Forestry companies that have suspended production include West Fraser Timber Co and privately held Tolko, among the largest Canadian producers, and Norbord Inc, the world's largest maker of oriented strand board, a plywood-like material used in house building. Mamtora said West Fraser's shutdown represents a loss of about 6.7 percent of interior British Columbia's lumber production and 13.8 percent of Canada's plywood production, while Norbord's shut mill represents 5.6 percent of Canadian production of oriental strand board. The companies said the facilities were shut due to evacuation orders and nearby fires, although the sites themselves were not burned. James Armstrong of Armstrong Investment Research said the shutdowns will exacerbate the low supply for an already tight market. "The question is what happens longer term," he said. "We don't know what happens with the fire yet. Longer term, if it misses the mill and doesn't do much, it probably won't have a huge impact."