A wigwam burner is a waste disposal facility commonly used by sawmills in the Pacific Northwest during the first half of the 20th century. In the process of sawing lumber out of logs there is necessarily portions of the log that cannot be made into lumber. This includes the bark, sawdust, planer shavings as well as the 'slabs' or rounded portions of the log that are sliced off. By the second part of the 20th century markets for this 'waste' was often found, but before that it was the norm to burn it. The problem with burning it was that one needed to avoid burning the mill while disposing of the waste. The Wigwam burner (so called because of its shape) was essentially a large 'burn barrel'.
A conveyor usually fed the wood products in the top, and it was vented some around the base to control the fire. Screens at the top were designed to let the smoke out, but attempted to control the cinders and sparks which would threaten the area. In those days the pungent odor of wet wood burning was always associated with sawmills as the fires burned most of the time and smoked profusely. Environmental issues related to the smoke lead to them being banned in the 1960's, but by then their use was in decline. Mills and found a way to chip the slabs and larger pieces of wood and sell the chips for paper making. This left a much lower volume of waste, just the sawdust, planer shavings and bark. Today the bark is often ground and sold as 'bark dust' for gardening and the like, and the sawdust and planer shavings often find their way into wood pellets for pellet stoves, or sold for 'hog fuel' to burn under more controlled conditions to make steam for electric generation.
The Wigwam Burner shown here (near Mapleton, OR) has long been retired and has no conveyor to feed it as indeed even the mill that used to supply the material for it to burn is no longer operating.
The second photo was taken in 2010 in Sandy, Oregon. It depicts more traditional appearing Wigwam burner. Special thanks to Martha Havens for the Sandy Photo.