Pruning and Maintenance
North Sydney Council maintains a huge network of public trees with over 17,000 street trees plus many more growing in Parks and Reserves. Council's in-house Tree maintenance Team strives to maximise the health and longevity of the Urban Forest to ensure ongoing amenity for the residents of North Sydney. The team inspects all street trees approximately every 18 months and carries out any necessary maintenance tasks as they are identified.
Council only prunes trees where the pruning is essential to maintain the health of the tree or to ensure safety of persons or protect property. Council prunes in accordance with the Australian Standard for Pruning of Amenity Trees (AS4373.2006) and will generally only prune for the following reasons:
- to provide clearance for traffic, and vision of essential traffic signage
- to allow pedestrian access
- to provide safety clearances around buildings and services
- to train young trees to an appropriate form
- to maintain a safe tree crown (ie remove dead or damaged branches).
Council does not prune privately owned trees however where private trees are encroaching into target clearance spaces, Council may issue a notice to the tree's legal owners requiring them to prune the tree.
Council prunes public trees in an effort to achieve the following target clearances.
- Over footpaths 2.4m
- on major arterial roads 4.5m over all lanes
- on local roads 2.4m over parking lanes and 4.5m traffic lanes
- around buildings and structures 1m or less if branches are thick and unlikely to move during wind.
Note: These clearances can only be achieved incrementally as the trees mature. Industry practice is to maintain branches on at least two thirds of the height of the tree and to not remove more than 25% of a tree's foliage in any one pruning event.
Cosmetic pruning encompasses pruning practices that are not essential to public safety or the health of the tree. Examples include:
- thinning for views or light penetration
- shaping for aesthetic reasons
- removal of overhanging branches beyond Council's target clearances
- shaping or selective pruning to improve visibility of advertising or other 'non-traffic' signage.
Council does not carry out cosmetic pruning but Council policy allows residents to make application to the Tree Preservation Officer to carry out cosmetic pruning at their own expense. Permission may be granted where such work will not compromise the health, safety or integrity of the tree or adversely affect public amenity.
Note: Council does not allow cosmetic pruning of any vegetation located on land zoned Bushland.
Powerline clearance is carried out by contractors working for Energy Australia. In general 1m clearance is required around service lines running from the street to private properties, and 1.5m clearance is required around the lines running along the street, plus allowance for one year's regrowth.
In the case of Aerial Bundled Cables, which is the single thick bundled wire used in some areas of North Sydney, the required clearance is reduced to 0.5m at pruning time with small twigs allowed to touch the wire between pruning events.
Planting on Public Land
North Sydney Council actively manages the "urban forest". All trees that have to be removed are replaced if the planting site is still capable of accommodating a tree. Council is also proactively identifying and planting in new locations in accordance with the Urban Forest Strategy. A proposed tree site must provide adequate space for the chosen tree to survive in the long term.
Council will endeavour to plant at least 400 street trees per annum and will follow the principles below when identifying locations, choosing species, installing trees and providing establishment care. Council will carefully evaluate the site to determine the constraints and the desired function of the tree. The species chosen will either reflect the character of the area where appropriate, or create a sense of identity, and should not pose any threat to the health or safety of the community or it's associated infrastructure.
New trees will be planted in locations where they will make positive contributions to the amenity of an area, and will not adversely affect adjacent properties, services or structures. For example, through effective tree spacing, solar access can be maintained to adjacent properties and where appropriate, scenic views maintained.
Horticultural characteristics that will be considered when selecting a street tree species include: fruit/flower/seed drop, suckering, root vigour, structural soundness, weed potential, poisonous or allergic qualities, foliage density, whether the tree is evergreen or deciduous, and appropriate habit and form.