An arborist is a certified professional focused on arboriculture, the science involving the cultivation, management, and study of trees and other woody plants. They are often called tree surgeons or tree doctors because their primary goal is to maintain tree health and longevity in urban and suburban settings. Arborists do cut down trees, but removal is typically a last resort or a necessary safety measure, not the main function of the profession. They use extensive knowledge of tree biology to assess a tree’s condition and determine the most appropriate course of action, ranging from preventative care to complete removal.
Defining the Arborist’s Core Mission
The primary role of a certified arborist is the preservation and health management of individual trees. This focus distinguishes them from general landscapers or loggers, as arborists apply a scientific approach to tree care. They perform detailed diagnostic work, often looking for subtle signs of stress, disease, or pest infestation that may not be obvious to an untrained eye.
Preventative care is a large part of this mission, including techniques such as air spading to alleviate soil compaction around roots. Arborists also use specialized pruning techniques, such as structural pruning, to guide a young tree’s growth and ensure long-term stability. For mature trees with structural weaknesses, they may implement cabling and bracing systems to mechanically support compromised limbs and reduce the risk of failure. Professionals with International Society of Arboriculture (ISA) certification have demonstrated the technical competence and experience required to manage tree health effectively.
Tree Removal: When and Why Arborists Cut Down Trees
When tree preservation is no longer possible, an arborist will strategically recommend removal to protect people and property. One reason is the presence of irreversible disease or severe pest infestation, such as advanced decay or systemic problems like Emerald Ash Borer. Removal prevents the spread of the issue to nearby healthy trees, and the decision is made only after confirming that treatment options are exhausted or ineffective.
Another justification for removal is severe structural damage that makes the tree an imminent hazard. This damage includes extensive internal decay, large cracks in the trunk, or root system failure causing the tree to lean dangerously toward a structure or power line. Proactive removal is a necessary safety measure when the risk of the tree failing during a storm is too high. Removal may also be required for site planning, such as new construction projects or when invasive roots threaten to damage foundations, sidewalks, or utilities.
The Technical Expertise Required for Safe Removal
The physical process of tree removal, especially in confined residential spaces, demands a high degree of technical expertise from the arborist. Unlike simply felling a tree in an open forest, urban removal often requires sectional felling, where the tree is dismantled piece by piece from the top down. This process relies on complex rigging systems, utilizing ropes, blocks, and friction devices, to control the descent of heavy limbs and trunk sections.
Arborists are trained in mechanical advantage systems to safely manage large loads and direct debris away from homes, landscaping, and property lines. Specialized equipment, including cranes, bucket trucks, and advanced climbing gear, is employed to access and remove trees in high-risk locations, such as those near power lines. The arborist’s training ensures strict adherence to industry safety protocols, minimizing the risk of accidents and property damage during the inherently hazardous operation.