Approved Plans and Documents - OPW22/0303

                                                                                     Consult Arborist

7.3 ESTABLISHING TREE PROTECTION
Figure 9 shows a typical representation of a tree protection system. Tree root systems are
generally shallow in nature with most of the roots found within the top 1m of soil and a higher
density of roots found closest to the surface where moisture and nutrients are more readily
available. The function of the TPZ is to ensure that the tree has a viable root system, so the
tree has a functional future as an amenity asset within the development.

The structural standing of a tree is linked to critical aspects of roots (found in the TPZ) to bind
the soil and create a mass that the tree can anchor to. These roots consist of ‘Secondary roots’
(medium size) and ‘Tertiary roots’ (small size).

Primary roots (large size) found in the SRZ connect the tree to the anchor system. Primary
roots by themselves do not bind enough soil to create a stable anchor system.

The shallow nature of tree roots should be taken into consideration when working close to
trees and when installing the tree protection fencing for the Tree Protection Zone.




                      Figure 9: Example of an ideal generic Tree Protection System




7.4 TPZ SIGNS
The signs identifying the TPZ / ‘No-Go Zone’ are to be placed around the edge of the TPZ in
locations visible to the site as per Tree Protection Fencing Standards Australia marketing
media AS4970 – 2009.

7.5 TRUNK PROTECTION
Trunk protection, to prevent direct contact with the tree’s trunk and buttress roots can be
installed. This can comprise Geo fab/20mm thick hessian and wooden battens strapped/taped
to the tree’s trunk with a skirt over the buttress roots.




22_11_21_TMP_Stockwell_Medihub                                                         Page 16 of 22