This is most likely a case of a ghost that won't move on from their death. This woman might know she's dead, or she might not. Either way, someone will need to convince her that she doesn't belong here anymore. If you are not up to the task, and there is no shame in admitting such, then you should find someone who has experience with these situations. You have nothing to fear from this woman, she has no power over you or the physical world. As long as you are no afraid and believe in yourself, you will be safe.
A residual haunting is the result of a strong emotional state that imprints itself on an area. This type of haunting is almost like a recording, playing itself out over and over again; similar to an echo as you mentioned.
If she is actually interacting with you, I think it's safe to say that it is an intelligent form of a haunting. Intelligent hauntings are usually associated with human ghosts that can interact, communicate, etc with the living. They are aware of what is going on around them. That being said, it is possible that this woman just doesn't know that she has crossed over yet, so her spirit keeps coming back to a place (even if it is long gone) that once offered her comfort and peace in life.
I actually read a similar story to this one in one of my books. The book is called Phone Call from a Ghost , written by Daniel Cohen. There was a story in it called "A Hitch in Time." A woman walked into a class room and the sounds and season outside of the window, as well as the room itself, changed. Then, the woman saw a lady standing in front of an old fashioned bookcase, searching for something on the shelves. The woman did some research and found came to find out that the woman was a piano teacher that had died some years before.
Anyway, if she isn't posing a threat to you or your mother, I would just leave her be.
Thanx to all for the input. Yes I wanted a friend who is capable of helping ghost, something I can not do, but again its not my land and Mom believes I should drop the matter. I wont be able to do anything either way. Mom told me she believes I may have seen the lady on her land as there was once a garden there and the ladies house next to that. Being a devout Christian, however Mom has forbidden any further attempts by me to interact with, help out or even discuss the matter of a trapped spirit. She feels if it is a spirit it is there for a reason and it is best to ignore it. I disagree but I will respect her wishes. Thanx again to all. Peace, David
