The corners of the lip of a power shovel adjacent the digging edge of the lip are protected by removable guards, more specifically in the form of teeth, and projecting forwardly at each corner; each corner guard preferably includes an integral shroud embracing the portion of the digging edge of the lip which intervenes between the corner and the next adjacent dipper tooth, the latter being of any preferred form. Additionally the guard is so constructed as to present an extension at the rear thereof constituting a portion of the side wall of the dipper.