Y

	Yarding (yarding systems): in logging, the hauling of felled timber to the landing or temporary storage site from where trucks (usually) transport it to the mill site. Yarding methods include cable yarding, ground skidding, and aerial methods such as helicopter and balloon yarding.
	Yield Analysis: the study of forest yield over time using mathematical models and inventory data.
	Yield curve: a representation of stand volume, usually as a function of stand age, in graphical or tabular form.