Dear Abby: How do I handle a neighbor’s claim over my property?

Dear Abby: We just moved back to Southern California and into a gated community. My neighbor’s property is higher than mine, and she has a spiky, thorny hedge that’s growing over into my property and staining the side of my house. I went over and introduced myself, wanting to discuss the issue. My neighbor’s reply was, “That’s YOUR hedge!” The next thing I know, she has a person trim it and throw all of the clippings into my backyard for me to clean up. How do I deal with a neighbor like this?

— Thorny Relationship