Speakers: John Ball of South Dakota State University

Friday, November 28, 2008
Canopy Loading in Trees – Dr. John Ball

  •     How Trees Dampen Movement
  •     Dynamic Loading in Trees

Static Loading in Trees

Load Reduction – Dr. John Ball

  •     Pruning Classification
  •     Influence of Pruning on Tree Vitality
  •     Value of Pruning in Load Reduction and Redistribution
  • Rigging Forces

Demonstration of Cobra Support Installation

Field Activities
(View Trees in New Territories for Discussion)
John Ball & Don Picker

Saturday, November 29, 2008
Load Support – Dr. John Ball

  • Tree Support Systems
    • Load Distribution With Support Systems
    • Traditional Versus Alterative Systems

Introduction of Materials for Tree Support Systems
Tree Assessment and Response to Loads – Dr. John Ball

  • Common tree failure points:
  • Tree Evaluation
  • Site
  • Defects
    • Roots
    • Trunk
    • Canopy

Mitigation of Risk

Tree Assessment Practice in Hong Kong & Reports
(Don Picker of ATP, Ltd. provides an example of hazard tree
assessment locally on Bonham Road, Hong Kong)
Introduce assessment alternatives – Don Picker
Demonstration of Air Spade by Don Picker

Demonstration of Air Spade by Don Picker

Field Activities

John Ball & Don Picker
Practice application of the English/Chinese form for Visual Tree Assessment (VTA)
(Viewing and close investigation of trees in the surrounding area to discuss and practice
tree assessment and mitigation or options for action to deal with problems in potentially
hazardous trees. Use of shigometer, increment borer, etc…)
View tree on campus that have been damaged by work done to construct a drain canal and
some have experienced problems by other applications of construction.