Tree Management

PO Box 3453
Dural NSW 2158, Australia 
Mobile: +61 0407 103 895

ABN 71 324 020 793

Tree Protection


The Benefits of Trees

Trees on development sites that are proposed for retention must be adequately protected from damage during construction activities. The Australian Standard - Protection Trees on Development Sites (AS4970-2009) is used to apply these protection methods.

Trees reduce stress levels and excel patient recovery in hospitals as well as having aesthetic values.


* Providing wildlife habitat such as nesting sites, food sources and protection. 

* Trees with hollows are very important as nesting sites for some bird species.


* Trees provide shade and reduce temperatures within nearby buildings, which lowers cooling costs.

* Trees take up water which reduce storm water levels and prevent erosion.

* Trees aid in the reduction of winds and can alter wind direction.

Tree Protection Zones

Tree Protection Zone (TPZ)

The area that protects the above and equally important below ground parts of a tree. It is a formula (AS4970-2009) using the diameter of the trunk measured at 1.4m from the ground.

Structural Root Zone (SRZ)

The area around a trunk required for tree stability.

TPZ Encroachments

Tree Protection Zone Encroachments 

The area that the proposed development activities encroach into the applied tree protection zone. In accordance with AS4970-2009 less than 10% encroachment    is acceptable, over 10% is unacceptable and must be justified by the project arborist.

Protection Methods

Protection Methods 

These methods are applied to prevent damage to any part of the tree. May construction activities can be detrimental to long term tree health. These methods are also site and tree specific and assessed to meet individual requirements. 

Tree Care

During and post construction it is beneficial to ensure that each retained tree       has a favourable growing environment. The area should be weed free, mulched     and irrigation readily available of required. In some cases management plans     are required to monitor and manage the tree post construction.