Industrial burning of wood and vegetation can release a lot of smoke, which can cover a large area for extended periods of time. This kind of burning includes:
Prescribed (controlled) forest burning is not industrial burning. It is a forestry management tool used to reduce wildfire hazard and enhance wildlife habitat.
Open burning is used in agriculture to dispose of crop residue, clear areas for planting, and control pests and disease.
The forest industry is required to dispose of leftover slash and wood residue to reduce fire hazards. This can include burning materials following the Open Burning Smoke Control Regulation or using other disposal methods such as turning the material into wood products like mulch or wood pellets.
Slash is the leftover tree limbs, tops and other residue left by logging activities. There are two ways of burning slash, in piles or by broadcast burning.
Pile burning is when slash is piled together and burned during safe conditions, usually during the winter after it has been left to dry. The Open Burning Smoke Control Regulation establishes strict rules on what can be burned in land-clearing fires, where they can be located, the atmospheric venting conditions that must be present, and how long the burning can last.
Broadcast burning is where tree limbs, tops, and other residue are burned as they lie on the ground after cutting. The slash must be distributed continuously throughout the burn area to be burned effectively. This type of burning is usually done during very wet periods or with light snow cover in late fall or early spring. These fires are covered under the Wildfire Act and Wildfire Regulation and require a burn plan.
Wood debris from log sorts is disposed of through open burning. Stumps and roots encrusted with mud may be burned, resulting in dense smoke. This kind of burning is currently allowed through permitting, but may be subject to the Open Burning Smoke Control Regulation in the future.
Most sawmills burn the trim ends, slabs, bark, shavings and sawdust left after the logs have been cut. There are two problems with this practice:
Wood residue burning is controlled by the Wood Residue Burner and Incinerator Regulation