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
Removal
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
Emergency Tree Care
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.
Planting
Some arborists plant trees, and most
can recommend types of trees that are appropriate for a specific
location. The wrong tree in the wrong location could lead to
future problems as a result of limited growing space, insects,
diseases, or poor growth.
Other Services
Many arborists also provide a variety
of other tree care services, including
- Plant Health Care, a concept of preventive
maintenance to keep trees in good health, which will help the
tree better defend itself against insects, disease, and site
problems
- fertilization
- 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). Such membership
demonstrates a willingness on the part of the arborist to stay
up to date on the latest techniques and information.
- check for ISA arborist certification. Certified
Arborists are experienced professionals who have passed an
extensive examination covering all aspects of tree care.
- 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. Many home owners have had to pay
out large amounts of money for damages caused by uninsured
individuals claiming to be tree experts. You could be held
responsible for damages and injuries that occur as a result of
the job.
- 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. Be
sure they comply with any local, state, provincial, or national
laws that govern their work.
- ask for references to find out where the
company has done work similar to the work you are requesting.
Don’t hesitate to check references or visit other work sites
where the company or individual has done tree work. Remember,
tree care is a substantial, long-lasting investment; you would
not buy a car without a test drive!
- 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. For example, practices such as topping
a tree, removing an excessive amount of live wood, using
climbing spikes on trees that are not being removed, and
removing or disfiguring living trees without just cause are
unnecessary.
- 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?
What Is a Certified Arborist?
An arborist by definition is an
individual who is trained in the art and science of planting,
caring for, and maintaining individual trees. ISA arborist
certification is a nongovernmental, voluntary process by which
individuals can document their base of knowledge. It operates
without mandate of law and is an internal, self-regulating device
administered by the International Society of Arboriculture.
Certification provides a measurable assessment of an individual’s
knowledge and competence required to provide proper tree care.
Certification is not a measure of
standards of practice. Certification can attest to the tree
knowledge of an individual but cannot guarantee or ensure quality
performance.
Certified Arborists are individuals who
have achieved a level of knowledge in the art and science of tree
care through experience and by passing a comprehensive examination
developed by some of the nation’s leading experts on tree care.
Certified Arborists must also continue their education to maintain
their certification. Therefore, they are more likely to be up to
date on the latest techniques in arboriculture.
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.
This brochure is one in a series
published by the International Society of Arboriculture as part of
its Consumer Information Program. You may have additional interest
in the following titles currently in the series:
