There could be different regulations depending on where you live. In my area, shrubs can be planted anywhere as long as they don't grow over onto the neighbors lot. I'm not sure about trees. All of our neighbors trees seem to have branched over other neighbors land, but no one ever complains.
I think I have my own property at bangkok and well in my area or you can say in any bangkok property there is different regulations of certain range.so in your property there should be some range so just take a information about it.
More to the point....when you can begin to cut them when they cross your property line lol..What is annoying is if they fall and land on your property do you have to clear them away? I Do. There is a law about the air space and who owns what aswell..so not sure about encoachment from above even if the roots are on their side! Call your Town Zonning Dept.
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