All of my brilliant friends who suggested that she is root stock coming from below the graft are, according to the University, absolutely correct. Rose growers in Colorado are advised to bury the graft one to two inches below ground to protect it from freeze. I have always done this; consequently, I wouldn't see her below the graft.
My grand friend, David, is also correct in his assertion that she is most likely "rosa gallica" some of the oldest rose stock known. As she was brought to England by my ancient ancestors - the Romans - I shall allow her to grow in honor of their gardening skill for this season at least. Thank you all.