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How Arborists Work


Arborist Certification
The International Society of Arborists certifies professional arborists in several levels of professional skills.
The International Society of Arborists certifies professional arborists in several levels of professional skills.
Reza Estakhrian/­Getty Images

­If you thought taking care of trees was a simple, straightforward job, think again. Anyone who wants to become an arborist must spend a great deal of time studying, preparing and getting experience in the world of trees, and becoming a licensed professional can take years of hard work. Arborists will typically study at any number of two- or four-year college programs, getting a degree in arboriculture, horticulture or a combination of the two studies.

After joining any number of arborist associations, including the Tree Care Industry of America (TCIA) and the American Society of Consulting Arborists (ASCA), the main goal is to get certification from the International Society of Arboriculture (ISA). There are essentially five different licenses an arborist can acquire from the ISA along his or her career path. Before receiving each one, arborists must take an exam that tests their knowledge, abilities and experience. The largest group of licensed arborists is the Certified Arborist, the first certification an arborist can receive. These credential holders generally have basic knowledge of tree science and basic skill in tree care. ISA Certified Arborists must have at least three years of experience before they take the exam, which covers all areas of arboriculture.

Within this group, however, arborists can take another test to receive a second, more specialized certification: the Certified Tree Worker, which designates the arborist as a climber specialist. An arborist who wants to become a Certified Tree Worker needs to have at least 18 months of professional tree climbing and should have the necessary skills, including pruning, tree removal, cabling and safety. The exam is both written and skill-based, the latter of which is conducted by skilled evaluators.

Above the Certified Arborist are two positions: the Utility Specialist and the Municipal Specialist. Utility Specialists have the specific job of caring for trees around power lines. Any time there's a fallen tree near dangerous electrical equipment, a Utility Specialist must be able to safely remove any potentially hazardous branches from the scene. A Municipal Specialist, on the other hand, works more broadly in urban areas, working in city and state parks often alongside contractors and consultants.

The highest certification an arborist can achieve is ISA Board-certified Master Arborist, meant for experts in the field of arboriculture with years of professionalism in tree care. The Board-certified Master Arborist must meet a list of specific prerequisites that cover experience and education and also complete a 150 question exam developed by industry experts. The number of Board-certified Master Arborists around the world should tell you how challenging the certification is -- there are only 120 Board-certified Master Arborists internationally [source: Autumn Tree Care Experts].

For lots more information on trees and tree care, see the links on the next page.