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International Society of Arboriculture
270 Peachtree Street NW
Suite 1900
Atlanta, GA 30303
United States

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International Society of Arboriculture
PO Box 191
Annapolis Junction, MD 20701
United States

Events
EventsAnnual Conference2024 Annual Conference

ISA 2024 Annual International Conference in Atlanta, GA

The International Society of Arboriculture (ISA) will celebrate 100 years of professionalism this year. Looking back over the years, seeing how the organization grew is exciting. In 1924, the first Shade Tree Conference was held in Stamford, Connecticut, and opened with about 36 participants from several different states. Today, our most recent Annual International Conference had approximately 905 attendees from 23 other countries. In 1974, the first official Tree Trimmer's Jamboree was held and featured a 40-ft. foot lock and a work climb consisting of three workstations. Now, the International Tree Climbing Championship features five different events and the best climbers around the globe. In 1992, the ISA Certified Arborist® program launched, which not only brought greater recognition for the profession but led to the creation of several other more specialized credentials and qualifications as well.

ISA has grown tremendously over the past 100 years, and our impact on the profession and the community continues to grow in ways that the first Shade Tree Convention participants may not have imagined. We want to thank our members and credential holders who've taken this incredible journey with us as we celebrate our accomplishments. Your support has brought us to this milestone.

In August 2023, ISA began its Road to Centennial Celebration, a year-long series of events and initiatives. This includes, among other things, articles in Arborist News highlighting the organization’s history, special webinars with industry leaders, and a commemorative book. We encourage everyone to join us as we celebrate 100 years of professionalism and promote the professional practice of arboriculture. The road to Centennial culminates at the 2024 Annual International Conference, 12 – 14 August, in Atlanta, Georgia, where we will have a grand celebration and honor the contributions of our members and credential holders. We hope to see you there.

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Learn More About the History of ISA

April Centennial Trivia

Arborist News Articles

As we celebrate our Annual Conference, marking a century of progress and achievement, these member-access only articles offer a unique glimpse into our rich history, pivotal moments, and the extraordinary individuals who have propelled us forward.

  • 100 Years of Service by Sharon Lilly - This article is the first in a year-long series to celebrate ISA's 100th anniversary. Each article in the series will highlight certain aspects of ISA's history. The International Society of Arboriculture and the profession of arboriculture share a rich history. Although arboriculture can trace its roots back thousands of years, its development as a profession parallels the emergence and growth of ISA
  • A Centurion Story of Arboriculture and Urban Forestry through Dutch Elm Disease by Richard J. Hauer - Tree care has advanced in many ways over the last century. Science and practitioner ingenuity have led to better techniques with tree pruning, tree risk assessment, tree support systems, soil management, tree planting, pest management, and many other approaches. The story of Dutch elm disease (DED) highlights more than 100 years of this collective advancement. The DED account illustrates how technology and science helped overcome one of the original three-letter tree killers. 
  • Celebrating a Centry of Internationalization, Chapters, and Governance by Rose Epperson - As the International Society of Arboriculture celebrates its centennial anniversary, it is time to reflect on the organization's remarkable journey and the significant milestones achieved in the fields of arboriculture and urban forestry. Over the past century, ISA has played a pivotal role in promoting the global exchange of knowledge, establishing local chapters, and fostering effective governance structures. This article aims to highlight the remarkable achievements of ISA in internationalization, the establishment of chapters, and the development of effective governance, which have contributed to its success and impact worldwide. 
  • Accident Prevention Then and Now by John Ball
  • A Leader in Arboriculture Education by Sharon Lilly - For the first half of its 100-year history, ISA was almost entirely an annual conference. Indeed, the organization was originally named the Shade Tree Conference, then the National Shade Tree Conferece, and later the International Shade Tree Confererence, before becoming the International Society of Arboriculture in 1976. The International Society of Arboriculture began as a marriage of convenience between progressive commercial arborists and scientists whose research concerned trees. Although tree care had been practiced by commercial companies and individuals for years, the industry was largely unregulated and uninformed. As for the scientists, their knowledge of amenity trees and tree care was somewhat limited. There were many demanding questions in horticulture, forestry, entomology, and plant pathology concerning trees - questions that required research for answers - but not much funding to do it. 
  • Back to the Future, Reflections on Dr. Clyde Hamilton's 1954 History of Shade Tree Insect Control and His Predictions for the Future by Daniel A. Herms
  • The ISA Credentialing Program, A Story of Growth and Expansion by Sharon Lilly
  • Looking Back Can Help Us Manage the Future by Greg Dahle and Agatha Dahle
  • The History of TCCs