All types of climbing requires all types of anchors. One commonly used anchor in top-roped climbing as well as in multi-pitch climbing is the ubiquitous tree. Trees and bushes are everywhere. You can find solid trees sticking out of cracks in the middle of a route and you can find weak trees sitting on top of a crag. As a result it is very important to look carefully at a tree before using it.
In traditional anchors, we often use the acronym SERENE to determine whether an anchor is good or not. The letters in SERENE stand for the following:
S -- Solid -- Are all the pieces in the anchor solid?
E -- Equalized -- Are all the pieces equalized?
R -- Redundant -- Is there redundancy throughout the sysytem?
E -- Effective -- Was the anchor construction simple and quick with no fuss?
NE -- No Extension -- Will the system be shock-loaded if a piece blows?
All anchors should pass the SERENE test or come extremely close to passing this test.
When we find a big fat tree that we elect to use as an anchor, the tree generally will not pass this test. Why? Because a single tree is not redundant. However, if the tree is giant and has a good root-base, redundancy doesn't matter as much. All the other letters in the acronym will be satisfied.
The SERENE acronym becomes significantly more important when the tree or bush that you wish to use in your anchor isn't very good. Occasionally, we have to link together a series of shrubs in order to create a SERENE anchor. It's important to use as many as you need to use in order to make the anchor as strong as it needs to be.
Following is a video about what to look for in a good tree anchor:
--Jason D. Martin
