Page Contents:
Overview
SRT (Single Rope Technique) is a rope climbing method. This page covers JRB’s non-mechanical SRT climbing method, its principles and why and when we might use it. See the dedicated YouTube playlist: JRB SRT
For the details/options for creating a Climbing System which allows SRT, see the following pages. JRB recommends building a 3 Hitch System over a dedicated SRT system, given its ability to climb with the Hitch Climbing Method also:
Non Mechanical? How?
The majority of the climbing community (including the arborist community) is under the assumption that an efficient SRT climb requires mechanical devices, and that an efficient SRT climb without mechanical devices is NOT possible. Watch this 60 second demonstration to see what is possible!
This was JRB’s first video on SRT, demonstrating that non-mechanical SRT is POSSIBLE and EASY.
Below are the key challenges solved by JRB to enable non-mechanical SRT as a viable method:
- In order to smoothly transition into rappel, we need a friction device which can be released under the full load of our body. Traditional friction hitches used by climbers/arborists do not allow this. They may perform adequately in MRS (with half our weight), but not in SRT (with our full weight). JRB has solved this problem with the introduction of better performing friction hitches like the JRB Ascender, Longhorn Agile and Formula Hitch.
- Unlike MRS which can handle using the friction hitch as a rappel brake, in order to rappel in SRT, if we attempt to burn off the friction on our hitch, we run the risk of it overheating, jamming or wearing prematurely. JRB has solved this by introducing a 2nd bridge, where we can attach our rappel friction device (Munter, figure 8 or whatever). Although JRB recommends dual bridges, if on a one bridge saddle, JRB has also demonstrated how we can fit a Munter onto the same carabiner that is engaging our friction hitch.
- In order to get our weight on our feet while ascending, the only types of footholds available were mechanical in nature (such as knee and ankle ascenders). JRB has solved this problem with the Garda Hitch footloop.
When to consider mechanical
In the following situations, mechanical systems may be advantageous:
- Arborist production climbing. Arborists are constantly moving around in the tree and want to reposition and redirect with minimal fuss. They also use large diameter ropes and have a ton of great devices to choose from.
- High climbs. When we climb with a Garda hitch footloop, we need to lift the rope with every step. As we get higher, that is more and more effort due to the weight of the rope. At the height that a hunter will ascend, it is not a problem. But a recreational climber going to 100′ will feel the difference in lifting that much rope.
Throwball
Getting our rope in the tree for SRT generally involves the use of a throwball or paracord preset. Be familiar:
Garda Hitch Footloop
JRB recommends the Garda Hitch Footloop for all SRT climbing:
Anchor Required
Unlike DSRT or MRS climbing, when using any form of SRT, the rope must be anchored to the tree. There are three types of anchors for SRT, described below:
- canopy anchors
- basal anchors
- floating anchor
Canopy Anchors
A Canopy Anchor is an anchor which is above the climber, typically in a strong tree crotch, but can be anchored on the trunk or both. The canopy anchor must be retrievable, such that the climber can get the rope down after rappel. Leaving a climbing rope in a tree for any length of time is not recommended. JRB Recommends canopy anchors unless the situation requires a basal anchor. Options:
Basal Anchors
A Basal Anchor system is one where the anchor is secured at the base of the tree, with the rope routed up and over a secure support point (crotch) in the canopy. JRB recommends that we consider basal anchor SRT only when we cannot use a canopy anchor. Why?
- It doubles the load on the crotch.
- It requires more rope, even more than DSRT.
- It requires tying a life sustaining knot at the tree.
- Anything on the base of the tree can be noticed by deer.
Rope rigging details:
- Using the throwline or paracord preset, one end of the rope is pulled up and over a strong crotch in the canopy and back down to the base of the tree.
- A basal anchor is formed on the trunk with one end of the rope and the other side is used to climb. Basal anchor choices are described on the trunk anchors page:
This video explains the load doubling effect. Also see Scenario 8 below.
This video demonstrates the 3 situations which may warrant a Basal Anchor configuration: 1) branches between the lines 2) for achieving a preferred position/direction in the tree 3) Avoid getting a throwball stuck in a messy tree.
Floating Anchor
JRB devised a “Floating Anchor” as a type of Canopy Anchor, which is set on the trunk. Floating anchors should only be use on trees which will be climbed multiple times and have no natural crotches which are adequate for climbing support. See page:
Advantages of SRT
These are the main advantages of SRT over DSRT:
- Can be accomplished with less rope.
- Easier ascent technique: its easier to advance one hitch than two.
