The Role of Timber Salvage in Forest Restoration Why, Where, and When *

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1 The Role of Timber Salvage in Forest Restoration Why, Where, and When * John Sessions 1 and Stephen Fitzgerald 2 1 Professor, Department of Forest Engineering, Oregon State University, Corvallis, OR Professor, Extension Silviculture & Wildland Fire Specialist, Department of Forest Resources, Oregon State University, Corvallis, OR john.sessions@oregonstate.edu Abstract Timber salvage has long been recognized as an important tool for value recovery and as a silvicultural tool on lands managed for timber production. Timber salvage can also be an important tool for re-establishing complex forests by providing the financial means for accelerated forest restoration and stand maintenance, and to create a work-safe environment and sound snag retention strategy until the new conifer forest can again be producing large green trees and future snags. This paper outlines the contributions that active management can make in re-establishing conifer forest for lands managed for older forest wildlife habitat. 1. INTRODUCTION Salvage of timber following disturbance has been a standard operation on private and public forests for many decades to recover value, reduce future fuel loadings, and prevent insect buildup and spread. Two early salvage operations stand out. One is the Tillamook Fire Salvage in Oregon, estimated to have been about 8 billion board feet; the largest fire-killed timber salvage in United States history. Another is the New England Hurricane Salvage, a 425 million board foot salvage led by the Forest Service following the 1938 New England Hurricane which reportedly blew down 3 billion board feet in New England (Ober 1988). Recently Hurricanes Katrina and Rita reportedly damaged up to 20 billion board feet in the southeast USA. How much will be salvaged is unknown. Currently the largest insect salvage in North American history is ramping up in British Columbia where as much as one billion cubic meters of lodgepole pine (equal to 2 years of total US wood consumption) is estimated to have died or is at high risk from the mountain pine beetle over the next ten years. As brought out by Lyman (1945), the fuel hazard after wildfire reduces little for 20 years and may persist in substantial degree for 40 years or more (Brown and Davis 1973). Although recent salvage efforts on the federal lands have been drawn out under litigation, two recent salvage efforts on federal lands underscore recognition of the timely value of salvage to reduce fuel loadings following disturbance. One, the Tornado Salvage (2002) on the Mark Twain National Forest (Missouri) prompted agency officials to use the alternative arrangements procedures under NEPA with salvage operations starting in less than 4 months (USDA Forest Service 2002). In another, the court agreed with the agency of the critical need to remove firekilled timber before it lost the value to cover the cost of reducing fuel loads following the Rodeo- * The 29 th Council on Forest Engineering Conference. Coeur d Alene, Idaho, July 30-August 2,. W. Chung and H.S. Han, editors. pp

2 Chediski Fire (Forest Conservation Council vs. Forest Service, US District Court 2004). Recent action in Congress (House Bill 4200) indicates that legislators have also recognized the value of more rapid decision making after forest disturbance. With the change in management objectives on the federal lands in the United States, the purpose and value of salvage of fire-killed timber is being debated, particularly on those lands devoted primarily to maintenance of older forest wildlife habitat. The objective of this presentation is to present some background and context for active management following wildfire in the western United States and then conclude with Why, When and Where to salvage for accelerated forest restoration. Examples are drawn from southwest Oregon. 2. ISN T THIS WHAT NATURE INTENDED? Fire disturbance is an integral process in natural forest ecosystems in the western United States. Over the last decade or so about 750,000 acres burned annually in western forests. There is a growing perception that (1) active fire suppression has contributed to fuel buildup, (2) native American burning has been greatly reduced, (3) there has been a reduction in heavy grazing that previously reduced fine fuels, but contributed to fire suppression (no fine fuels to allow frequent, low intensity fires to reduce fuel and young trees creating future fuel ladders), (4) climate change may have contributed to increased forest growth as well as increased susceptibility of forests to insects, and (5) there is less habitat available for older forest dwelling wildlife then in earlier times. All five perceptions are supported by evidence. Improved access to the forest has reduced reaction time to wildfires, and smoke jumping and delivery of ever-improving aerial retardant have been very effective at initial attack. Native Americans certainly burn less acreage than previously, even on their own lands. Cattle and sheep grazing in the National Forests have been substantially reduced along with their consumption of fine fuels. In addition, selective harvesting of mature, fire-resistant trees earlier in this century, has changed the structure of our forest and with fire suppression has created shifts in species composition to more shade tolerant species. For example, Douglas-fir and true fir have crowded through pine and oak forests and in western rangeland ecosystems, juniper forests have expanded. Many public forests now carry more biomass than thought to be usual. And, few deny that there are fewer acres of older forests Much of the West is currently classified as being in a condition class that is outside its historic fire regime such that if fire occurs, the forest will burn with uncharacteristic effects (Schmidt et al. 2002). Areas that were previously thought to burn frequently at low intensity now will burn with high intensity with more frequent stand replacement events (e.g., Condition Class III). The science basis for stand structure modification to reduce the severity of fire effects is well recognized (USDA Forest Service 2004, Agee 2002, Agee and Skinner 2005) and forms much of the basis for the Healthy Forest Restoration Act of Post-fire analysis of some recent wildfires that spread into areas previously treated to reduce fuels show less severe fire effects to the site and overstory trees (e.g., the 2002 Cone Fire at the Blacks Mountain Experimental Forest in Northern California) (Skinner et al. 2005). 3. POST-FIRE RESTORATION

