarily be intended for or designed to do. For that reason, I will try to clarify things for beginners to better understand the trade offs when using belay devices for tree climbing.

As a rock climber is being belayed, the ground person uses a belay device that connects to the belayer’s climbing harness. Rope passes through the belay device, enabling the belay person to feed and retrieve rope or simply manage slack.

When considering the purpose of the belay device, there are two primary functions being addressed. The device locks onto and engages the rope when shock loaded and it enables the belay person to feed rope out or in through the device. The principle is fairly simple.

When a climber falls, it shock loads the belay device, which then engages or locks onto the rope, enabling the belay person to absorb the shock load of the falling climber and then feed more rope through the device to safely lower a climber back down to the ground. The weight of the falling climber is transferred to and absorbed by the belay person and partially by the dynamic rope absorbing the shock load. A belay person also helps the climber by managing the slack of the rope, by feeding rope in or out through the belay device during the climb.

Tree climbers typically use static ropes, without the same degree of elasticity of dynamic ropes used by rock climbers. A vast assortment of belay devices are currently in use and one of the two that have made a cross-over is the Trango Cinch. It’s no longer in production, but it supported larger diameter ropes used by many tree climbers. The Trango Vergo is the Cinch’s replacement, but 10.7 mm is the largest diameter rope it uses, based on the manufacturer’s guidelines.

The Cinch and GriGri, according to the manufacturer, offers a range of use by allowing a range of rope size diameters to work within the device itself. The GriGri supports ropes sized 8.5 mm to 11mm, and the Cinch 9.4mm to 11mm. Since tree climbers are known for pushing the envelop and by experimenting beyond what a manufacturer recommends, they’ve found that certain devices may work on certain larger static climbing sized ropes with varied levels of efficiency, contrary to the product manufacturer’s instructions and/or guidelines. Some tree climbers are more cavalier and do this solely at their own risk without first contacting the manufacturer to determine whether this is an acceptable risk. One may argue that there’s perhaps a 0.5 mm degree of variance, given the fact that a rope changes between the time it’s brand new and becomes more fully broken in, but using this or any product outside of the product manufacturer’s guidelines, is not recommended.

In the context of being used as a progress capture tool for a climbing lanyard, a belay device may perform well, notwithstanding the fact that, by design, a rope can move or be feed through the device when it isn’t engaged or tension loaded by the pull of the rope. For tree climbers, whether this can cause the rope to creep or slip unintentionally is almost a certainty, because that’s what a belay device is designed to do. Nonetheless if a tree climber is mindful of the device’s characteristics and maintains a consistent load on the device when in use, it becomes an issue whereby the climber assumes further liability and decides to set their own levels of risk tolerance.

Taking this a step further, a tree climber can use certain belay devices to capture progress on ascent, and as a rappelling device on descent. Since belay devices are not necessarily designed for the purpose of tree climbing, performance varies when compared to other assisted braking descending devices using larger braking cams. Opinions do vary and with the exception of the GriGri, many major tree gear retailers sell a more robust and fuller featured variety of assisted braking descending devices, like the Petzl Rig or ID, including many with built-in lock-off and/or anti-panic functions.

Tree climbers have an assortment of options when it comes to rope grabs, auto-breaking-descenders, even multicenders, all of which can be used as lanyard adjusters. Multicenders like the Akimbo, Rope Runner, Unicender and Hitch Hiker are in fact ideal lanyard adjusters, but maybe not as lightweight, compact, inexpensive and practical for the majority of climbers. I’m on a personal quest for the perfect all around, lightweight, multicending lanyard adjuster designed specifically for static climbing ropes with 11 to 12.5 mm diameters.

There are promising new designs for rope grabs in the works, one of which is a downsized Unicender, called the Hipster, which may be used to adjust lanyards, and as a foot and/or knee ascender.

The following video is several years old and new products and upgrades to these products are available, but the review discusses which types of devices are better suited and why belay devices are comparatively less effective when used in ways beyond their intended purpose.

Gear for self-equipped Tree Climbers

All this tree climbing stuff isn’t cheap, but here’s the ticket to being a completely self-sufficient tree climber:

This list includes more than a basic/minimalist tree climbing setup and it’s not all-inclusive or ultra-light, but it does provide a strikingly accurate glimpse into the type of climbing gear an experienced tree climber would likely use when traveling and climbing big trees, both locally and abroad.

