Evergreen Arborist
What is a Certified Arborist or Tree
Risk Assessor?
March, 2009
The simple answer is that we are a form of "tree doctors". But it goes much further than that.
Anyone can call themselves an "arborist". But only those that have completed certification processes can earn the professional designations of "Certified Arborist" or "Certified Tree Risk Assessor".
The International Society of Arboriculture (ISA) requires passage of a comprehensive examination on the art and science of tree care, at least three years of practical experience, membership in a professional organization such as the ISA and participation in continuing education programs to earn the "Certified" designations.
The Pacific Northwest Chapter of the ISA recently developed a new important designation of "Certified Tree Risk Assessor". This requires additional special training and passage of a comprehensive examination on the assessment of hazardous trees.
Certification measures the tree knowledge of an individual, but it cannot guarantee quality performance of work. Before employing a certified arborist, a potential consumer should ask questions, check references and, for those that offer various tree services, be certain they are bonded or otherwise properly insured.
Services Are Varied
Many certified arborists are self-employed individuals that perform all their own services. Others offer expanded tree care and landscape services. Public agencies also have employees that have attained the designation.
Many offer pruning services. Certification not only means that an arborist will use the proper techniques for tree care, but that he/she also knows what not to do to improve the health, safety and appearance of trees and shrubs.
Tree removal is a big business. The primary goal of certified arborists is to recommend tree removal as a last resort. They are trained to use their best judgement, experience and tools to evaluate the health and safety of trees and make appropriate recommendations. While it is impossible to predict if or when a branch or an entire tree failure will occur, an arborist can point out the possibilities of which to be aware.
Damage appraisals may be called for under various circumstances. Certified arborists use widely recognized tree formulas to estimate the value of trees. For large landscape trees, values can easily reach several thousands of dollars.
Many offer legal services beyond damage assessments. These may include expert witness testimonies at depositions and trials.
Most offer a wide range of consulting services to homeowners, local governments, developers and other entities involved in tree care. Several communities and homeowner associations that have tree preservation ordinances will require a report from a certified arborist when a homeowner expresses concerns about protected trees.
Be Suspicious
Beware of the tree "expert" or "arborist" or "arborist in training" that knocks on you door and proclaims that a tree looks sick and must be removed or have some type of treatment to make it safer. Such an individual can claim to be an "arborist" but is not certified. Sometimes these are salespersons paid on commission. Their certification can be verified by checking one of the sources noted below.
Often it is prudent to seek a second opinion. I have been called in on some situations and have usually recommended something other than what the unsolicited doorbell ringer was suggesting.
Sources for Certified Arborists
The yellow pages under "Tree Services" list a few arborists or state that a tree service has such on their staffs.
"DEX Knows.com" and searching for "Certified Arborists" on the Internet will reveal lists from various areas. Search for "PNW-ISA" ( Pacific Northwest Chapter of the ISA) and follow the links to a list of certified members in British Columbia, Oregon and Washington.
Those of us that have earned the designations take great pride in them. While we feel we can offer quality and conscientious services, we also believe that we have an important role to help educate the public about proper tree care.