Contact Us

Email us
Phone: +1.678.367.0981
Fax: +1.240.547.1795

Mailing Address

International Society of Arboriculture
PO Box 191
Annapolis Junction, MD 20701
United States

Physical Address

International Society of Arboriculture
270 Peachtree St NW, Suite 1900
Atlanta, GA 30303
United States

0

    Climbers' Corner • Tree Academy
    Monday • Tuesday • Wednesday

    Assessing the Potential of Reduction Pruning in Mitigating the Risk of Branch Failure

    Summary

    The failure of branches during periods of severe weather poses risks to public safety, services, and infrastructure.  The traditional approach to mitigating risks to critical targets such as utility lines has been to attempt the removal of branches that overhang conductors.  However these branches are often difficult to access and expensive to remove.  As a result, “ground-to-sky” line clearance pruning is rarely practical or achievable, and generally occurs only on the most critical line segments where an interruption in service will result in an outage affecting a large number of customers.  Excessive removal of branches may also adversely affect the health of trees.
     
    Earlier work by the researchers identified the potential of branch reduction pruning to be an effective means of reducing the risk of branch failure. Work completed during ISA Tree Biomechanics Week 2010 resulted in the development of an experimental protocol suitable for investigating the efficacy of branch reduction pruning as a means of reducing risk of branch failure.  This work was subsequently completed in 2012.
     
    This paper will present the results of the 2012 research that quantifies the relationship between pruning dose, reductions in bending moment and fiber strain in the critical fracture zone of a branch.  The results demonstrate that branch reduction pruning can be an effective alternative to the total elimination of branches at risk of failure.  An investigation of the fundamental sequence of failure mechanisms that occur as a branch is loaded to the point of fracture will be completed in 2013.  That project is being undertaken in cooperation with the NASA John Glenn Research Center, and should be completed in time to include a discussion of summary findings in this presentation.
     

    Conference Proceedings Documents

    Presenters

    John Goodfellow and Andreas Detter have been collaborating on biomechanical research focusing on branch failure mechanisms since 2009.  Their earlier work resulted in the development of risk assessment criteria for branch failure within the crowns of trees, and was presented at ISA’s 2010 Annual Conference in Chicago.  The team completed this project in 2012 and has plans for further work in 2013, in cooperation with the NASA John Glenn Research Center.

    Mr. Goodfellow has 30 years of experience in the electric utility industry, having held positions of responsibility for vegetation management at three large investor-owned electric and gas utilities.  He is recognized as a leading authority on utility vegetation management and reliability.  Mr. Detter holds an engineering degree in landscape design and teaches at the University of Applied Sciences in Weihenstephan, Germany.

    Climbers' Corner • Tree Academy
    Monday • Tuesday • Wednesday

    True True True