I am not sponsored by anyone or paid to promote any particular item. The list below is based solely on my personal and budgetary preferences. I’d also be honored to test and review new gear, upon request. 

Much thanks goes to my buds at TreeBuzz, for all their valuable input and contributions to this list. While their valued opinions may vary, recreational tree climbers are similar, but different than tree care professionals. Rigging gear, chainsaws and climbing spurs are intentionally omitted, for that reason.

Rope lengths can depend on a number of variables. A lot depends on the average tree height, a climber’s technique, and whether the tie-in-point is in a canopy or basal. Some trees, including the Eastern Sierra Redwoods and Coastal Redwoods grow as high 300 feet, but the average tree height is 75 feet in most places, with many exceptions, including the Pacific Northwest.

Many agree at least a 120′ or 150′ rope length is adequate for most tree climbers. It’s lightweight and goes well with a packed climbing kits, suited specifically for hiking or perhaps air-travel. Static tree-climbing ropes are generally available in lengths of 120′, 150′, 200′, 300′ and even 600′. Various rope splicing options are also available at many tree climbing outfitters. Adding a sewn or hand spliced eye on the end of a climbing rope is a great option.

Some mechanical devices have a tendency to flatten a climbing line. Most work well on a broad range of static climbing ropes, while others like the Akimbo and Rope Runner can be more finicky on certain types of ropes.  Weather conditions can certainly effect the performance of various climbing devices, as well. When purchasing climbing rope/s, be sure the rope is well suited to your gear preferences and the environment where it will be used most often.

The following list provides an overview and a general guideline for the kind of gear used primarily for tree climbing purposes. The list is not all inclusive and certain items, like carabiners, may have multiple manufacturers producing similar products with the same functionality. Products in development, or currently available for pre-sale only, may be overlooked. As new items become available, I will try to keep this list properly augmented, but make no guaranties. Please use your best judgment when selecting appropriate gear for your climbing system.

  • Tree Climbing Helmet or an equivalent brain bucket (required): Kask and Petzl are a couple good brands to consider.
  • Tree Climbing Harness: My current favorite is the Petzl 2019 Sequoia SRT, but New Tribe has the Onyx, Teufelberger has the Evo and there are a number of other high quality, commercial grade, tree climbing harness available.  
  • Multicender:  Rope Runner Pro and the ZigZag-Chicane are my two current favorites.  Here’s more info about multicending devices.
  • A Knee Ascender, for SRT rope walking when combined with a foot ascender for the alternate leg.
  • Foot Ascender (right or left foot): CT QuickStep or Notch JetStep are my two current favorites.
  • Hand Ascender: Is easier to grip than the climbing line when ascending. Attaching a Roll Clip or a pulley of some sort makes a nice Rads, as does the CT Quick Roll Hand Ascender which adds a small pulley onto the hand ascender itself and is my current favorite.
  • A Chest Harness: Both the 4SRT and a Petzl Torse are nice lightweight chest harnesses, but an over the shoulder lanyard works for tending, as well. A more substantial chest harness may offer even more security and comfort when sharing the weight of the harness and gear resting on the climber’s hips.
  • Protective eye wear
  • Good climbing gloves, preferably not the finger-less ones
  • Lightweight high-top hiking boots to comfortably support a foot ascender.
  • Attachable Water bottle or a Camelbak – to mitigate dehydration.
  • 120′ – 300′ +/- static climbing rope – 11mm to 13mm / SRT &/or DdRT static climbing line. Lower diameter ropes are lighter, but larger diameter ropes are usually stronger and easier to grip with your hand.
  • At least a 15′ or longer rope lanyard kit, including the lanyard line, rope snap or carabiner and a lanyard adjusterhere’s more information about climbing lanyards.
  • A few double-auto-locking carabiners (Oval and/or D-Shape) for specific uses.
  • A few screw-locking carabiners (Oval and/or D-Shape) for specific uses that may not require using more expensive auto-locking carabiners.
  • Two 30″ Dan House rope sleeves or rawhide leather friction savers (aka: cambium savers). Certain types of friction savers may be better suited to certain types of trees.
  • Two stainless steel Delta Links for canopy tie ins, and/or Singing Tree Quickies.
  • A throw line kit, with one or two  150′ +\- bites of throw line for ground throws and another 75′ bite of throw line to store in a throw-line saddle bag while climbing and to assist with advancing a climbing line. I like the less expensive Target Line, a 1/8” diamond braid polyethylene line.
  • Two or more – 10 oz to 16 oz , preferably “unleaded” throw bags.

