SINCE THE MOUNTAIN PINE BEETLE EPIDEMIC took root in British Columbia in 1993, its devastating effects have largely slipped under the American building industry's radar. But not for much longer. The endemic is fixing to throw a dangerous kink in builders' supply chains.

Economist Henry Spelter, with the USDA Forest Service's Forest Products Lab, estimates that roughly 80 percent of the lodgepole pine in British Columbia is affected by the epidemic. And with approximately 65 to 70 percent of the lumber from the area—about a third of Canada's total production—ending up in the U.S., this is a foreboding sign for U.S. builders.

A series of relatively mild winters sparked the beetle population explosion. Further adding to the beetles' unfettered proliferation is that the outbreak occurred in a protected provincial park. Forest officials were mired in red tape before getting permission to cut down parts of the forest to contain the beetles. The efforts have been largely unsuccessful at curbing the infestation.

Although salvage harvests turn the destroyed trees into lumber, area sawmills struggle to keep up with the volume. Spelter says, “The bottom line: [The beetles] are killing far more trees than we're able to process.

British Columbia's sawmill production has jumped 29 percent—compared to 16 percent for U.S. mills—in an attempt to process the felled trees before the wood deteriorates. Although builders can look forward to an extra three to four million board feet in the lumber market in the next year, “after five to eight years, this present glut will turn into a slowdown and then into shortage,” Spelter predicts.