A swing yarder is a mobile piece of heavy duty forestry equipment used for pulling logs from the woods to a logging road with cables. The swing yarder is also known as a grapple yarder. In any logging operation, it is necessary to transport the harvested tree from the stump to a landing for transport to market (usually on a truck). If the ground is relatively flat it may be possible to transport the tree or logs cut from the tree on a wheeled or tracked machine. However if the ground is too steep for the operation of such machinery, it is common practice to rig some sort of a cable system for moving the wood. The swing yarder is one of several varieties of machines that have been used for this purpose.