Disadvantages of SRT
These are the reasons that JRB prefers to use DSRT over SRT in all other situations:
- Climbing on a single friction hitch puts twice the load on the rope and the hitch compared to a doubled rope system. This increases the risk of the hitch slipping OR in breaking the hitch to initiate rappel.
- SRT requires a life-sustaining anchor, which introduces some amount of risk.
- Rigging and setting up system for SRT is more complex than DSRT. Details may vary, particularly if knots need to be tied at the climbing site.
- SRT requires bringing a retrieval cord and some extra steps in retrieval.
Supporting Demo’s
Technique and Geometry
This video covers SRT and DSRT, from the perspective of different experience levels.
Single Rope Rappel, one Bridge
Before we climb, we need to think about how we will rappel. This demonstration of rappel on the Munter Friction hitch is on a single bridge saddle. (JRB prefers dual bridges.)
Single Rope Rappel, Dual Bridges
This (older) video shows how it is done with the recommended configuration of dual bridges.
Reasons/Situations for SRT
Wherever possible, JRB prefers to use DSRT given the advantages explained on the DSRT Method page. However, the following situations are valid reasons or situations to use or consider (non-mechanical) SRT. (Italic text represents a scenario not yet covered on video.)
Preference for Minimal Rope
On a typical tree, using a canopy anchor setup, it is feasible to execute an SRT climb with less rope than DSRT. Simply put, some prefer to carry less rope and accept additional complexity and time to rig and retrieve the rope. As demonstrated, A 3 Hitch System (or a dedicated SRT System) can be preconfigured with a JRB Bowline to allow SRT climbing without any knots tied at the climbing site.
Improvised Short Rope System
If we are starting with nothing preconfigured, we can build an SRT system on the spot with just one friction hitch and canopy anchor. Below are two similar demonstrations.
This video uses a quick link in a sewn eye as the canopy anchor:
In the following video, the Maverick Hitch is used as a canopy anchor and allows passing the end of the rope through the Maverick hitch as it runs up the tree. Note: The Super Maverick is preferred for this configuration.
Crotch too high for DSRT
Consider that a 60′ (Hybrid) system can be converted into SRT mode to climb a crotch over 30′. Similarly, an 80′ (Universal) system can be converted into SRT mode to climb a crotch over 40”.
Horizontal crotch angle
If throwball or paracord preset is over a sturdy, but horizontal (or sloping downward) branch, if an anchor is formed in the crotch, the rope might pull away from the trunk as the climb is executed. It is better that the canopy anchor captures the trunk.
This is the same as scenario 4, but if the tree and the adjacent woods allows it, we can flip the rope over the branches to get it into position and capture the trunk.
Branch is dead or too high: Houdini Rigging
If the throwball is over the first branch on the tree, but it is either too high or not viable for support, the best option is to capture the trunk with a horizontal and cinching anchor using a Houdini Maverick as the canopy anchor. This situation is especially prevalent in pine forests. Note that this method will not work if there are branches lower down on the tree, impeding our ability to advance the anchor.
Physical Ability
In the demonstration below, the principles of mechanical advantage are used to create a non-mechanical 3:1 RADS (Rapid Ascent / Descent System). Although this system was designed for a physically handicapped hunter, it also might be of interest to a person of limited physical strength or capability.
Branches between the lines
When we have branches between the lines and cannot easily isolate them to leave our rope over a single crotch, it’s often easiest to use a Basal anchor SRT technique on the 1st climb and rig the retrieval to ensure that when the rope is retrieved, a DSRT preset is left in its place.
No crotch: Floating Anchor
When a viable crotch is not present on the tree where we want it, the tree can be climbed the first time using another method, and a Floating Anchor can be installed in the tree, allowing SRT in the future. Note that this works on a tree with or without branches under it, where a Houdini Rig will not. In this demo, the floating anchor installed in a prior Hitch Climb was left in the tree, enabling an SRT climb with a Maverick Hitch as the canopy anchor inside the floating anchor.
Tight Crotch: Abandon Hitch 1
When using a long rope system, if the crotch is too narrow/tight to allow the passage of a friction hitch, we can abandon friction hitch #1 and climb on hitch #2.
Houdini Rig on Floating Anchor
Note: This has not yet been filmed. Note that it only works on trees with no lower branches.
Positioning
In DSRT, the climber ascends directly under the center of the crotch. If we wanted to face a different direction (as demonstrated in Scenario 8), a long rope system and basal anchor on a wide crotch allows us to position ourselves under either side or the crotch.