Logging is the process of cutting down trees, an element of the task that requires a skilled professional. A tree feller is the person who cuts down the trees, while a feller buncher is a machine capable of cutting down a single large tree or grouping and felling several small ones simultaneously. An arborist, also known as a tree surgeon, is a professional in the practice of arboriculture, which is the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants in dendrology and horticulture. Arborists are trained to understand the needs of trees and provide services such as pruning, fertilizing, pest control, and removal. They can also be hired to inspect trees for wildlife or to provide expert witness testimony in legal cases.
Before undertaking works in the UK, arborists have a legal responsibility to inspect trees for wildlife, especially bats, which are granted special legal protection. When personal safety is an issue or when the tree is being removed, arborists can use “spikes” (also known as “gaffs” or “spurs”) tied to their chainsaw boots with straps to ascend and work. A feller-stacker is a motorized vehicle with an attachment that quickly cuts and collects several trees in the process of felling them. The undercut or notch is the guide or aiming groove of the tree and is a V-shaped notch placed on the side of the shaft in the direction of the intended fall. Chemicals can be applied to trees for insect or disease control by application to soil, stem injections, or spraying. Performing work on protected trees and hedges is illegal without express permission from local authorities and may result in legal action, including fines. In France, a qualified arborist must have an Ornamental Tree Management certificate, and a qualified arborist must have a Tree Pruning and Care certificate; both delivered by the French Ministry of Agriculture.
Trees in urban landscape environments are often subject to disturbances, whether human or natural, both above and below ground. Some commonly offered services are considered unacceptable under modern tree standards and can severely damage, deface, weaken or even kill trees.