TREE Fund

Tree Research & Education Endowment Fund

2009 Grant Research Archive Research Fellowship 

Assessing the impact of decay on the structural integrity of trees

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2009 | Dr. Brian Kane, University of Massachusetts, Amherst

Arborists have performed tree risk assessments for many years. Over time, the process has become increasingly detailed, and arborists and urban foresters have better tools to detect decay. However, there is a real gap in how we understand the severity of defects and at what point defects should be considered too severe. As a result, arborists and urban foresters continue to rely heavily on their experience when assessing tree risk. Probably the best example of this is the development of high-tech tools to measure decay, without knowing how much decay is too much and makes the tree unsafe.  Our plan is to break trees with and without decay and measure their strength. We will then use engineering computer software to try to predict when decay is so severe that action must be taken (removal or pruning, etc.). We hope that this project will provide good scientific data to better understand how strong trees are and what kinds of forces and stresses they can withstand.

Study Results

Three improvements to tree risk assessment are noteworthy: including the effects of dynamic loading and response of trees, accounting for variations in wood properties of trees and off-center areas of decay and using probabilistic methods to predict likelihood of failure for trees with and without decay and leaves. One limitation of the work is that only two species (Acer saccharum, Quercus rubra) were included in the empirical tests. For many aspects of the modeling work, however, the results can be comparatively easily applied to other species once their empirical parameters are measured.

Our findings will significantly improve the way practitioners assess risk in trees, which is an immediate and positive impact of the work. In the long-term, the benefit of our work is much broader. We hope that our work will raise awareness of arboricultural research among scientists in other disciplines (related or unrelated to arboriculture and urban forestry).

Year: 2009

Funding Duration: 3-5 years

Grant Program: Research Fellowship

Grant Title: Assessing the impact of decay on the structural integrity of trees

Researcher: Brian Kane

Key words: Co-dominant stem  Decay  Decurrent  Tree failure  Tree pulling

Peer Reviewed Publications from Grant:

  • Kane, B. Determining parameters related to the likelihood of failure of red oak (Quercus rubra L.) from winching tests. In Press. Trees:  Structure & Function.
  • Ciftci, C., S.R. Arwade, B. Kane, and S. Brena. 2014. Analysis of the probability of failure for open-grown trees during wind storms. Probabilistic Engineering Mechanics 37:41-50.
  • Ciftci, C., B. Kane, S. Brena, and S.R. Arwade. 2014. Moment capacity loss due to decay in tree stems. Trees:  Structure & Function 28:517-529.
  • Ciftci, C., S. Brena, B. Kane, and S.R. Arwade. 2013. The effect of crown architecture on dynamic amplification factor of an open-grown sugar maple (Acer saccharum L.). Trees:  Structure & Function 27:1175-1189.

General Audience/Trade Publications: none

Presentations:

  • Breaking Large, Open-grown Trees. UConn graduate seminar, Storrs, CT, March 2014 [20 attendees].
  • The Biomechanics of Tree Risk Assessment (2 hrs.). Idaho Nursery and Landscape Association, Boise, ID, January 2014 [100 attendees].
  • Tree Biomechanics Workshop (full day). Centre for Urban Greening and Ecology Special Seminar, Singapore, July 2013 [50 attendees].
  • Tree Biomechanics. CTPA Annual Meeting, Plantsville, CT, January 2013 [850 attendees].
  • Tree Biomechanics Workshop (full day). Centre for Urban Greening and Ecology Special Seminar, Singapore, March 2012 [80 attendees].
  • Tree Biomechanics Workshop (full day). Melbourne, Australia, March 2012 [75 attendees].
  • Ciftci, C., S. Brena, B. Kane, and S.R. Arwade. 2014. A probabilistic approach to tree risk assessment. European Arboriculture Congress, Torino, Italy May 2014 [300 attendees].
  • Ciftci, C., S. Brena, B. Kane, and S.R. Arwade. 2013. The effect of crown architecture on dynamic amplification factor of an open-grown sugar maple (Acer saccharum L.). Annual Conference, Uncasville, CT December 2013 [310 attendees]
  • Ciftci, C., B. Kane, S. Brena, and S.R. Arwade. Moment capacity loss due to decay in tree stems. ASCA Annual Conference, Uncasville, CT December 2013 [310 attendees]
  • Cifti, C., S. Brena, B. Kane, and S.R. Arwade. 2012. Effects of crown architecture on dynamic behavior of trees. ISA Annual Conference, Portland, OR August 2012 [150 attendees].

For more information on this project, contact the researcher via TREE Fund at treefund@treefund.org.