“When lot was originally purchased the developer had originally staked out property line. At time of purchase buyer had landscaper install trees along designated property line. 6 years later, the adjoining lot has been sold and survey now indicates the property line is now different and trees are on neighbor’s property. Any options?”
You didn’t say options for what. If you want to enforce the incorrect property line as against the neighbor, you may be out of luck. You would need to check your local law (consult with a local attorney on this) regarding whether any innocent mistake regarding the location of a property line can mature into a property right. In many cases, the answer is no.
That does not mean that you are entirely without options. You may have a cause of action against the developer or surveyor for the financial losses you incurred due to their mistake. Or you may be able to get some compensatory right in the landscaping, even though it is on the neighbor’s property. Again, this is a farily complex area of the law, so a consultation with a local attorney would be advisable.