Among the “rules” passed along to beginners taking a Basic Tree Climbing Course (BTCC) are those stating that one “should never climb on a dead limb” and another stating that one should climb on limbs “at least four inches in diameter and no more than one-third the total length of the limb away from the trunk”. The rule about limb size and distance from the trunk might vary a bit from instructor to instructor, but you get the idea: Don’t climb on small limbs and don’t go setting your rope too far away from the trunk.

Well…yesterday we were supposed to be doing a climbing program with a group of sixteen climbers. We had rigged our favorite white oak with sixteen settings, tied the knots, and done all the other things we do before starting a climb of this sort. Then we sat back and waited for the group to show up. Only they never showed up! Two hours of rigging and nobody to climb.

Not wanting the day to go to a total waste we---that is WildBill, SwampFox, and myself--- turned out attention to the tree next to ours. This tree, another big oak, has been dead for more than five years and has been steadily raining dead limbs and shedding dead bark since it died. Looking up among the remaining leaders and branches all you can see is a whole lot of dead wood with a whole lot of fungus growing all over the place.

Some of the dead limbs hanging over our heads are dangerously close to our program tree and we have worried now and then about the possibility of one of the big dead leaders crashing to the ground while a program is in progress with lots of kids running around the area.

So…we decided to see if we could throw a line up and over the one that looked the most dangerous, put a rope in place and then break it off and let it fall. WildBill got a line up in record time and we hauled a rope up. SwampFox grabbed hold of both ends and began tugging. The limb was shaking but wouldn’t break. WildBill then added his weight and it still wouldn’t break. The whole tree was shaking but nothing was giving way. I added my weight and it still wouldn’t break.

We then tied one of the rope ends off, meaning that we would then be placing double our combined weights on the rope, the equivalent of six people’s weight. Nothing gave; nothing even started cracking.

Now you have to understand that this tree has been dead for at least five years. The placement of our rope was at least twenty-five feet away from the trunk and the leader, at the point where we had our rope, was maybe only eight inches in diameter. The thing should have broken!

So…we decided to go one step farther. Out came a couple of double pulleys and we rigged a four-to-one system to our already existing two-to-one system. I’m not an engineer or a physicist so I will allow Ron to correct me if I’m wrong, but according to my calculations this rig was giving us a four-to-one acting on a two-to-one, resulting in a mechanical advantage of eight-to-one.

We started hauling on the system. The limb moved, the tree shook, but nothing broke. Nada! If my calculations were right this meant that the three of us were acting on that leader as though we were twenty-four people!

That’s when we gave up. We decided we could give it another try next year!

Returning to our already rigged program tree, I decided to get in a climb. I re-rigged the DRT setup for SRT and started up. Reaching the top of the seventy-five foot pitch, I was amazed to see that the rope was not resting in the “main” crotch, but was, in fact, over a small pencil-sized limb about six inches above the main crotch. This pencil-sized limb was flat out dead! It was not a particularly dangerous situation. Had the little limb broken it would have resulted in a drop of no more than six inches into a really bomb-proof setting.

Neither of these events is going to make me go out and start climbing on dead limbs or on pencil-sized dead limbs, but it is certainly making me wonder about just how much we could get by with if we chose to ignore the rules!

I am not planning on ignoring the rules. I would not climb on a dead rotting limb even if it could hold more than twenty-four people. And I am not going to intentionally trust any pencil-sized limbs. Ever!

And I will still teach the rules that climbing on dead limbs is a no-no, and that limbs should be at least four inches in diameter and that settings be no more than one-third the length of the limb away from the trunk

Just food for thought!

Why knot take up a small arborist hand saw and take out a few of the weaker limbs at a time. Everytime you climb, thin it out a bit. Is it on public or private land? If it is on public land please disregard the saw unless you get permission.

Also, you would double the force on the branch if you use an SRT sort of system with a trunk tie off. It would be much easier to use the saw. Either way be careful. Falling limbs hitting you on the head hurt no matter how you dislodge them.

