North Platte - Pine Beetle_Water Project - Overview - Section 4

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Water From Colorado's Bark Beetle Forests -Project Overview Elder, Rhoades & Hubbard; USFS Rocky Mountain Research Station; 5/15/08 water and nutrient use in beetle-killed forests will vary based on site environmental conditions, overstory species composition and the density of the forest understory. Catastrophic pine mortality has created public anxiety and prompted a rapid management response to address concerns about elevated wildfire risk on state, private and federal forestland. The US Forest Service is currently using provisions of the Healthy Forest Restoration Act of 2003 (USDA/USDOI 2005) to expedite salvage of dead timber on National Forests across northern Colorado and southern Wyoming. Treated acres have expanded rapidly in recent years, but in spite of general public support for this work (Western Governors Assoc. 2006), active forest management remains highly controversial (Reeves et al. 2006; Rhodes 2007). Recent research on post-fire harvesting challenges the effectiveness of salvage logging for reducing wildfire risk and promoting forest regeneration (Donato et al. 2006). Similarly, environmental groups in Colorado and throughout the West have raised concerns that post-beetle outbreak salvage operations may impair water quality, site productivity, and watershed resources (Colorado Wild 2004). However, in the steep, rugged terrain of the headwater forests of the North Platte and Upper Colorado River basins the acreage accessible for salvage logging is limited and proper planning and timber sale administration can protect sensitive areas and watershed resources. Forest harvest will accelerate watershed change inbeetle-killed pine forests. Elimination of overstory interception by judicious clear cut harvesting has been shown to cause immediate and sustained increases in water yield and peak discharge from Colorado subalpine forest watersheds (Troendle and King 1985). The interception savings and increased snowpack accumulation in harvest openings yield measurable increases in streamflow as long as 20 - 30% of the forest cover is removed from a catchment (Troendle and Leaf 1980; Bosch and Hewlett 1982). However, snowpack gains may be offset by wind scour in large clearings (Troendle and Leaf 1980; Golding and Swanson 1986). Salvage operations typically create openings that surpass the size threshold (e.g. 5-7 tree heights / 100 - 200 m) beyond which snowpack losses become significant in lodgepole ecosystems (Troendle and Leaf 1980; Swanson 1988). In such areas, retention of logging slash generates a layer of surface roughness that conserves snowpack moisture accumulated in openings exposed to wind scour (Pomeroy et al. 2002). The effects of timber harvesting on water quality and site productivity increase with extent of physical soil disturbance (Feller et al. 2000; Briggs et al. 2000) and the amount of biomass and nutrient removal (Mann et al. 1988; Hornbeck et al. 1990), further justifying retention of logging slash. In spite of the urgency to respond to forest health threats, state and federal regulations require land management practices to sustain the delivery of clean water and protection soil quality and long term forest productivity. Current salvage logging in Colorado's beetle-killed forests is justified primarily by immediate Fuel Reduction objectives, though management priorities and specific practices that sustain Watershed Resources and promote Forest Regeneration may have greater long-term merit. The management response to this natural disturbance will set the trajectory of watershed and forest recovery for the coming century. Scientific and public skepticism regarding the