There is nothing like putting a 50 tonne crane into overload at 9.30 in the morning to really get your day started.

But let us rewind back to the beginning…

We took down two Lombardy poplars last week, hollow at the base, with a considerable girth. The crane we were using was a Liebherr MK80, which is well suited to the urban environment we usually operate in, with very limited space, narrow roads and tallish buildings. The crane can get into pretty tight spaces, is affordable and fast to set up.

We were lifting the two trees over a building to a space in which we could further process the wood. The reach from the position of the crane to the trees was about 38 meters, allowing for a maximum weight of 2 tonnes at the furthest point.

We started the morning with a site safety briefing, discussing with all on site and the crane operator how we were going to run the job, who was going to take care of which task, how we were going to communicate, what the emergency plan was etc. As usual, the crane picks would be documented, we make a note of the number of picks, the estimated and effective load and also the orientation of the limb.

The weight we were aiming for at the outmost point was around one and a half tonnes.

Lombardies are not entirely straight-forward to rig. Especially at this time of year, when water is already being transported into the limbs, making these very heavy, so you are presented with trunk sections with long, heavy limbs attached. To avoid tipping and keeping it in the same orientation, you need to add quite a bit of trunk weight to the lower part of the section. Yet to operate within the defined weight range, there is a limit to how big you can go. We were attaching the chains low, adding an attachment point higher up to the limb to prevent tipping. Judging the centre of gravity correctly on picks like this is essential, as otherwise you can really get into trouble.

An issue we came up against was the fact that these trees were obviously drought stressed. In such trees, the water distribution is very uneven, leading to sections being  very heavy and waterlogged, whereas others are dry and light – this makes is very difficult to estimate the weight of the section correctly.

On pick four or five, when I had started to get a handle on the kind of weights we were lifting (I thought), I attached a section of stem with some long limbs on it, got everything ready, communicated the estimated weight to the crane operator, about 1.8 tonnes, got him to pre-tension to chains to 1.5 tonnes, got myself  in position… to then decided that it did not feel right, too heavy, so I went up and removed the chains off one of the limbs I had integrated, repositioned and got cutting.

I always agree prior to the lift with the crane operator how much tension he can put on the chains before we reassess the situation, this is to prevent too much tension being applied, when actually the problem is not the weight but that the cut is not all the way through, a couple of fibres can be all it takes to prevent a section from being lifted off. This is potentially a very hazardous situation as the fibres might suddenly break, resulting in the piece taking off, to then dunk down next to the climber. This is obviously a scenario you want to avoid at any cost!

When the crane attempted to lift the section, there was minimal movement, when I heard an ominous whistling starting up from the other side of the building. Argh, overload! Not good.

Not good, but it sounds worse than it is. Even when overloaded, these machines still have a safety margin, not massive and nothing I would speculate on, mind you. I was confident though that we were only marginally over the threshold, yet still, situations like this certainly get the adrenalin pumping. In such a case, a modern crane will go into safety mode and shut down until the load is decreased. I asked the operator to keep the piece exactly where it was, sitting on the stub.

Ok, Mark, you got this, deep breath, work your plan. Yes, thank you, inner dialogue, I am working on it! Not just hanging around looking – more or less – pretty.

I have a rule of never going on a crane job without packing rigging gear, because… you never know. Well, I was certainly glad for that foresight in this instance, as we broke out the rigging gear, attaching a Port-a-Wrap to the base of the tree and rigged a couple of the longer limbs off the section attached to the waiting crane. After we had thus removed two stems, I could see a bit of movement and we were then able to lift the section off the stub, towards the crane, where it could then be lifted over the building.

The piece was waterlogged and weighted in at 2.2 tonnes, minus the two limbs we had removed.

What this situation demonstrated to me was how it is essential to reflect your actions step by step. Move forwards one step, review what has happened so far. Does this feel right? If not, systematically identify and address the issues until it does. Expect the unexpected: When something unexpected does happen, again, be systematic and methodical, work through the issues and identify solutions. Have a range of options ready in your head – as well as physically a range of tools on site to sort problems with as they pop up.

Whilst the situation I described above was not pleasant, it was actually that big a deal, we  had it sorted out within 10 minutes, I apologised to the crane operator, who was actually fine with it (I think people operating large machinery tend to have heart rates like a blue whale, e.g. veeeeeeeery slow) and we moved on to the next section. Having said that, with a less experienced team,  who decides to simply bosh it out and to go for it, for instance by sliding the section off the stub, things might have turned out a lot less well.

