Static Integrated Method - Pull Test

Leon and all,

This method of assessing tree stability and trunk strength is fascinating and is proving to be a very valuabe tool for Arborists making decisions about tree retention and management.

My office has completed three tests with help from Phillip vanWassanauer (Ontario) and Erk Brudi and his office in Germany. The results were very useful to us and to our clients.

The PNWISA conference in Redmond this month will feature an all day workshop with two German tree scientists engineer Andreas Detter and biologist Michael Schlag will be presenting.

My hope is that the method will allow testing of tall conifers for stability...currently a difficult call fo most of us....and one that often results in trees removed IMO too soon or for no real reason (other than fear).

In a nutshell the test invloves modeling wind loads on the subject tree and then pulling on the tree with a portion of the max load and measuring the inclination of the tree base and elongation of the trunk wood fiber with sensative instruments.

Its a non invasive process and although it is complex...its only math. Here are two links to more reading.

http://www.treeworks.co.uk/downloads/2%20-%20JK_Static%20Integrated%20031203.pdf#search=%22statics%20integrated%20method%22

http://www.tree-consult.org/images/pdf/eng/brudi_trees_and_statics.pdf#search=%22trees%20and%20statics%22

What do you all think? Scott

Is this the method that uses a tractor to provide pull? I have not read the links yet- I confess.

Using trucks or tractors to pull trees has been done by many people thatr i hae heard about howeverit is a very rough method.
The SIA method uses a cable winch called a griphoist. Its cool because you can add load very slowly and also back off slowly toohile watching the load on a dynamometer.

Thanks for the post and links, Scott. I saw this demonstrated at the ISA conference in Nashville and was really intrigued. It is the only process that I have seen so far that can test the ACTUAL strength of a tree (especially root failure) as opposed to theoretical strength derived from mathematical formulas.

Trees are often much stronger than they appear to be and this method offers the opportunity to save many trees which might otherwise be cut down out of uninformed fear.

A few days ago I read the links you added scott. Very intriguing.

How do they determine where to tie the rope that you pull on? How high up do you go?

love
nick