Arborists look after trees.
They encompass Tree Surgeons, Tree Loppers, Consultants, Tree Planting Contractors, Foresters and other professions.

This work can involve removing sick or damaged trees (or parts),  removing or chipping prunings, controlling the size and shape of trees, repair of trees (e.g. bracing, propping, cabling branches to prevent them breaking), accessing trees by climbing or with a travel tower, planting new trees, transplanting large trees, controlling and removing unwanted root, controlling tree pests or diseases, or developing  tree management plans.
Trees in urban areas can often become a problem. Branches can fall onto power lines, buildings or other structures. Roots can damage pavement, fences and building foundations or block drains.

• A tree lopper is someone who removes trees, but might not understand so much about how to grow or repair them.
• A tree surgeon will understand more about how to grow and care for the health of trees, but in addition, still have all the same skills of a tree lopper.
• Some people in this field may specialize, for example: stump removalists may provide a service to dispose of large stumps after the tree is removed. Stump grinding machines may be used for this. In some instances a stump may need to be dug out or burned. Removing a stump can result in soil subsidence, so understanding all of the implications of dealing with “left over” roots can be a significant area of study.

Where Do They Work?
Arborists often work for an arboriculture business, tree removalist or tree surgeon. Some are employed by municipal government or other public authorities. Some work in forestry and others in private enterprise. Many will start their careers climbing trees, but often with age, this type of work can become increasingly challenging. Later in their careers, some move on to being a consultant or manager or conduct tree inspections and write tree reports for councils. Others may leave arboriculture and find work in other areas of horticulture.

Non-climbing arboriculture assistants are employed to work ropes, lower branches to the ground and clear away branches. They may also operate a chipping machine. This type of work is less skilled than climbing, does not pay as much, and may be an easier job to get when starting out in this industry.
A skilled climber is always in demand, and can earn very good money however one should always consider whether this is a job you would plan to do for decades, or for a lesser period - as a stepping stone towards something else.

What is Needed?
Climbing is dangerous work if you don’t know how to do it properly (and use appropriate climbing gear).  Some arborists learn to climb on the job. Others learn by doing abseiling or rock climbing as a sport. Others may learn through a trade apprenticeship or specialised course.
Arborists also need to understand trees. Even a tree lopper, who is only removing trees, still needs to understand what woods are safe to climb on, and what should not be climbed. Different species of trees are stronger or weaker; some are prone to break, and others are not.
A good arborist needs to be able to identify plant pest and disease problems (particularly wood rotting diseases), and differentiate between perhaps 100 or more of the more commonly grown species of trees in their locality. They should also know enough about plant taxonomy to determine the plant family a tree belongs to - when they encounter a species they are unfamiliar with.
Courses in Arboriculture -Click for details 

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