How to Hire an Arborist

Many important tree care practices such as pruning, watering, mulching, and fertilizing of young trees can be accomplished by the homeowner. However, as trees become older and larger, some these tasks, especially pruning, become more difficult and potentially dangerous. Professional arborists are available to assist homeowners with the proper care of their trees from the be-ginning of the trees life to the time they must be removed from the landscape.

Arborists are persons that specialize in the management and care of individual trees. A professional arborist is knowledgeable about tree care and usually has formally studied in the area of arboriculture, forestry, or horticulture, and/or has had extensive training in the area of arboriculture through work-shops, short courses, and profession societies. Practicing Arborists perform actual tree care practices, while Consulting Arborists give recommendations but don’t actually carry out the tree care procedures. Your particular situation will determine which type of arborist you will need.

Professional arborists can provide a wide variety of technical services. These services include:

  • Pruning- The purpose of pruning is to promote tree health, proper tree form, and to create a safe environment in the area surrounding the tree. This is accomplished by removing branches with weak V-shaped crotches, branches that rub together, dead branches, damaged or diseased branches, branches that rub against some part of the house or other structures, and branches that compete for light. Pruning may also be used to repair damage caused by a wind or ice storm, and to remove branches that are a potential hazard to objects below them. An arborist is trained to work safely with all sizes of trees. One pruning practice a trained arborist will not promote is Topping.
  • General Care- The best way to avoid tree health problems is to use proper care procedures. An arborist can deter-mine a tree’s fertility needs, and apply the right fertilizer, if necessary. An arborist also can monitor the tree for insect and disease problems, and take appropriate action to manage a prob-lem when necessary. An arborist may use soil aeration equipment to improve air movement in the root zone, when compaction is a problem. An arborist will use mulch around a tree to reduce competing vegetation, re-tain moisture, reduce soil temperature, improve soil structure (by increasing organic matter), and prevent mechanical damage from lawn mowers and weed wips. When trees have not been pruned, weak branches and double leaders can develop. An arborist can recommend cabling and bracing techniques to improve the strength of these weak points. Since trees often rise above many of the objects in the land-scape, they can be targets for lightning; an arborist is aware of the best methods available to protect high value trees from lightning strikes.
  • Removal- Occasionally, a tree must be removed because it is creating a potential hazard, is severely damaged or dead, is too close to a building, or is interfering with new construction. Arborists are trained and equipped to safely remove trees without harming themselves or surrounding property.
  • Consulting- Before building near established trees, changing the grade (soil level) around trees, or when attempting to determine the value of a damaged tree, homeowners may wish to enlist the help of a trained arborist. Many arborists give recommendations on preventing construction damage to trees; they may also appraise the dollar value of trees for tax, insurance and casualty loss purposes. Some arborists also will develop a tree planting plan which may include information on species selection, type of planting stock, planting lo-cation, and required post-planting care. Planting of trees and post-planting care is sometimes carried out by arborists.

Be aware that owning a truck and chainsaw does not automatically qualify someone as an arborist. Check out our Choosing an Arborist publication for more information on how to find a qualified professional. We also have a list of consulting arborists that provide service in Iowa


This artile is a web-based modification of the original publication "F-366 How to Hire an Arborist" prepared by Tivon E. Feeley for ISU Forestry Extension