I believe the other important point to bear in mind in situations such as this is to have confidence in your abilities and competence, the procedures you have put in place and the team around you. Do not be over-confident and cocky, but also do not allow yourself to become paralysed by terrible things that might happen. If I start to radiate insecurity and fear, it is likely to have a domino effect into the team, which is not helpful. Remaining focused and confident is more conducive to finding a solution, sometimes it is merely a matter of identifying the way forwards and putting the plan into action.

Oh, that was a total of twenty tonnes of wood we removed from that site. Not to mention the other two trees we removed on that day. I was tired afterwards.

When getting there at any cost becomes the only option

I mentioned target fixation in a post the other day. Here is a piece I wrote for this month’s edition of ISA’s Arborist News.

I find this topic fascinating and very meaningful, as it offers explanations for situations you encounter in daily work on a fairly regular basis. Certainly something worth discussing in your team.

And it goes like this…

When the going gets tough, our minds can play tricks on us, creating unexpected spots of selective mental blindness. The following article discusses the phenomenon of target fixation, the ways in which it manifests itself and affects us and possible strategies to combat it.

When fighter jets approach an aircraft carrier, the pilot is required to land a 24 tonne machine on a runway which is a mere 150m long by 20 meters wide, often during bad weather, in strong crosswinds or at night on a boat that is also moving at 30 knots. The arresting wire system slows the aircraft down from 240km/h to zero within two seconds in a scant 100m landing area. The men and woment flying these mulit-million dollar machines are highly-trained and competent. In order to assist the pilots, there are a multiple visual and aural guidance systems, aiming to ensure correct approach to the flight deck.

Despite all these precautions, accidents occur when pilots approach too low, resulting in the aircraft ramming the stern of the ship. Why does this happen? Psychologist refer to this pheonmenon as target fixation. This describes situations in which a person is scared, severely stressed or over-loaded, subsequently getting fixated on the target he or she is attempting to reach, blanking out the intermediate steps of how to get from here to there. This can lead to blind spots or blackouts, resulting in accidents such as an aircraft approaching the flight deck to low, despite all the precautions taken.

A further classic example for target fixation are the Fisher and Hall expedtions to Mount Everest in  1996, a tragic event revisited in Baltasar Kormákur’s 2015 film “Everest”. Scott Fisher and Rob Hall were both very experienced mountain guides whose companies enabled paying tourists to achieve the summit of Mount Everest. A fatal chain of events, involving amonst other things financial pressure, severe weather and a disregard of their own safety protocols led to both Fisher, Hall and a further six of their clients perishing on the high slopes of Everest, as well as several other climbers having to be resuced with severe injuries.

How could two competent and experienced operators make such bad calls? A central reason seems to have been that Hall went against his gut feeling, in an effort to assist his clients to reach the summit, despite having passed the defined turn around time, after which he should have returned to the relative safety of the advanced base camp. Fisher, it would appear, followed Hall’s example.

The more people have invested in an enterprise, the more they are susceptible to becoming fixed on a target.

An example for the arb world might look like this: In order to dismantle a tree, a crew have decided to install a speed line.

The installation is both equimpent and time intensive. Once they start speed-lining pieces out of the canopy, it becomes apparent that it is not possible to tension the line sufficiently to clear an obstacle below. In a case of target fixation, the crew, stressed out by the tree owner sceptically looking on, might decide to launch a really big piece into the line, despite the warning signs, to make up for lost time. This in turn could lead to a system failure, e.g. an anchor point failure. Simlar to the Navy pilots flying into the stern of the aircraft carrier, the arborist crew were fixated on gettting the limb from up into the canopy down to the ground that they blanked out the in-between steps. In such an instance it can be helpful to define turn-around points: If we have not achieved the result X by point Y, let us consider alternative courses of action. If the first reasonably sized bit does not clear all the obstacle, let us explain to the owner what the issue is and examine what our alternatives are.

Target fixation can be recognised by a number of symptoms:

  • The operator is determined that the target shall be attained at any price
  • The sense of a task it not questioned, even when difficulties start to accumulate.
  • Killer phrases are used increasingly, e.g. “This is how we have always done this”, “If it has been good enough for the past ten years, it is also good enough for now”, “end of discussion”. Killer phrases exclude any further discussion.
  • Alternative routes of action are not considered.
  • Danger is played down, risks are accepted that would usually not be.

A further factor which can be conducive to target fixation is planning optimism.

When the job was priced, the sales person based his or her price on the assumption that all would go as well and smoothly as possible, that the A team would be on the job and that the weather would be perfect. Yet on the day, all did not go smoothly, it was the B team which was sent out to get the job done and it was raining. In such instances, perception can become selective, leading to indicators of things going wrong being ignored and a type of groupthink, where competent operators influcence each other with their behaviour and this in turn leads to bad decisions (“the others were doing the same, so I thought it would probably be ok”).

What are strategies suited to defuse a target fixated situation?

For one to understand how and when it occurs. The closer one gets to a target, the higher the risk acceptance becomes – because the target is almost within reach and one has already invested a considerable amount of time and effort. Sometimes a controlled emergency landing is better than a crash: in case of having misjudged the size of the limb being lowered in the rigging system, it may be better to let the piece run and smash the marble fountain below rather than risk compromising the climber’s anchor point by suddenly decelerating it. It is imporant to observe your innner dialogue and to pay attention to warning signs. Defining and observing turn-around points can be helpful to keep a route open to alternative plans of action. And finally, keep an eye on risks, bearing worst-case scenarios in mind.

Check lists, documentation and encouraging and practicing a good communication culture are central to preventing teams from becoming trapped in situations in which the target becomes the primary and only consideration – and all else gets blanked out.

Lastly, give it a name: target fixation, learn to recognise it – and to defuse the situation by taking another route to attain your target.


Finally, we got round to filming the treeGONG, the 3D acoustic surround ascent termination announcement aid in action.

You may remember, I wrote about this concept a while back, see for yourself how it works in real life! Big shout goes out to Pyšná, an early adopter who placed the first pre-order. Next, the kitchen sink.

Hey, I might try to Kickstarter this one! It certainly does not make any less sense than some of the other stuff out there…


Thanks to Vito for the filming and video eds, also to Florim and Laurent for bearing with me.


Target fixation

We had one of those classic situation yesterday, the sort you often talk about, but rarely encounter in such undiluted quality…

Mid-morning, still working our way through the plane tree alignment, we were three climbers up two trees, loads of hung-up, suspended branches. Four town employees, all high-vizzed up were doing ground work and keeping an eye that no one enters the cordoned off are. We had scissor fences up, the ground was littered with braches, plus barrier tape.

I heard some commotion on the ground, people shouting, and all of a sudden Vito, over in the next tree starts hollering. Quod the… ?!

I look down and see a senior citizen, fully kitted out in a track suit, two nordic walking sticks and big over-ear headphones on, totally unperturbed by all the hullaballoo going on around him, skipping the scissor fencing, weaving his way through the branches, dodging the city boys, heading right towards where we were working.

Umm, yes.

Finally, two of the city bods physically blocked his way, I could see him gesturing in a very vigorous fashion in the way he obviously intended to proceed, which on that morning happened to be right below the trees we were working in. Not to be put off by the risk of being buried below a gorilla nest’s-worth of branches, he shoved the guys to one side and took off again. I was literally holding my breath… until he was clear of the canopies, carrying on his way. Unbelievable.

Expect the unexpected and all that is all very well. But this really took the biscuit. It was like watching a really hazardous situation evolving, totally helpless to do anything, other than hope that the branches suspended would not chose that exact moment to come loose. Which, luckily, they did not.

Probably, he does his nordic walking spin every Friday, on exactly this route, and there was no way he would be deterred from doing so today by a bunch of tree guys!

Whilst there may be a comic element to this story, there is of course also a darker side to it. If the manic walker had been hit by something, taking the attitude that all the blame is on the crew of the town might well not fly. It is not as easy as saying that all which I am responsible for is up above, all which happens on the ground has nothing to do with me. A friend was involved in a similar situation, where he was working for a town, dropped a stump, which was deflected by a limb, to hit a passer by (who happened to be a lawyer). Despite the fact that employees of the town were in charge of the ground, the guy went after the person in the tree. An unpleasant business, on all levels.

Apart from the fact that we were obviously dealing with a stubborn old boy, another major factor in this situation was target fixation, a very interesting topic I wrote a piece about for this month’s edition of ISA’s Arborist News – I will pop it on the blog once it has been published.

