How to SRT climb a tree and setting a lowerable base anchor system
Let's discuss two different SRT devices, how to ascend the climbing line, and setting a lowerable base anchor system.
How to set a releasable base anchor
After you set your climbing line, you're going to need a base anchor. In this case, a releasable base anchor rigged to facilitate an easier rescue if needed. What that means is that we're not isolating an anchor point in the top of the tree. What we're going to do instead is have the climbing line anchored at the base of the tree where somebody can rescue you by lowering you down if required.
So this base anchor sling is just a five-meter piece of Yale blaze with an eye spliced in the end and a DMM thimble. The reason we like this style of base anchor is the versatility it offers. If the trunk of the tree was any bigger, what we could use is our short climbing line, add the thimble to it, and you've just created essentially an infinite base anchor sling you can fit to any size tree. However, this 5-meter rope seems to do the trick for most situations.
We'll use a TAZ LOV3 as the device on the base anchor. It's a great little device and they work well for this setup. We're using it with 11.7 mm Donahue's Cougar Blue climbing line, which is slightly thick but it should work pretty well in the use-case.
Tie an alpine butterfly stopper knot in the base anchor rope, and tie an alpine butterfly stopper in the climbing line. Then clip them together with a full-strength locking carabiner. The alpine butterfly acts as a stopper knot and is there to prevent the rope creeping through the device.
Then if the climber needs to be rescued, someone can do so easily from the base of the tree. All they have to do is; unclip the carabiner, undo the alpine butterfly in the climbing line, and then lower you by using the handle of the TAZ LOV3 and their hand on the standing end (break side) of the rope to control your descent.
Another method is tying a slip knot, orientate the knot pulling from away from the device, and then turning that into a daisy chain of about four knots. Clip that into the anchor with a carabiner and that creates the stopper knot. To descend, unclip that first daisy chain and then pull on the tail to undone the daisy and then descend the person down.
How to setup the Rope Wrench
Let's set up a Rope Wrench climbing system on the climbing line, which will be familiar to 99% of arborists. We're using a "Knut" as the friction hitch. We like this knot a lot in 10mm Armor Prus because it can run fast and releases well, but it also consistently grabs. So it's a nice reliable knot, at least for an 80 kg body weight.
You're gonna need a neck tether, or something similar (chest harness) which will lift up your climbing system, and a foot ascender too. We're are using the CT Quick Step which is a really nice foot ascender. A knee ascender is also super helpful because it means that you can use both your left leg and right leg comfortably.
Lastly, you'll need a little bit of rope weight for when you start ascending. So I just tie one of those throwing knots. Start with a coil of rope then pass a bite through and choke it over the top.
Attach the knee ascender which is held in place by bungee cord and adjustable sling attached onto an ascender and goes down to a foot loop so you can easily use both legs.
And then, simple as that, you can walk up the rope.
To start working up the tree, all you have to do is detach your foot ascender, detach your neck elastic, and remove your knee ascender and you're 100% on your climbing system now. Simple as that.
How to setup the TAZ LOV3
Another common SRT climbing device is using a TAZ LOV3. This is the same device that we're using as the base anchor on the tree. The TAZ LOV3 is a really cool little device and it's useful for a lot of applications. It's not the best for tree work only because it's hard to be quite dexterous with it. But it's still a really good piece of kit, especially for straight-up access. This is because you can ascend on this and descend straight away without having to change over, or create a RAD system (that you would do to ascend with a Petzl I'D or a Petzl RIG).
So in one direction, the TAZ LOV3 ascends the rope freely and in the other direction, it engages the cam and locks in place. To descend down, all you have to do is pull the lever which releases the cam allowing you to smoothly descend.
Set up the device on the climbing line and use a neck tether to keep it oriented and capturing as much progression as possible. Use a foot ascender and take a few steps up and sit back down to get the device to lock. Now you can easily attach the knee ascender.
And ascending is exactly the same as the wrench, start walking up the rope. You may have noticed a bit of drag on the TAZ LOV3 when ascending compared to the Rope Wrench. But both of these devices work really well for this application.
Because we're located in a tropical environment in North Queensland, Australia, there's a high likelihood of having bees, wasps, hornets, and other hazards up in the tree. Having the ability to ascend and then descend straight away, without having to change systems, is really useful.
As previously stated - also having a releasable base anchor that allows somebody to rescue the climber when they're "on the rope" at any point during the climb is also very useful. So a groundie can descend the climber down if anything was to happen.
Thanks for making this this far! Hopefully, you got some value from this article. Let us know what SRT device you climb on, or would like to try out.