This is an explanation taken from the International Society of Arborist webpage. “The Certified Arborist credential identifies professional arborists who have a minimum of three years’ full-time experience working in the professional tree care industry and who have passed an examination covering basic facets of arboriculture”.
A lot of times, clients have had certified arborists come to the site and inspect the tree, but the clients were severely disappointed in the level of knowledge and professionalism they experienced. Just because someone holds the credential does not mean they are fully qualified to diagnose and answer certain issues pertaining to the biology and risk of trees. The ISA explains that the credential holder has shown the minimum requirements for general tree care and it’s mostly geared towards tree trimming and not specialized maintenance practices or diagnostic techniques. Most certified arborists are tree trimmers that received a credential to show they were qualified for general tree care. Too many times, we’ve experienced business owners or salesmen who got the certification just for what they thought would lead to an income increase or a better sales tactic. We only say this to highlight and explain the importance of validating the authority from which you are receiving an opinion and information.