Climbers' Corner • Tree Academy
Monday • Tuesday • Wednesday
Does Taper Affect Bending Stress at the Base of Branches?
Summary
As wind, snow, or ice builds up
along branches, bending moments are created that increase proximally towards
the branch base. Theoretically, maximum bending stress should be at the point
of attachment, yet arborists report that storm damage often occurs near the base,
rather than at the point of attachment. This reported failure pattern could be the
result of branch taper, which may shift the maximum stress location distally
beyond the point of attachment. This presentation will discuss a study that
measures taper along a series of branches and then applies theoretical loading to
the branches. Bending stress will be calculated at fixed locations along the
proximal end of branches to predict where maximum stress occurs. This
information may be useful to practitioner in understanding where branches fail,
and to modelers when building tree failure models.
Conference Proceedings Documents
Presenters
Dr. Gregory Dahle is developing the arboriculture and urban forestry
program in the Division of Forestry & Natural Resources at West Virginia
University. He holds a doctorate from Rutgers University, a Master and
Bachelor of Science from Purdue University, and is an ISA Board-Certified
Master Arborist. Dr. Dahle’s research utilizes allometric modeling and tree
biomechanics to understand how urban trees grow and survive environmental loads
such as those from snow and ice storms. He has worked as an arborist managing
commercial and municipal tree care accounts in the San Francisco Bay Area and
served as a consulting utility arborist with the Davey Resource Group
throughout northern California. Additionally, he worked with the Bartlett Tree
Research Laboratory.
Climbers' Corner • Tree Academy
Monday • Tuesday • Wednesday