I think this song illustrates the grateful dead folk tale - the narrator gave Annie a proper burial and after ten years at sea is explaining why he did what he did. Presumably Annie, who is living on her own in a remote farmhouse, is shot tending her roses. Who would willingly put their head down in the roses? Thorns. He explains why he couldn't leave the body there. To me he finds the body relatively well preserved - is it winter and she was killed bringing in the last roses of the season. That would explain why the ribbons would be faded but Annie's beauty still intact. Her husband was away fighting - my guess on the opposite side of the narrator who would not need to explain why he buried a woman on the same - likely Confederate side. He might have known her name as relatives and friends fought on opposite sides or he may have learned the name after he came back from sea. The tender way Jerry sings it to me indicates that he is talking to Annie's loved one or ones. Perhaps the husband who has been looking for her for ten years. She probably was buried in the rosebush of the house which is now derelict.