An earth auger has a center shaft and a helical flighting extending along the axis of the shaft. The flighting and the center shaft have opposite ends that are identical in construction, so that the auger can be driven from either end by a power unit.

A portable hydraulically driven posthole digger is provided. The present invention is mounted to an existing loader-type tractor or skid steer loader by the use of a ball and socket type attachment such as a trailer ball and trailer tongue apparatus. The tongue is mounted vertically above the post hole digger and the trailer ball is mounted on the loader such as the bucket on a front end loader. The posthole digger's hydraulic motor is powered off of the existing hydraulic system of the equipment being used. This configuration not only provides an inexpensive method of digging post holes, but further requires a minimal amount of mounting hardware and can be easily removed and stored when not in use.

A directional boring device is provided for attachment to a carrier having a power source for providing a first power supply to the boring device for moving the device and a second power supply for operating the device. The boring device includes an attachment frame, and a selectively attachable first coupler for coupling the attachment frame to the first power supply to permit movement of the device. A drill tool assembly is provided that includes a drill head, a drill stem attachable to the drill head, a drill bit attachable to the drill stem and a drill assembly power transmission. The drill assembly power transmission imparts rotational and axial movement to the drill tool assembly whereby the drill assembly transmission is capable of moving the drill head and drill stem in a path generally parallel to the plane on which the carrier rests. A selectively attachable second coupler is provided for coupling the second power supply to the drill assembly power transmission for permitting the carrier power source to supply power to the drill assembly power transmission to operate the drill tool assembly.

A drive shaft permits driving two different driven shafts, such as those used on powered earth augers, from a single power source, whether the driven shaft has a circular cross section drive coupling, or a hexagonal cross section drive coupling. In one form an adapter can be slipped over a hexagonal shaft to receive a circular cross section drive coupling, and in another form, a shaft is provided with two axially displaced portions. An outer end portion has a hexagonal cross section, and a slightly larger circular cross section shaft portion is positioned adjacent the power unit.

A truck mounted crane is equipped with an earth boring bit apparatus which can be attached to the end of a crane boom to excavate holes prior to the erection of signs or other elevated pole mounted structures. The earth boring bit apparatus includes a earth boring bit attachable to a gearbox which may include an extension shaft to permit its use on the crane. The crane also includes high capacity hydraulic lines suitable for actuating the earth boring bit, which also includes a drum for collecting earth as the hole is bored so that the crane can be used to remove the debris as part of the same operation in which the hole is bored.