3 On private and state lands, specific recovery actions to salvage timber values and reestablish forests are fairly well laid out (see Oregon Forest Practice Act for example). The question of post-fire restoration on federal lands, however, has been hotly debated for the last years. With the change in management direction, land allocations in much of western federal forests are in some type of reserve status providing contributions to either aquatic or older forest wildlife habitat. Some land allocations have been made using prescriptive rules such as minimum distances to stream, while others often appear to have large green trees as the common denominator. When stand terminating fire comes to federal forests, what are the restoration options? An obvious place to start is to ask what are the goals and forest allocation for a given area? If the areas were prized for their large green trees for wildlife and aquatic contributions, have their functions now changed? Some might argue that their function has changed, and that their pathway now should be to provide young, naturally occurring early seral stage forest with an eventual return to mature forest. Others would argue that, if fish and wildlife habitat associated with complex forest condition was important, then what are the options for hastening the return of complex forest and does timber salvage have an appropriate role? 4. THE CASE FOR HASTENING THE RETURN OF COMPLEX FOREST WITH ACTIVE MANAGEMENT Decades of experience on lands managed for timber production have shown that active management can reliably re-establish conifer forests and that control of competing vegetation early on and thinning young stands can accelerate conifer diameter and height growth. Salvage of fire-killed trees can provide revenue and make future silvicultural activities safe and efficient. Is this experience relevant for restoring forests on lands not allocated to timber production? The existence of large green trees was the basis of identifying many reserves for older forest wildlife habitat. After stand-terminating crown fire in these forests, wildlife biologists point to the habitat value of fire-killed forests as providing the standing dead wood needed to provide snags until the new forest can provide new snags. What is the evidence? Everett et al. (1999) in a survey of 26 fires that occurred over a 100 year period in eastern Washington concluded that snags from the fire killed forest would not stand until new snags from the naturally regenerated forest could take their place. In other words, there would be a time gap during which soft snags were not available. They suggested reducing the time to new snags by (1) planting, (2) growth enhancing stand treatments, and (3) inducing mortality for some of the quickly regenerated trees to create new snags. There is significant evidence elsewhere that natural conifer regeneration in some ecological settings is a prolonged process that can delay the return of the regenerated conifer forest. Agee (1991) concluded that after stand replacing fire in SW Oregon Douglas-fir /hardwood forests the initial colonization phase by Douglas-fir can take decades in the face of competing vegetation. Thornburgh (1982) suggested that on tanoak sites in SW Oregon, if the Douglas-fir is immediately successful, the hardwoods develop under its canopy in a codominant role. If not, Douglas-fir eventually slowly emerges through the canopy. Agee and Thornburgh s observations are supported by recent work by Shatford and Hibbs () and Newton and Cole (2xxx).

4 In a survey of 11 fires in SW Oregon and northern California, Shatford and Hibbs () found that natural conifer regeneration establishment continued for years, with most of that occurring in the first 6-10 years, after fire and that 20 years after fire, the average height of the saplings was about 13 feet (5-23 ft) and were frequently overtopped by hardwoods and shrubs. They could not conclude that the site would eventually be dominated by conifers. Newton and Cole (2xxx), in similar areas in SW Oregon, reported from 22-year experiments of planted conifers under various intensities of brush control that average height varied from 30 feet with no brush control to 40 feet with brush control, with tallest individuals with and without brush control at about 52 ft. Thus, conifer height with immediate planting without brush control was more than twice that of natural regeneration seeding in after fire and with brush control it was more than three times that of natural regeneration. In fire-prone forests, the ability of a tree, such as Douglas-fir or ponderosa pine, to survive a future fire of a given flame length depends on (1) bark thickness, and (2) height to the live crown. The faster the conifer can be grown and the greater its diameter, the greater the opportunity to reduce its window of vulnerability from fire. Newton (2xxx) projects average height of the planted stand at 50 years to vary from ft depending on brush control. To reach even 71 ft the naturally regenerated stand, projected from the data by Shatford and Hibbs at an average growth rate of 13 ft per 20 years, will take 110 years to reach the same height, or in other words, an additional 60 years. These comparisons are rough, but the trends are clear. Accelerated height growth provides the opportunity for either manual pruning or pruning using prescribed fire. If conifers are buried under brush there is little chance they will survive a fire as compared to conifers above the brush and hardwoods. Both manual pruning and prescribed fire are costly investments that salvage can help to offset. In areas that are not allocated to timber production, reforestation does not have to follow the timber production model of planting 300 to 400 trees per acre on a fixed spacing. Instead, wide and variable spacing of trees (with vegetation control) can create a diverse forest structure (USDA Forest Service 2004b). Areas to be reforested in this way can be thoughtfully chosen. If the goal is to accelerate large diameter conifers for spotted owls, for example, wildlife biologists know that spotted owls prefer certain areas of the landscape. These areas could be targeted for reforestation and areas between these blocks could be allowed to go through an extended brush/conifer regeneration development, thus providing a diverse landscape. It is clear, though, for most western conifers, that if you want large trees quickly, you need to plant and you need to control competing vegetation. Subsequent thinning will allow trees to accelerate diameter growth to promote mature forest conditions. 5. SALVAGE AND FUEL LOADINGS Some have speculated that fuel loadings in the short and longer term would be lower if snags are left to aerially decay (Donato et al. ) over a long period of time rather than to remove some of fire-killed trees and manage the remaining slash through some combination of broadcast burning, piling and burning, or lop and scatter. Is there evidence that aerial decay results in faster decay than ground contact? The speculated superiority of aerial decay is not supported by the Fire and Fuel Extension (FFE) to the Forest Vegetation Simulator (FVS) (Reinhardt and Crookston, 2003). Using the default