Extra Options:

  • Two Eye and Eye prusik cords with hand splices or sewn splices – 28″, 30″ or 32” long and 8mm to 10mm thick, as a rope grabbing lanyard adjuster and for climbing DRT and in case one falls out of the tree, or gets too sapped up with tree pitch (remove with Olive oil or WD40).
  • A Hitch Tending Pulley or a Micro “Pinto” Pulley.
  • Foot Loop; Singing Rock makes a nice lightweight footloop.
  • Descender – a Petzl Pirana, a basic Figure 8, or Munter Hitch on a carabiner serves as a backup descending device.
  • First Aid Kit, including a blood stopper bandage – compact kits can be worn directly on the climbing harness.
  • Bug Net drawstring bag, or Buff for head protection, in the event of unexpected bees or insect swarm
  • An assortment of Loop Runners of varied sizes, for rigging, assisted tie-ins, re-directs, etc.
  • DMM Captain Throw Hook Kit, or just a DMM Captain Throw Hook with a custom 50′ +/- lanyard line … here’s more about throw hooks, 2-in-1 climbing lanyards and secondary climbing systems.
  • A Petzl Rig, or another similar mechanical progress capture and descending device, for use in a 3:1 RAD, a rescue-able basal anchor, or with a DMM Captain’s lanyard.
  • A DMM Axis Swivel – or similar large eye swivel, for the floating bridge to help keep things untwisted and for enhanced orientations.
  • CT RollNLock, has many uses, including for use as progress capturing rope grab, a pulley, a rope bridge adjuster and in a 3:1 Rad system using a Roll Clip.
  • Anchor Ring, or an extra swivel, to use on a rope bridge and in various rigging configurations.
  • Headlamp
  • Folding throw-line cube, for feeding a clean throw-line on long tosses (reusable self-standing grocery bags are good too).
  • Big Shot (8′ tall slingshot), used with a throw bag and throw line to achieve  higher tie-in-points and with far better accuracy, compared to hand throws. Similar launching devices may include a crossbow, or a bow and arrow, usually with a spinning fishing reel to manage the throw line, or air cannons designed specifically for launching throw bags.
  • Tree Camping Hammock, Treeboat or Portaledge – rain tarp and bug net optional.
  • A lightweight plastic tarp or nylon ground sheet –  keeps your rope and stuff off the ground, dry, etc.
  • Go Pro, or similar, Action Camera for helmet mounted photos and videos.
  • Spring loaded, self rewinding throw line reel (Shapespeare Silent Tru-Art Automatic, Model No. 1837, with throw line used in place of fishing line).
  • Handsaw for clearing deadwood, cutting firewood and light pruning, when and where it may be expressly permitted.
  • The Tree Climber’s Companion, 2nd edition – a great beginner’s guide and reference tool.

Excluding the Big Shot, the above system fits into a standard size rolling duffel bag, in my case, weighing just over the airline’s 50lb weight limit. When traveling by air, some prefer to put the climbing hardware in a personal carry on bag, but getting gear through airport security can be touchy, so I prefer sending all my gear through checked baggage. By properly redistributing some of the weight, using a second piece of checked luggage, I’ve been able to meet the under/50lb weight requirement. Thereafter, I moved all the gear back into the one duffel size bag, for added convenience. Without the 10+/- lbs, or either the climbing rope or just the climbing hardware, my remaining gear weighs in at just under 50lbs.

Certain non-life-bearing (PPE) items noted above can be used or shared among a crew of climbers, and while many items might be considered optional, I still feel strongly about each item being a vital component of the overall system. Specific trees may warrant more or less gear, such as a giant Redwood, where the lowest branch to launch a line into far exceeds 100′. A climber must be able to adapt to individual challenges.

In conclusion, gear preferences do change and evolve as new products become available.  Tree climbing for research, recreation or sport has clearly a different purpose than for someone performing tree climbing services as a profession, although the two are not mutually exclusive, a tree climb without items like chainsaws and climbing spurs is far less risky.