Memos to self

Slightly stuck on the rescue dummy theme, I realise. Do not worry, I will move on to others, but I could not resist sharing one more…

I was on the road a couple days this week, running a aerial rescue session in eastern Switzerland. Don came along for the ride, he behaved and all went smoothly – maybe more about that in some future post.

I manhandled Don out of the van this morning, in a stroke of genius I strapped a skate board to the bottom of the spine board, which is great – so long as no one tells the kids!

Memo to self #1: Do not attempt to haul Don down the steep driveway to the cellar by yourself wearing the klumpen (wooden clogs) you were given after last year’s ETCC in Netherlands, or else DEATH BY KLUMPEN IT SHALL BE!

Memo to self #2: Do not unload Don just as your lovely, but also rather frail 94-year old neighbour is going out to do her shopping. You will most certainly give her a nasty old fright – QED.

Resilience, again

A couple of days ago, Nat and Stuart Witt dropped by for a visit, over from BC in Canada. We had a nice day together with loads of coffee and lots of chatting. One of the things we did was that we traipsed up the tower of the Münster, the cathedral in Basel. Considering it was built in the twelfth century in a earthquake zone, it has weathered the passage of time pretty well. OK, granted, during the great earthquake of 1356 the third tower fell in the river Rhine – but apart from that, I mean…

We were up the tower at noon when the bells start ringing. Stuart pointed out that the whole tower was moving, which I rubbished. To then realise… that the tower was moving! Quite noticeably so in fact. The movement of the bells cause the whole stone structure to move from left to right. For this reason, amongst others, the building was constructed with grouting which was softer than the red sandstone used for the construction of the cathedral – in the wind the towers sway up to a meter from side to side. Quite impressive considering they are 65m high, that is some oscillation!

I cannot even imagine how a medieval engineer or architect would have calculated all this, but it would seem they got their maths right.

Similar to aircraft wings or the towers described above, the movement of trees in the wind serves to dissipate energy. Rather than the movement being being unnerving, on the contrary, were the structure to be immobile and rigid there would be cause for concern. All the examples above are strategies in resilience, allowing the structure to deform under load and thereby withstand it, to thereafter return to a state of relaxation, the original form.

Like the aircraft engineer or the medieval architect, when the arborist considers an anchor point for rigging or climbing, for instance, he or she will be estimating the range within which the structure will be able to withstand load before irreversible or catastrophic change occurs.

After all, we want those towers to sway nicely, not fall in the river, metaphorically speaking! 😉

Ken has left the building

In my experience, rescue dummies very much live a life of their own.

Take Ken, for example, my stalwart Simulaids rescue dummy of the past years.

Every time I was getting ready to go someplace, everybody around the house seemed happy to lend a hand… until lugging Ken out of the cellar into the car came into play. He had a knack of inappropriate behaviour. One time one of his hands managed to come lose just as we were manhandling him past a box full of old crockery which was due to be taken to the flea market. Well, after Ken’s passage that crockery was reduced to lots of little bits. I suppose you could have always sold it as a puzzle! With a tube of super glue…

This was also one of the things I liked about Ken: he weighed in at a realistic weight. It drives me nuts when aerial rescue demos or training sessions are run with a dummy weighing 50kg (100lbs). I mean, really?! The risk being that solutions and techniques are identified which under real circumstances, with a average weight climber plus their gear, will simply seize up or prove to be otherwise non-viable. On the downside it did make him quite a lump.

So yes, Ken and I have been through a lot together. Any number of TCCs, workshops and events…

There was also that dramatic moment during ETCC in Turin where we ran a AR scenario where the casualty was stuck on a pole on spikes, meaning poor Ken spent his weekend on spikes on a pole. Which later on turned out to be a mistake, but more of that in a moment… anyway, in Turin, just before lunch break, Ken dropped a leg, making a touch of dramatic field surgery necessary.

Thinking of rescue dummies at comps always reminds me of one of my favourite stories in this department which happened during a comp a while back, when the climber blazed up the tree, slapped in an anchor point, bombed down to the dummy, established a load-bearing connection – to then snap his anchor point! The anchor point came screaming past him and the dummy, narrowly missing them… but fear ye not! The dummy rescued the intemperate climber.

Dummy 1, climber 0 😊 And so the tables can turn!

Then there was that time when Ken joined us for the ETCC party in Monza. Come morning he had vanished. We found him again quite a fair way away in front of Mat Glenn’s tent in some weird yoga position. The less questions asked the better.

Things really started going bad when recently Ken started shedding limbs as a matter of course. In the Czech Republic workshop a couple of weeks ago he got legless. I hate to think what would have happened had someone been standing underneath as it came down…

It turned out that over the years Ken’s joints have really gone to hell. I replaced three knee joints, now both hip joints were shot, as well as the joint between pelvis and torso (don’t bother checking, you don’t have one there, this is dummy-specific). So I decided that enough was enough. Time for Ken to move on.

Roll over Ken, welcome… Don!

Unlike Ken, who is a Randy 9000, Don is a bog-standard Rescue Randy. The difference being that the Rescue Randies have a steel frame under the plastic. In theory the ball joints on the 9000s reduce the risk of pinching fingers in joints, but in practice… well, see above.

Ahh yes, the charmed life of rescue dummies!

Insights and self-doubt

Last week I was able to run a workshop outside Vienna with Arbor Technical Institute Kreitl in Raasdorf, where I have not been for years. Good to be back there, really impressive outfit, loads of potential, very coordinated and extremely well set up.

I was working with a group of maybe ten people, quite a few of whom are trainers for Marcel Kreitl. This is a size of group I enjoy working with, the overall level of competence was high, allowing for interesting, lively discussion. The overall topics were planning for emergencies and aerial rescue, as well as a rambling discussion about resilience and creating it where lacking. Often as not, sessions like this will offer up a small gem of insight where you least expect it. This one was no exception.

When discussing resilience, I like to point out that part of what you are doing is weighing up safety margins and the ability of a system to buffer adverse conditions versus efficiency. In this sense, you can opt for maximised safety factors and large buffers – at the cost of efficiency. On the other hand, you could also go all out for maximum yield and efficiency, throwing caution, safety factors and buffers to the wind. The third option is that you weigh these various factors up against each other, maybe incorporating extra mechanisms or features, by doing so creating resilient systems, able to withstand load or adverse conditions, to thereafter return to a state of relaxation.

(Sorry, I realise I am being long-winded, I am heading towards the point I am trying to make, bear with me)

Whilst running aerial rescue scenarios, one of the techniques being employed was the counter balance for access line rescue. One of the climbers, a highly competent and experienced person, ran into an issue whilst performing such a pick-off rescue… he was running a friction hitch made entirely of high-modulus fibres. This hitch works fantastically for him in ever-day use, but when it came to attaching the splice side to the line to the casualty to be able to perform the counter balance, he was really struggling to get it to cinch down on the line reliable, in order to prevent himself from sliding down the line.

I thought this was interesting, as it unexpectedly showed how the resilience discussion even pertains to how you configure your friction hitch – which was not a connection I had made so far. Based upon the considerations above, you can opt for an ultra-reliable hitch, with a very high safety margin, but at the same time very low efficiency and lots of friction – making it highly impractical. Or you go for the bare minimum of wraps and braids, meaning you have to coax it into cinching on the line – with little safety margin, but in a sense higher efficiency (Mind you, a quick caveat here: it is debatable as to what is being used to assess efficiency here, so the analogy is not 100% correct. Arguably, a friction hitch which hardly bites cannot really be described as being efficient, as it is unable to perform as it should. The point I was trying to make is more the weighing up of safety, buffers and one measure of efficiency).

So it transpired in this instance that whilst the balance was well struck for a normal load distribution in every-day climbing, that the blend of materials of that friction hitch cordage did not possess sufficient margins to be able to create sufficient friction to hold a full body weight whilst installing the figure of eight prior to descent. This is not a general statement regarding high-modulus cordage, but proved to be so in this case, with this cordage combination, with this climber’s mass and this hitch configuration. In my books this is exactly why we need to practice aerial rescue – and therefor offers a valuable insight.

The climber in question was visibly disappointed with himself, feeling somehow that he had failed his rescue – mind you, after a bit of cheering up, the next day he ran it a couple more times, on different friction hitch cordage, problem solved. I cannot state it often enough that in my view, competent operators are not people who do not make mistakes, but rather are able to apply the appropriate tools and techniques to solve problems if and when they encounter them.  This climber ticked all those boxes, he persevered and resolved the situation.

It will always remain a mystery to me why it is that less competent people tend to over-estimate their abilities – whilst competent people chronically under-estimate themselves. Well, actually, there is of course loads of research into this phenomenon (in part described by the Dunning Kruger model), but still, when you see it playing out like this, you cannot help but be puzzled.

This is one of the reasons I enjoy these workshops: they feel worthwhile, allow me to work with teams and individuals, identify issues and develop problem-solving tools – as well as link up dots between topics where I had not seen connections before…

Image courtesy of Arbor Technical Institute Kreitl

En route

En route to Melnik, Czech Republic, to run a workshop.

I have been lucky and privileged to having been able to witness the evolution of the Czech arborist scene over the past fifteen year. Returning every couple of year has been like watching the process through in time lapse photography: From the early days when there was just a handful of idealists and pioneers, through to today, with a well established industry with youngsters coming to events for whom it is a given that an arborist industry exists.

