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

Order Delays Due to Physical Inventory

Due to ISA's annual physical inventory, orders placed between
2 p.m. EDT, Thursday, 20 June 2019, and 11:59 p.m. EDT, Friday 28 June 2019, will not ship until the week of 1 July 2019

Please plan your ordering accordingly.

We will resume regular turnaround times
1 July 2019.

Thank your for your patience.

Questions? Please call the customer service team at (678) 367-0981.

    Climbers' CornerTree Academy

    The Double-System Technique (DST): Working in Trees with Redundant Safety


    How can tree climbing be even safer?  If we back up every piece of positioning equipment and add a secondary climbing line, can we eliminate the possibility of falling out of the tree?  Does the Double-System Technique save time, money, and injury?

    This Climber’s Corner demonstration will explore the concept, practice, and gear necessary to perform tree work with a fully redundant climbing system.  This will include an ascent and working strategy for both deciduous and conifer trees.  Troubleshooting, gear pricing, and system improvement will be discussed as part of the DST evolution.



    Nicholas Whittaker Dankers is a graduate student at the University of Washington.  With 11-years as a tree climber and 22-years as a mountaineer, he has used this arboricultural experience to develop a simplified, redundant climbing system where any piece can fail without catastrophic results.  After presenting at the Portland and Toronto conferences, he has refined the Double-System Technique to a functional, safe practice.

    Climbers' CornerTree Academy

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