How Arborists Work

Arborist Services

Arborist John Massing sprays pesticide at the base of a horse chestnut tree in Central Park in New York City.
Arborist John Massing sprays pesticide at the base of a horse chestnut tree in Central Park in New York City.
Melanie Stetson Freeman/The Christian Science Monitor/Getty Images

­Arborists are well-versed in arboriculture, the study of trees and how they grow, and they spend years receiving specialized training to secure their positions as proper custodians of trees.

Because the health of the trees around us is important to the entire environment, and not just humankind, arborists must know every angle there is to tree care. Taking care of trees is a very specialized practice, and it not only requires a great deal of knowledge but a lot of skill and experience. Much of tree care involves climbing high into the branches, which can be very dangerous and requires serious training.

One of the main services an arborist provides for cities, states and other organizations is pruning. Although branches are­ certainly important to a tree, there are times when it's necessary to remove branches to promote proper health and growth. Branches that rub against each other, for instance, damage a tree's bark, so arborists can and will remove them if they grow too close together. An arborist can also remove branches that are weak, diseased, insect-infested or in the process of dying, since one dead branch can cause the entire tree to decay. Any limbs that create a hazard or obstruction for people, including drivers, should also be cut for safety's sake.

Entire trees sometimes have to be removed by arborists, too, although it's a last resort. An arborist will only remove a tree if it's dying or dead, if it causes an obstruction or hazard that can't be fixed by pruning or if it rests in a spot that will undergo construction. If a business wants to remove a certain number of trees to develop buildings and other infrastructure, an arborist can approve or deny any plans and provide consulting on future plans for tree planting around the development. If businesses illegally remove trees without permission, arborists have the ability to issue citations with big fines -- movie director and actor Tyler Perry, for instance, was fined $177,000 for illegal deforestation around his Atlanta home in 2008 [source: Brown].

Storms can cause lots of damage to trees, and after a storm it's an arborist's job to safely clean up the mess. They clear away any branches or limbs that fall onto the road or on top of houses, cars and power lines. They also remove any trees irreversibly damaged by the storm.

Finally, many arborists are typically eager to promote tree planting and tree growth, and have extensive knowledge about how and where to plant trees. Location is especially important in tree planting. Knowing the specific climates and regions in which a tree can thrive and being aware of the various diseases and insects a tree can fall prey to will ultimately affect the success of that tree.

How does an arborist actually become an arborist? Find out on the next page.