What other industry offers the possibility to experience this kind of process first-hand?

On the way here I decided to skip a visit to the Mayday Motel… 😂 The mind boggles.

Climbers Forum impressions

After a tree care event, people will often say, it is about the trees. This always leaves me a bit nonplussed, as to me that is only part of the story. Working on trees may be a common thread, but the energy at these events comes from the people who come together for them and the passion they bring with them.

I therefore thought a post to highlight this was the least I could do to say thank to to everybody for supporting these events by turning up and freely offering their time and energy.

Thank you to Puk and Kay for the photos.


I had what might be considered a weird start to my week.

When we arrived on site, while I was getting my gear ready to get stuck into the first tree, I had a tune bouncing round my head, as one does. Buthold on, I realised, this is Careless Whispers by George Michael! I don’t quite know how to put this, but some things are best left in the eighties. This is most definitively one of them! How on earth did that end up in my inner ear?! Thinking about it, I realised that on my way to work I had cycled past a bird singing the exactly that chord of the saxophone intro at the beginning of the song – et voilà, the damage was done: song stuck in brain.

I reckon the bird was Georg Michael reincarnate, something which might look like this…

By mid-morning, I was going frantic, starting to fear for my sanity – not to mention the rest of the crew whom I was sharing my pain with. I decided in the end to try fighting pain with pain, so I gave myself a dose of Radio Gaga by Queen. Then shit got really weird. A messed-up eighties medley rattling round my brain – only gradually subsiding in the course of the day.

Whew. Thank you, Monday. What is in store for me for the rest of the week?!

Third day of Climbers Forum 2018 in Augsburg

The third day of Climbers Forum kicked off with a half day on habitat and retrenchment. Paul Muir of Treeworks Environmental Practice kicked off the morning, with an insightful and balanced presentation on retrenching techniques – very clearly differentiating them from topping practices. Phil Kelley was up next running through some of the work we did together in Green-Wood cemetery, as well as the planning and thought process behind it. Andreas Detter and Georg-Friedrich Wittmann discussed about protecting species we might expect to encounter during tree care operations.

The final half day a mix of topics, Thomas Böhl of fsb Örrel discussed the management of severe trauma and life-threatening blood loss. Max Olesko and Remy Gschwandtner ran a practical demo on throwline techniques which was fun. Don Blair rounded off proceedings with some reflections on Oak and Euc persons in arboriculture. Very entertaining.

Having said that, during the course of the day I was feeling more and more nervous about the looming tear-down, bearing in mind that it took us four days to get everything set up. In past years, tear-down consisted off everybody taking off, leaving us with a extensive pile of wet gear, in the rain and cold. I have unfond memories of fumbling bolts in elbow-deep water with a scum of ice on the top during the tower dismantling. Urgh.

Not so this year. We had a large group of people who hung around after the end of the last talk at four o’clock, allowing for a really fast tidy-up. Without mentioning names because I am sure to forget someone, you know who you are, let me say that I was profoundly thankful. We got everything pretty much stripped down by six thirty, meaning on Friday all that was left to do was to take down the tree and the tower, and dismantle the foundations, which we had done by midday.

Once again, I take away many impressions from this year’s edition of Climbers Forum. Moving the whole proceedings indoors into hall 3 proved to be invaluable, not just from the space it created, but also from a procedural point of view. It meant that there was a clear set-up, followed by the event, and then tear-down. Before, you were constantly forced to improvise and contingency plan, depending on the weather, herding people in and out, shuffle gear around – which made the event exhausting. So that merits a big thumbs-up from me.

I heard from one or two people that they felt that topics are discussed to death. View it as you will, but to me one of the aims of this event is to strive to gain a balanced, thorough understanding of topics. We are lucky to have many returning attendees, the majority of opinions offered during the event are reasonable. But the opportunity here is to use these people as replicators, identifying arguments and tools to take out there into the wild and wooly world of tree care, back to their work environments – by doing so creating a kind of domino effect. On top of that, there is enough superficial discussion in this world, all you need for that is a computer and an internet connection, so no, Climbers Forum is where topics are discussed with time and depth.

On a lighter note, during the event feedback forms are handed out. The return rate of these is notoriously low, which is a pity. But this year we got one back which made me smile…

FYI, Micha was DJing at the DMM party on Wednesday evening.

This begs the question why we go to all the effort of organising speakers and demos, when actually all you need is a deck, a PA system and a couple of hectolitres of beer 😂

So, lots of positives to take away from this year: New format worked well, the space in hall 3 felt welcoming and warm, lots of new faces, as well as old acquaintances, all speakers showed up and the content delivered was engaging and interesting. Now the only thing to worry about is how to go one better next year!

The dates for the German Tree Care Days and Climbers Forum are 7 to 9 May 2019. Consider yourself warmly invited.