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

    Lichen 101 for Arborists


    How’s your ability to distinguish lichens that grow on tree trunks and branches from mosses and algae? A lichen is a mutualistic symbiotic relationship composed of two or more organisms (from up to three entirely different Kingdoms!). A mycobiont (fungus) makes up the majority of the “body” (thallus) of the lichen, while the photobiont (algae or photosynthetic bacteria, or both) typically resides inside the lichen’s thallus. Together, as a lichen, these organisms are able to live in environments where, individually, they would be unable to survive. Lichens play important roles in every terrestrial ecosystem on earth, including the urban ecosystem. With a brief biology lesson on lichen, you can change your client’s (and the public’s) skeptical disposition to one of understanding, acceptance, and even appreciation. But first, we need to educate the arborist. This presentation will explain the who, what, where, when and why of common lichens that grow on tree trunks and branches. 



    Conference Proceedings Documents


    Joe’s educational background includes the completion of a Masters of Science in Plant Pathology from Virginia Tech, Masters in Teaching from the University of Richmond, and a Bachelor of Arts in Biology from Radford University. Joe is an ISA certified arborist, certified utility arborist, certified tree worker/climber specialist, and tree risk assessment qualified. Joe, a former college biology professor, is a trainer for the Mid-Atlantic Chapter of the International Society of Arboriculture and an independent consulting arborist. When Joe is not hiking or participating in research projects along the Appalachian Trail in the Blue Ridge Mountains, he morphs into a tree biology educator, traveling around the United States teaching and learning about trees and people.


    Climbers' CornerTree Academy

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