Abstract: An elongated upstanding shank is provided including structure for manually applying rotary torque to the upper end of the shank. The lower end of the shank supports an elongated blade therefrom including a first horizontal upper end mounted at one end of the shank above the lower terminal end thereof for rotation with the shank. The first horizontal upper end of the blade extends outwardly from one side of the shank and terminates in a downwardly and inwardly curving portion which in turn terminates in a downwardly and inwardly inclined lower end portion of the blade. The downwardly and inwardly curving blade portion is slightly twisted about its longitudinal axis to position the lower terminal end of the blade lower end portion slightly outwardly of a second side of the shank facing outwardly in a direction disposed substantially 90.degree. from the direction in which the first side of the shank faces outwardly.

Abstract: An elongated upstanding shank is provided including a ground piercing lower end and an upper end including structure for applying rotary torque to the shank. The lower end portion of the shank supports a generally horizontally disposed U-shaped blade therefrom including a pair of generally parallel upper and lower arms joined at one pair of corresponding ends by an integral curved bight portion. The other pair of corresponding ends of the arms are supported from the shank at points spaced therealong. At least the lower arm and the adjacent portion of the bight portion include a sharpened edge facing outwardly of one side of an upstanding plane containing the U-shaped blade and the shank. The blade comprises a thick elongated strap metal member bent into U-shaped configuration and the portions of the blade defining the lower arm and the adjacent portion of the bight portion are disposed with their width extents disposed generally normal to the aforementioned plane.