The Urban Arborist is a professional tree service that is fully licensed, insured and bonded. We provide tree care to the San Francisco Bay area. All work is performed or directed by a second-generation arborist certified by the ISA (International Society of Arboriculture) Proper climbing and pruning techniques are used and we are adequately equipped to perform any job.
Our services include structural pruning, reduction pruning, vista pruning, removals, emergencies, and diagnosis. Click any service below for more info.
Most trees benefit from regular structural pruning: the reduction of the density of a tree's canopy to prevent wind damage and increase light levels. In this practice, the focus is on cutting unwanted branches back to their origin, leaving a strong and simplified network of branches that will have a chance to grow in a way most beneficial to the tree as a whole.
Generally, structural pruning is preferable to crown reduction (see below) for the overall health and safety of a tree, though sometimes a fusion of these methods is utilized. Upon doing a risk assessment of a tree we can determine the best course.
Crown reduction or "drop crotching" is sometimes required on a tree which is growing too large for its surroundings. This is a common occurrence in urban settings. A tree may be growing into power lines or a neighbor's building, or may pose a threat to an area frequented by pedestrians.
Although crown reduction is not always recommendable it may at times be a plausible option, providing it is done by an arborist skilled in the technique. The use of this form of pruning requires cuts to be made that do not go back to the tree's natural boundary, which can leave a tree more susceptible to decay. Similar to topping it can stimulate rapid epicormic growth in certain species, a setup for the development of poorly attached branches requiring frequent maintenance.
If not ideal, crown reduction is often preferable to the all-out removal of a tree (and the prospect of having to wait years for a new tree to replace a privacy screen of foliage). Some species, such as ficus microcarpa, are more tolerant than others to this practice. Some trees, such as birch, respond very badly indeed to reduction cuts. Given the circumstances we will advise accordingly.
Although pollarding is a legitimate technique it is one we rarely use. It is frowned upon generally as it is often confused with topping. In pollarding, a young tree is trained and maintained to an established size by cutting all but the central leader and a few structural branches. Smaller branches are cut back to the trunk and eventually a knuckle forms. All subsequent sprouts are pruned to within an inch or so of this knuckle on a regular basis (e.g. every 2 years). Although the result of this leaves a tree looking remarkably bare for a time, it is not a bad way of maintaining a tree at a specific size. Pollarding is only appropriate with some species (e.g., London Plane, Sycamore, Linden).
This type of pruning involves tailoring a tree's foliage such that a view is restored while the tree's health is kept in tact. Usually a tree that is pruned properly will enhance a view.
At times removing a tree is necessary. There is an art to removing a tree safely and efficiently. If this is determined to be the best course of action we are set up with the necessary gear and have years of experience doing large and precarious removals.
Josef Sikelianos, Owner
ISA Certified Arborist #WE-9111A
Ca. Lic. #994610