Word of caution. Before you take a saw up watch this video first. Always tie in twice while using any saw.

http://www.youtube.com/watch?v=YhEGpamZBJ4

Safe climbing

BKS

great video!

The first time I saw a climber tie into a dead limb I called him out, he had 30+ years experience climbing and laughed at me, "No way you can break that limb hanging on it". I think the answer is that it takes a lot of climbing hours to learn to understand what's safe and what isn't. In that situation the climber wasn't climbing from the ground on a dead branch, he was at the branch and could sound it by smacking it and could inspect it visually. As another climber once said to me, "a wooden chair is made of dead wood". I still won't tie into dead limbs as primary support, I will tie into them once in awhile with backup either around the trunk or on a second live limb.

Species like white oak are a whole 'nother matter, I think many climbers have experienced getting their rope hung over a pencil-thick oak branch/sprout and can't bust it out. I've read a few reports of experienced arborists seriously injured or worse when a live branch failed and dropped them. In several of these incidents the cause of the failure was that the rope moved out away from the union on a small diameter branch while they were ascending and failed from too much leverage exerted. As always vigilance and reasonable caution are a tree climber's greatest safety tools.
-AJ

So let me see if I understand this correctly. You intentionally left a leader standing that could fall on someone in a class?

Joe the image I have in my mind of you guys doing that is making me cackle! Who would have thought! Well, I would have but then I'm always right.

I'm doing the math now, where did I leave my scientific calculator??? Let's see you have 2 somethings pulling on 4 somethings, wait that's not right, you have 3 somthings, pulling on 2 somethings, pulling on 4 somethings, errrr, was it 4 somethings pulling on 2 somethings pulling on 3 somethings. Hmmm, it's a good thing this calculator does calculus.

Hmmm, my calculator is electrical based, but it says the 3 somethings were short circuits????

Boy, I'm in a feisty mood today - probably coffee deprivation.

The Ron

We left it there for you, Ron, but you've never shown up for the climb!



I use an abacus myself. It's a lot more reliable!

So...since you're picking on me....I will pick on you!

WHEN ARE YOU GOING TO WRITE SOMETHING FOR THE ARTICLES PAGE????? a QUICK LOOK AT THE "MEMBER LIST" SHOWS THAT YOU AND MOSS HAVE WRITTEN MORE COLLECTIVELY THAN ALMOST EVERYBODY ELSE TOGETHER. WELL...ALMOST! YET NEITHER OF YOU HAVE EVER SENT ME AN ARTICLE FOR THE ARTICLES PAGE.

Being a scientist of sorts, surely you could come up with something. How about an article on Chaos Theory and its realtionship with ZingIt throwline? Or...how about an explanatory piece on why String Theory has absolutely nothing to do with throwline? Or...is the Einsteinian Theory of Space Curvature an adequate explanation for why throwbags never go where they are supposed to?

Allright...it's a rainy morning in Georgia and I think I'll go see SwamFox at the coffee shop. Whatever!

The abacus is why China is going to rule the World. Watch this video to see what they are doing with it.
http://youtu.be/wIiDomlEjJw

Thanks for that link Bama!

There you have it, Ron! Get yourself an abacus. Not only will it help with your calculations but it will allow you an excuse for buying a new piece of gear that you can add to your collection of other gear. Besides...how many tree climbers actually own an abacus?

You could then try to coerce all the rest of us to go buy one ourselves.

Which is what you are best at.......

Now see, there you go. I try to help and what do I get - grief.


Hey don't feel like you need to thank us; you know how selfless we are.

I like the Chaos theory about ZingIt - that sure explains some experiences with it:
http://www.youtube.com/watch?v=nlZX10l1T6Y

I promised a guy that I'd do a video or two on limb isolation techniques; is there already an article on that?

Hey, wait a minute, why do moss and I have to do every thing. Hmmm, I did a 17 segment series on pulley systems, that'd be a good article. Have you seen them or is your computer still connected to the web with cans with a tightly stretched string between them?

This is not a post

This isn't either, a post that is.

Yeah, and I am half of the collective other posts...