Modern Arboriculture by Dr. Alex Shigo
Details
Dr. Alex Shigo gives a thorough course on tree health, biology, and proper pruning and management. Very in-depth science and love of trees have gone into this book, making it a great resource.
423 pages, hardbound.
Dr. Alex Shigo has been called “the Father of Modern Arboriculture” for his ground-breaking research and new ideas he has formed about trees. Shigo graduated with a masters in biology and a Ph.D. in pathology, then went to work for the Forest Service. That was the beginning of a career that has spanned more than 40 years and has vastly enriched our modern knowledge of how trees live and die, and how tree care professionals can improve their efforts in the care of trees. Dr. Alex Shigo's contributions in the world of arboriculture will last for generations.
Why This Book Is Helpful for Arborists
Modern Arboriculture by Dr. Alex Shigo remains a foundational resource for arborists due to its lasting impact and transformative influence on tree care practices.
Revolutionizing Tree Care Standards
Shigo’s research introduced the concept of CODIT (Compartmentalization of Decay in Trees), proving that trees seal wounds rather than heal them. This led to widespread adoption of target pruning and the three-cut method, replacing flush cutting and reducing internal decay. His insights now inform standards like ANSI A300, improving long-term tree health and safety.
Dispelling Harmful Myths
Shigo debunked outdated practices such as wound dressings, topping, and cavity filling, showing they often cause more harm than good. His evidence-based critiques helped shift the industry toward more tree-friendly care.
Scientific Foundation for Practice
The book offers a rich, accessible explanation of tree physiology, helping arborists understand how trees grow, defend, and decline. This knowledge informs better diagnosis and decision-making, transitioning arboriculture from tradition-based work to science-driven professionalism.
Influence on Arborist Education
Modern Arboriculture is widely used in certification programs and university courses. Its concepts—CODIT, proper pruning, root care—are standard in ISA exams and study guides. Many arborists keep the book as a field reference.
Impact on Urban Forestry
Shigo promoted a systems approach: focusing on soil health, structural pruning, and long-term resilience. His work guides arborists to treat root causes, not just symptoms, leading to healthier trees and more sustainable urban forests.
Professional Mindset and Ethics
Shigo encouraged arborists to respect trees as living systems—“Touch trees,” he said. His philosophy fostered curiosity, empathy, and a lifelong commitment to learning, raising the ethical standard of the profession. The book is still seen as an essential guide decades after publication.