The U.S. Forest Service often lets logging companies buy trees felled by storms, a practice intended to generate revenue and eliminate wood that could spawn bug infestations and fuel wildfires. A recent study shows that salvage logging may do more harm than good, however. Cristina Rumbaitis-del Rio, a graduate student at the University of Colorado at Boulder, examined patches of spruce-fir forest in the Rockies where a 1997 windstorm blew down trees. She focused on areas that had been logged and on others that were untouched, and then compared both with parts of the forest that were unaffected by the wind. "Salvage logging was more of a disturbance to the ecosystem than the blowdown itself," Rumbaitis-del Rio says. Windblown areas had become lush, covered with wildflowers and berries, but logged areas remained largely barren, prone to soil erosion and nutrient loss. Because spruce trees grow only in shaded areas, salvaged land had 93 percent fewer spruce seedlings than land where downed trees were left in place.
Greg Aplet, a forest ecologist with the Wilderness Society, sees an important policy lesson in these findings. "Decisions to salvage logs are often couched in ecosystem rehabilitation and restoration terms," he says. "Cristina's results show that salvage logging has a measurable, dramatic, additive effect on the environment. In the spruce forests of Colorado, at least, the effects of salvage logging are no different than the effects of logging."