Dry kilns transformed lumber from its green, or wet, condition into a low-moisture product suitable for sale and economical transport by using controlled heat and steam to remove excess moisture and produce quality, straight lumber. The old kiln along the sawmill side of the trail system is one of the few structures remaining from the 20's and serves as a very old reference point in the immediate area against which other changes can be compared and documented. In the old kiln, pine lumber was dried to the desired moisture content in less than 72 hours, and its capacity was 300,000 board feet, or about 35 truckloads of finished lumber every 72 hours. Lumber was conditioned on the upper level by an updraft of steam from below. The new kiln along the kiln loop had about the same capacity, but its steaming process was the opposite, with flow from above to the lumber below, and it was not quite as efficient as the older unit, requiring a longer drying period.