The roots do not stop at the line where one property becomes another.

Roots ignore property lines completely. The tree draws from soil that is legally divided, and what falls, spreads, and takes hold pays no attention to where one holding ends and another begins. Ownership is a human overlay on a system that is continuous underneath.

A good deal of neighbourly conflict comes from expecting living things to respect paperwork. More usefully, so does a good deal of family and workplace conflict, where influence spreads well past the boundaries of roles. Rather than insisting on the lines, it is often more productive to accept the spread and negotiate it. What is shared underground usually matters more than what is divided on the surface.