International Society of Arboriclture
An arborist is a specialist in the care of individual trees. Arborists are knowledgeable about the needs of trees and are trained and equipped to provide proper care. Hiring an arborist is a decision that should not be taken lightly. Proper tree care is an investment that can lead to substantial returns. Well-cared-for trees are attractive and can add considerable value to your property. Poorly maintained trees can be a significant liability. Pruning or removing trees, especially large trees, can be dangerous work. Tree work should be done only by those trained and equipped to work safely in trees.
Service that Arborists Can Provide
An arborist can determine the type of pruning necessary to maintain or improve the health, appearance, and safety of trees. These techniques include:
- eliminating branches that rub each other
- removing limbs that interfere with wires, building facades, gutters, roofs, chimneys, or windows, or that obstruct streets or sidewalks
- removing dead or weak limbs that pose a hazard or may lead to decay
- removing diseased or insect-infested limbs
- creating better structure to lessen wind resistance and reduce the potential for storm damage
- training young trees
- removing limbs damaged by adverse weather conditions
- removing branches, or thinning, to increase light penetration
- improving the shape or silhouette of the tree
Although tree removal is a last resort, there are circumstances when it is necessary. An arborist can help decide whether a tree should be removed. Arborists have the skills and equipment to safely and efficiently remove trees. Removal is recommended when the tree:
- is dead or dying
- is considered irreparably hazardous
- is causing an obstruction that is impossible to correct through pruning
- is crowding and causing harm to other trees
- is to be replaced by a more suitable specimen
- is located in an area where new construction requires removal
Storms may cause limbs or entire trees to fall, often landing on other trees, homes and other structures, or cars. The weight of storm-damaged trees is great, and they can be dangerous to remove or trim. An arborist can assist in performing the job in a safe manner, while reducing further risk of damage to property.
Many arborists also provide a variety of other tree care services, including Plant Health Care (PHC). This concept of preventive maintenance keeps trees in good health, which will help the tree better defend itself against insects, disease, and site problems.
- cabling or bracing for added support to branches with weak attachment
- aeration to improve root growth
- installation of lightning protection systems
- spraying or injecting to control certain insect and disease problems.
Selecting the Right Arborist for the Job
When selecting an arborist:
- Check for membership in professional organizations such as the International Society of Arboriculture (ISA), the Tree Care Industry Association (TCIA), or the American Society of Consulting Arborists (ASCA).
- Check for ISA arborist certification.
- Ask for proof of insurance and then phone the insurance company if you are not satisfied. A reputable arborist carries personal and property damage insurance as well as workers compensation insurance.
- Check for necessary permits and licenses. Some governmental agencies require contractors to apply for permits and/or to apply for a license before they are able to work.
- Ask for references to find out where the company has done work similar to the work you are requesting.
- Get more than one estimate, unless you know and are comfortable with the arborist. You may have to pay for the estimates, and it will take more time, but it will be worth the investment.
- Don’t always accept the low bid. You should examine the credentials and the written specifications of the firms that submitted bids and determine the best combination of price, work to be done, skill, and professionalism to protect your substantial investment.
- Be wary of individuals who go door to door and offer bargains for performing tree work. Most reputable companies are too busy to solicit work in this manner. Improper tree care can take many years to correct itself and, in some cases, it can never be corrected. Are you willing to take that risk with your valuable investment?
- Keep in mind that good arborists will perform only accepted practices.
- Get it in writing. Most reputable arborists have their clients sign a contract. Be sure to read the contract carefully. Don’t be afraid to ask questions, such as:
When will the work be started and completed?
Who will be responsible for clean-up?
Is this the total price?
If I would like more to be done, what is your hourly rate?
Be an informed Consumer!
One of the best methods to use in choosing an arborist is to educate yourself on some of the basic principles of tree care. ISA offers several other brochures in this series, which discuss many of the basic principles of tree care. Your local garden center, extension agent, or city arborists are also excellent sources of information if you should have further questions. They may also be able to refer you to an ISA Certified Arborist in your area.