Black v Johnson (No 2)  NSWLEC 513
Tree Disputes Principle
The existence of a tree prior to the construction of a structure which has subsequently been damaged by the tree is not a matter likely to be taken into consideration on the question of whether or not some order should be made for interference with or removal of that tree or other remedial work. On that question, the seriousness of the damage and any attendant risks are the primary matters for consideration.
If interference with or removal of the tree or other work is warranted because of the extent of the damage the tree has caused or risks now posed by the damage, the fact that the tree was already growing in the vicinity at the time the structure was built is a matter which may be relevant and appropriate to take into account on the question of who should undertake any work and/or apportionment of the cost of such work.
However, it will also be relevant to consider whether or not the tree was self-sown or was planted. If it was planted, consideration will need to be given to the appropriateness or otherwise of:
i) the type of tree planted
ii) the suitability of the location in which it has been planted