Tree caving in an 800 year old yellowwood

Leon Visser

October 2014

 Imagine climbing an ancient yellowwood tree, never before ascended, and enjoying the feeling of height and space. Imagine caving- it’s dark and unknown down there with who-knows-what waiting in the depths.   Now imagine the surprise of finding a cave IN A TREE and climbing up in the light and down in the dark. This was my experience with 2 fellow climbers in an ancient yellowwood tucked away in the indigenous forests of Natures Valley on the southern Cape coast of South Africa. dscn1259

Ascending an ancient yellowwood

Our mission was originally to climb and measure this old specimen for the Champion Tree Initiative. We had an idea there may be more to this tree than met the eye, as I had ascended it almost 2 years before to retrieve a lost throwline of Cameron’s, one of the climbers. While up there in the light drizzling rain, I discovered what appeared to be a sizeable cavity from an ancient limb that had rotted into the trunk. At the time all I could do was squeeze in up to my shoulders, but being alone and with no backup or torch, I wisely bailed …but not without wondering what else this tree may be hiding, and vowed to myself that this tree had to be re-visited.

So it was that a year and a half later, the three of us – Terry, Cameron and myself got some time and gear together to tackle this tree. We wanted to measure its height and needed to climb it to do so. It was perfect spring weather in the forest that day – warm, sunny and calm.

We got our lines in with a bit if a fuss, using weighted throwlines to pull our climbing lines in place. From there, we quickly ascended our ropes using rope ascending techniques to the first anchor point about 16m up into the canopy. I made a bee-line for the hole, and to my surprise it looked like there was a deeper cavity than I expected. The entry hole was tight, so I took all my unnecessary kit off my harness except for a camera and 2-way radio and wiggled down, kicking some of the loose dead wood and accumulated debris free. In the darkness it sounded quite a way as the stuff tumbled to the gloomy depths below. I abseiled cautiously into the ever widening cavern, not sure what to expect. Where there animals down there? What bugs spiders and bats may be lurking? I was completely amazed that in fact this was a hollow tree over 2m thick. As I descended, there were shafts of light streaming in through some old rotten branches that had left little windows in the tree wall. After 12 meters I looked up in to the now small tunnel of light above me and called out to the lads above me. dscn1208

   The cave hole entrance

 “Hey, Terr! This whole tree is HOLLOW! You and Cam must come down!” I shouted excitedly.

More debris rained down on me as Terry descended, and I had to hide n a small side cavity. The only way to see further below was to use the flash of my camera – having foolishly left my headlamp behind at our camp spot.

“I reckon we can go all the way to the bottom”, I ventured to Terr.

“Lets do it!”

We each descended further for a few meters until our feet touches soil - we were right at the bottom of the tree – inside the trunk!. Cameron sent down a line so we could measure the depth once out the cavern. Next, he abseiled down, also on his own line.

Soon all three of us were standing at the bottom of the tree – wide eyed and totally amazed at what we had just discovered! - we were 15m deep in the tree!

“THIS IS CRAZY! We are in the middle of an ancient yellowwood!”

“We need to document this“, said Terr.  

“Yeah – and we should have brought coffee”.

“Next time, for sure!”



Leon descending into the depths

 By this time, a friend, Willie Brink had arrived so were able to communicate via 2 way radio. We established that we were in fact on the ground by knocking on the inside of the tree, with Willie correspondingly knocking on the outside.

It was time to ascend up our ropes into the daylight which proved more awkward using the climbing system we were using. Next time ascenders and a pantin!


 Terry looking into the hole


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Leon peering out of the cave hole

This was only half the adventure. Once out in the sunlight and after a few Bar-Ones and some water, we started moving up the massive trunk higher up into the canopy. This proved difficult due to the scale of the tree and the complexity of its structure. Using our throwlines and carefully advancing our climbing lines we steadily edged our way and eventually I could stand almost at the very top. Terry followed and Cam went up a slightly different way. img 2300


 It was time to measure this magnificent tree, so we radioed for the tape which Willie tied on and we pulled up. It measured 29.85m in height and 6.4m in girth (2m diameter) and a crown spread of 29m. It was as wide as it was high – but completely hollow. No one would have guessed this, and there was absolutely no way to have discovered this without having been able to physically climb the tree.

What an amazing thing – an 800 -100 year old tree – hollow and yet fully healthy and functional. How long it will still stand is a mystery. Hopefully for many more years.

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 Cameron (left) and Terry (right) hanging high up in the yellowwood

 There is a concern I have about the extent of the creeper which is steadily enveloping this wonderful tree to the point where it could completely smother it. This calls for some carefully considered action, and should not just be left for nature to take its course. The tree is too special to be simply left. Will SANPARKS have the will and the foresight to tackle this and some of the other trees in the valley which are also being smothered? Time will tell. Who knows what other treasures lurk in the ancient yellowwoods of the indigenous forest?

To my knowledge this is the first tree climbing caving expedition in SA. Thanks to Len Du Plessis of SANPARKS for permission to climb an measure the trees.

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Mission accomplished! The tree climbers from left to right Cameron Brand, Leon Visser, Terry Grimbeek