Common use of Ground-Based Yarding Clause in Contracts

Ground-Based Yarding. Ground based logging usually involves the use of tractors, either tracked or rubber tired (rubber tired skidders) to skid logs to the landing. These machines use either powered grapple attachments or winch lines to grasp of the log, and require constructed "skid trails" for their operation on all but the mildest terrain. A related system used only with small logs and on the mildest terrain is forwarder logging, where a specialized tractor equipped with a small hydraulic boom loader travels into the logging unit and loads logs onto bunks that are mounted on a rearward extension of the tractor's frame - in essence a small self-loading truck designed with tires, gearing, and ground clearance that allow it to operate off-road. Another variant on ground skidding is shovel logging. A shovel, or hydraulic boom log loader, is an excavator that has been equipped with a log loading boom and grapple instead of an excavator boom and bucket. Most shovels are mounted on tracked undercarriages with generous ground clearance, providing some degree of off-road mobility. This capability is used in shovel logging, where a shovel walks off the truck road, picks up logs in a unit that has been felled, and passes them back towards the truck road using its upper structure rotation or "swing" function. This system is very efficient over short distances, since the same machine that does the yarding can load the logs on trucks. However, it is not used over long distances because of the amount of repeated log handling that becomes necessary as distance from the truck road increases. As with ▇▇▇▇▇▇-bunchers, shovels have no blade or other attachment capable of moving soil and do not require the construction of roads or trails to operate.