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Salvage logging science offers pros, cons in fire's wake By Vickie Aldous Ashland Daily Tidings The debate over salvage logging can be dizzying. Logging proponents say the practice helps recover economic value from burned trees, provides jobs, raises revenue for restoration activities and reduces the risk of subsequent wildfires and insect infestation of decaying wood. Salvage logging also leaves behind scattered debris that can slow erosion and removes dead trees to allow newly planted seedlings to thrive, they argue. But those against salvage logging say it increases soil erosion, compacts soil and encourages the spread of invasive weeds. Left in the forest, burned trees fall in streams and form pools needed by fish, replenish soil and serve as habitat for animals, salvage logging opponents say. The debate is heating up as U.S. Forest Service officials mull salvage logging areas of the Biscuit Fire that burned 460,000 acres of the Siskiyou National Forest and only died out earlier this winter. "Severely burned landscapes are more sensitive than green landscapes," said James McIver, ecologist and research coordinator for the Blue Mountains Natural Resources Institute Forestry and Range Sciences Laboratory in La Grande. "We should be more careful on burned landscapes if we're worried about things like sediment transfer and reduced soil productivity." McIver gathered 21 studies from around the world that dealt with the environmental effects of logging after wildfires, with the results published in 2000 by the U.S. Forest Service's Pacific Northwest Research Station. McIver said understanding the effects of post-fire logging is important given the fragile nature of wildfire sites. Soil disturbance and erosion vary based on the type of logging activity and whether roads were built, the studies compiled by McIver found. "It's the road building that causes the most impact," he said. Along with the Biscuit Fire salvage proposal, Medford District Bureau of Land Management officials also are considering salvage logging a portion of the 11,700 BLM acres burned by the Timbered Rock fire near Shady Cove last summer. McIver said science can shed some light on the arguments for and against salvage logging. One study estimated 90 percent of sedimentation from logging activities came from road building. Another study found erosion from logging was seven times that of undisturbed areas, but erosion from roads and landings was 100 times higher. A study on various types of logging found that tractor skidding caused the most soil disturbance, followed by cable skidding, tractor skidding over snow, skyline systems - in which trees are carried by a ski chairlift type retrieval system - and helicopter logging. Tractor skidding disturbed 36 percent of the soil, while helicopter logging affected just 0.7 percent of the soil, the study found. "With helicopter logging, it's as if God came into a stand and lifted the trees out," McIver said. "There can be some disturbance from felling. Helicopters are the least disruptive but the most expensive." Despite research showing soil disturbance from logging, especially for ground-based logging systems, results of studies on the related areas of sedimentation, erosion and water run-off were mixed. Several studies found increased sedimentation, erosion and run-off after logging compared to unlogged areas, especially on steep slopes. But a few studies reported no increased erosion and sediment, and some of the studies which found increased sedimentation also observed it was short-term, with watershed recovery taking place in three or four years. Sedimentation from post-fire logging can be difficult to measure because of the overwhelmingly larger amount of sedimentation caused by wildfire itself, some researchers said. Logging can actually reduce soil loss by 95 percent because of debris left scattered on the ground, one study reported. However, ground-based logging can compact soil and lead to more run-off, another study found. For land managers interested in jump starting the growth of a new forest, one study observed that logging sites prior to planting trees can cause seedlings to grow 17 percent taller. But logging also carries the danger of encouraging invasive weeds, researchers found. The probability that insect pests will infest burned trees and spread to green stands can be reduced by logging, several studies found. By the same token, removal of the trees decreases habitat for some animals, especially cavity-nesting birds, and lowers the numbers of insects used as food by various animals, numerous studies reported. "Removal of large dead trees can decrease the attractiveness of the site to fire-adapted birds," McIver said. "There are consequences even if you remove trees as gently as possible." Post-fire logging can increase habitat for species that prefer more open conditions, researchers observed. As for whether logging can reduce the risk that burned sites will be swept again by wildfire, McIver said no research has been conducted to prove or disprove the "reburn hypothesis." "That is a wide open area. It seems like a no-brainer, but there has been no research," he said. While many of the studies on post-fire logging show clear results, further research is needed to more completely understand the effects of the practice, according to McIver. However land managers choose to treat burned forests, they should carefully monitor the results, he said. LINKS: DAILY TIDINGS: Main | News | Sports | Business | Obituaries | Opinion | Columnists | AP News | Subscribe | Archives | Weather | Classifieds | Contact Us | Privacy REVELS: Main | Calendar | Dining | Movies | T.V. OTHER: Road Cams Copyright 2003 Ashland Daily Tidings 541.482.3456. 1661 Siskiyou Blvd., Ashland, OR 97520. Ottaway Newspapers, Inc. - Advertisers -