I thought it might be useful to get people's assessment of the differences between tree climbing and rock climbing/caving as that is reflected in vertical technique. This pops up in various places on a lot of different forums, but perhaps it would be useful to assemble our collective wisdom on the matter into one thread. To get the ball rolling, here are a few thoughts:
- Long ascents:
Cavers often work over much longer vertical distances than tree climbers. Even a coastal redwood is not that big a climb to a serious vertical caver. A caver then has much more concern with energy efficiency during climbs than most tree climbers do. A Mitchell ropewalker is a more or less standard system among cavers, but is something of an outlier among tree climbers (I happen to like it, partly 'cause I'm out of shape). DdRT and SRT systems like the Texas (jugging) and the yoyo (or RADS) are not as energy efficient, but they are gear efficient and flexible - both higher priorities for tree climbers. Also, the climbing environment of tree climbers is usually much more spatially complex (winding around branches vs. you, the rope, and the cliff...), so simple flexible systems are really nice.
- Long descents/rappels:
Cavers and rock climbers often rappel for much longer drops than even big tree climbers. At the top of a long rapp, that's a lot of rope weight, and the weight will be decreasing to nearly zero during the rappel. For this reason, variable friction devices like racks are favored because they allow lots of options for gradually changing the friction during the drop. Racks are also about the best at dissipating the heat of a long drop. Rappelling out of a tree is generally a lot less exacting; variable friction is not a big issue because the rope weight at the top is not so great (except in big trees, and even then not nearly so much as above a really deep pit), and heat dissipation is a lot less critical than when going off, say, Half Dome in Yosemite. We use a lot of devices, and there is plenty of room for personal preference.
Another issue is the use of rappel safety knots. They are frowned upon in many caving circles for a couple of reasons: a) they depend on taking your hands OFF to stop (not a natural reaction for most people), and b) the safest configuration (knot below the rappel device, so that the device takes most of the stress in a panic stop) precludes many of the options for varying the friction in the middle of a rappel. As noted above, the second issue is not a big one for tree climbers. The first issue (let go to stop) is potentially serious, but for anyone trained on DdRT, letting go to stop is very well established in the muscle memory and comes quite naturally.
- Ropes:
Of course, not too many tree climbers use the dynamic (springy) ropes that rock climbers favor, because they seldom if ever climb above their tie-in points. A really springy rope would waste a lot of energy during a climb, but a bit of spring is nice to soften the little falls that sometimes happen when going from branch to branch.
- Carabiners:
Tree climbers re-rig a lot during a climb; carabiners come on and off quite often - on average probably a lot more than for rock climbers and cavers. That's probably why tree climbers often (but not universally) prefer autolocking 'biners, and rock climbers always give them weird looks.
- Saddles:
Tree climbers spend lots of time hanging in their saddles, which is why so many of us are grateful to New Tribe (and the manufacturers who have learned from New Tribe) for making saddles in which it is comfortable and safe to hang out. For cavers and rock climbers, a harness is something to hang in as little as possible while you are on your way to somewhere else, or something to catch you in a fall. I've never heard of anyone getting \"harness hang syndrome\" (a very dangerous condition of reduced blood circulation caused by narrow harnesses) in a well-designed tree climbing saddle, but it's a nasty problem for someone sitting in a rock climbing harness for long.
- Tie-ins:
The mechanics and technology of tie-ins are of course rather different for rocks vs. tree branches. Beyond that, tree climbers sometimes change tie-ins as often as rock climbers doing a lead climb. One option rock climbers DON'T have, of course, is setting a TIP 30-130 feet overhead - and this raises some different safety issues when you have to assess TIP safety from a distance...
Can't think of anything else for now. I'll leave aside the differences in attitude, taking it for granted that we all know how much nicer tree climbers are.
Anything to add? Any controversy?