So, I guess the points I take away from all this (once again) is to be alert at all times, talk to the guys on the ground prior to starting aloft, making sure they have done a thorough job of closing off the workspace, and finally, to check and give a warning before dropping anything major.

Man up

After reading yesterday’s post, you may be thinking to yourself, This guy really is living in an ivory tower, he simply needs to man up and get on with it instead of whinging about it behind his computer…

Well, to that I would say that there is always a degree of subjectivity to these things. But regardless of that, I am a firm believer in the fact that niggling doubts, a funny feeling or self-doubt need all not necessarily be negative, if seen in the context of checks and balances.

One response of the body to being dumped in an exposed or unusual environment is alter the chemistry it produces: Catecholamines, such as Dopamine or Noradrenaline prime our bodies to respond to stressful situations, ramping up metabolic functions, such as breathing and heart rate, making us more alert and responsive. All of the above can be put to good use, as an aide to ensure we are implementing our plan correctly and to help us avoid making mistakes.

Actually it would be quite strange, and rather ignorant of the potential risk these situations entail, to simply go swanning into a job on a large tree or a technical dismantle as though you did not have a worry in the world, taking the line that it’ll sort itself out.

A heightened sense of awareness at all levels is a very useful thing to have in such a situation, on the condition, as I said yesterday, that the effect it has on you is not a paralysing one, but rather one of focusing on the essential things around you.


Let’s talk about height

Carrying on the theme of big trees, we are now on to the third day working the alignment of large plane trees I was rattling on about the other day

I can confirm that they really are big. We were maxing out the Big Shot for throwline installation, 60 meter (200 ft) lines were only just long enough, so were the access lines. This got me thinking about how I actually perceive height when working at greater heights.

So let’s talk about height.

First off, I would suggest that the way we perceive height is influenced to a large degree by context.

Whether you are at 10’000 meters in a plane, at the top of the 300 meter Eiffel Tower or 40 meters up a tree will feel different in each instance. This has to do with the way in which we are exposed to height: in a plane we travel cocooned in a shell of aluminium, plastic and insulation material, on a structure (unless you are a telecom technician) we are usually protected from a fall by thick panes of safety glass or fencing. In a tree you have just ascended, height is much more immediate and tangible. I also find myself being very aware of the fact that all which lies between me and oblivion is 12mm of polyester.

What I have found helpful in such situations is the rule of not letting fear rule your actions, but rather for your actions to rule fear. By actions I mean following your training and protocols, by carefully thinking through each step and taking into account what might go wrong. By taking control of the situation, by owning the space you are moving through.

Having said that, not each big tree evokes the same emotions. The sensation of height up a very tall Sequoiadendron, where you are surrounded by foliage is totally different from what you will experience up a tall plane tree, for instance. I was talking about spatial awareness the other day, the x, y and z axis… well, immediately after ascending into a tall plane tree and having installed my anchor point, I am aware of the z. There is loads of the stuff below me! Empty space à gogo!

At the beginning of big climbs, I sometimes find myself in a “noisy” headspace: niggling doubts whether the these lines , my rope bridge or these connectors are really up to the job, whether I may have overlooked damage to the tree below me, a cavity maybe, or a fruiting body – and also self-doubt whether I am actually up to the challenge.

I find trusting my experience, my tools and the techniques I employ, allows me to push through the static and start exploring the structure, which I find fascinating, as it is so different every time, different from tree to tree, different structures, challenges and solutions. Focusing in on these points allows me to achieve a state of almost serene calm, totally immersed in the climb, where one movement leads to the next with a great sense of clarity, with height now no longer predominant, but simply part of the environment I am moving through.

A state of flow, as Mihály Csíkszentmihályi would probably say…

 A major factor in how you experience the above will be the crew you are surrounded by. If these are people with a can-do, positive attitude, who are prepared to get stuck in and get the job done, with every person contributing what he or she is able to, this is going to make a major difference.

Sometimes I am puzzled by attitudes I hear in our industry, people telling me about how their aim in life is to have ten employees and stop climbing or how damaging climbing is, the wear and tear it causes. While to a degree this may be true, I believe that movement is a privilege. The idea of spending my days cooped up in an office gives me goosebumps. Sometimes I will bring niggles, aches or pains to the job, knowing that a days climbing is what I need to sort them out.

Yes, of course there are those days when it is a struggle and everything hurts afterwards, I am not denying that. Yet there are also those other days, when everything falls into place – and they are most definitively worth chasing and cherishing.