The City prunes trees in order to maintain them to the highest possible standard and minimise any potential risk that may be posed to the public.
Pruning is only carried out by qualified Arborists, with a minimum AQF Certificate 3 in Arboriculture.
All pruning is in line with the Australian Standard for Amenity Pruning, AS 4373 - 2007 and is only carried out to remedy poor structural conditions, remove deadwood or parts of a tree affected by a pathogen, provide clear sightlines for vehicles and pedestrians, or to maintain the legislated requirements for clearance from powerlines.
Lopping, topping and flush cuts are not acceptable pruning practices and will not be used on any tree on a verge or in a park.
The City aims to provide the following clearances:
- 2.5 metres over a path or verge
- 4.6 metres over a road.
Pruning is valid for the following reasons:
- To ensure clearance from powerlines and street lighting as per the Code of Practice for 'Personnel Electrical Safety for Vegetation Control Work Near Live Power Lines'
- To ensure visibility of street signage
- To allow appropriate sightlines for vehicles and pedestrians
- To provide 4.5 metre minimum vehicular clearance along roads
- Where an unacceptable level of risk exists within the tree and pruning will enable its longevity
- To define the form of a tree
- To remove significant deadwood
- Solar Panels as determined by the City's Consulting Arborist.
The City will not prune a tree to its detriment and as such pruning is not undertaken for the following reasons:
- Leaf, fruit, flower or bark drop
- Appearance (for shaping or because the tree is "ugly")
- Minor overhanging of fence lines
- To reduce its size
- To discourage the presence of fauna
- For advertising signage.
If trees overhang a property, pruning is only carried out if there is significant influence over a dwelling or where an adverse structural condition exists.
Sometimes the pruning of roots may be necessary to stop damage or disruption to infrastructure at or below ground level. Root pruning is a very effective way to prevent damage to infrastructure and is used instead of removing a healthy tree.
Root pruning will be used on trees when:
- There is disruption occurring to infrastructure that can be seen
- There is a significant trip hazard present.
Root pruning is not undertaken when:
- There are small surface roots that can be covered by top dressing mix or mulch
- To make lawn mowing easier.
Root barriers are a highly effective tool in controlling the growth of roots around infrastructure and are used around species of trees that have a vigorous root system.
Root barriers are typically a plastic membrane that is put into a trench once the trees roots have been identified and cut by hand to ensure unnecessary damage does not occur to the tree.
As a minimum, the City will install root barriers to a depth of 600mm and their use will be determined following an inspection by the City's Consulting Arborist.
Where there are claims of damage to structures or below ground infrastructure, the owner of the property is required to present a technical report from the relevant profession, including:
- Structural engineer
- Licensed builder
- Licensed plumber.
The City is committed to maintaining and increasing a healthy tree canopy. The removal of trees on public and private property is carefully considered before proceeding.
Removal of trees on City land will only occur when all options for keeping the tree have been exhausted and where the following circumstances exist:
- The tree is dead
- Where an unacceptable level of risk exists within the trees structure and remedial techniques cannot rectify the issue
- The tree is suffering from a disease where remedial techniques will not prevent further spread of the disease, and the removal will be of benefit to other trees around it
- The tree is causing significant damage to infrastructure and suitable documented evidence is provided by a qualified professional
- To facilitate the placement of a permanent vehicle access crossing where there is no other viable option (subject to the Amenity Valuation process).
If a tree is to be removed, the City's Consulting Arborist will document basic details, along with the reasons for removal and a photograph of the tree prior to removal taking place (except in emergency situations that may not allow for this and public safety is the first priority).
Tree removal is not undertaken for the following reasons:
- Leaf, fruit or bark drop
- Tree size
- Dislike of the species
- The presence of fauna or insects (insect pests are treated through various techniques)
- If the tree is an inconvenience during construction projects
- Solar panels, television and pay-tv reception etc.
Request for the removal of a tree needs to be made in writing to the City.
The need for pruning, root pruning, root barriers and removal are assessed by the City's Arborists, with consideration for the species of tree, environmental conditions and impacts, along with constraints of the location.
The City's Consulting Arborist can approve the removal of trees that comply with the above criteria. If an application for removal is made to the City that is contrary to this, the matter may be referred to Council.