@kiwipaul said:
Jacaranda is not a native tree so unless it has some special historical significence Tree Preseveration Order would not be applicable.Owners can cut down branches of tree overhanging their property but cannot make neighbours cut down branches of tree that are exclusively on the their property.
If the tree has been their for 100+ years it obviously was their when current parties moved in and so they have no complaint as they new the situation when they bought their nice new property.
I suspect also a special resoloution is required for a strata to pursue legal action and this requires a motion passed by 75% of the owners. As their are only 3 all need to agree to this action.
Hi
The tree preservation part is not quite true. Tree preservation orders can apply to any significant tree and it is usually the height and girth of the trunk, not whether it is native, that applies.
Three 100+ year old jacarandas would likely fall into the category (particularly if you are talking about a dispute over views these trees are obviously somewhere in Sydney harbour 
). There is a dubious new category that the land and environment court can determine as a ‘spite hedge’. Hopefully that would not apply.
However, the rest should apply given that the complaining apartments are only 7 years old and 75% resolution is required to pursue action. As the OC of the block containing the jacaranda trees, I would politely decline any further correspondence on the matter….