There is a ribbon tied in a tree, that’s my corner, isn’t it?

Not necessarily. Ribbons can be tied to trees and even wooden stakes for many reasons, such as to mark reference points, buried utilities, well and springs, proposed power lines, soil borings, clearing limits for construction, hunting spots, bee nests, and even flowers. Many driveways have been built on the assumption that the flagging or ribbon tied in a tree was the property line, only to have to move the driveway later.