5 values for the Southern Oregon variant, a 20-inch dbh Douglas-fir snag requires an average of 42 years to transition from a hard snag to a soft snag accompanied by a 20% reduction in density through decay. If that snag had been laying in contact with the ground, its expected reduction in mass is 1.5% annually or about 47% loss in mass during the same period (42 years), a much faster rate of decay. However, FFE projects that 95% of the 20-inch dbh Douglas-fir snags will have fallen in 35 years, so it is a moot point. The snags will fall to the ground. The management question is how quickly, and to what purpose. 6. WHY SALVAGE? Prompt salvage can have a number of positive effects in hastening the return of conifer forests: 1) Salvage provides immediate income to finance restoration activities, including site preparation, planting, and later follow-up treatments. Restoration is expensive. The rapid return of the conifer forest may require $ per acre investment over the first 20 years of the new stand. This is in addition to the $300-$1500 per acre for the initial fire suppression. 2) Salvage reduces the total amount of deadwood on the site, reducing potential for soil productivity loss and reducing future resistance to fire control if fire should return in the longer term. Some down wood is desirable for soil protection and wildlife, but excessive amounts can lead to severe soil impacts if consumed by subsequent fire. (Debano et al. 1998) 3) Salvage creates a safe work place for silvicultural activities and future fire suppression activities. Manual release, aerial herbicide applications, and fire trail construction are all made safer through judicious location of snag retention. 4) Salvage can be used to increase down wood in the short term in areas deficient in down wood. An example is the Biscuit EIS (USDA Forest Service, 2004b) which required additional down wood to be added during salvage depending upon plant association, topographic aspect, and fire intensity. This would have immediate benefits for watersheds. Woody debris slows water movement over land and creates small check dams to trap overland sediment movement following fire and longer term for wildlife requiring down wood structure. 5) Salvage can, if substantial, reduce consumer prices for wood products. On the other hand salvage, if substantial, reduces local stumpage prices (Prestemon et al. ). The primary revenue losers are tree growers, industrial and non-industrial, whose green trees must wait until fire-killed trees are processed. Primary revenue winners, in the short run, are owners of merchantable fire-killed trees and in cases where receipts are shared with local government, local government also benefits. 6) Salvage has the potential to contribute to carbon sequestration. Standing snags can be converted into longer term carbon storage. Accelerated conifer restoration can build new carbon stocks. And delayed cutting of growing green trees through substitution of fire-killed trees permits additional carbon capture.

6 7) Snags, however beneficial to wildlife, can add to fire risk. Although lightning prefers the higher conductivity of a green tree, a disproportionate number of wildfires are reported to start in snags (BC Forest Service ). Burning snags can spot embers, as well as roll downhill spreading fire. A carefully prepared snag retention plan retains snags in defensible locations. 7. WHERE TO SALVAGE? Snag retention prescriptions often are presented in terms of snags per unit area in different size classes. An efficient snag retention policy is one that retains snags considering current and future worker safety, value recovery, and snag persistence for wildlife habitat. From the point of view of snag persistence, the larger the diameter and more decay resistant the species, the longer the snag will be available for wildlife (Everett et al. 1999). Considering wood input to streams, the closer to the stream the more likely the contribution to riparian habitat. From an operations point of view, logging costs, in general, will be lowest when the yarding distance is shortest. There are two general snag retention patterns: dispersed and aggregated snag retention. This suggests: 1) Aggregating snags away from roads or landings. This makes future silvicultural treatments safe and efficient and creates defensible areas for future fire suppression as well as reducing yarding distances. 2) For cable logging, aggregating snags at long lateral yarding distances. This retains snags which would have had the highest yarding cost and lowest net value. 3) Aggregating snags in wide riparian zones. 4) Aggregating snags in steep areas, shallow soils, and other sensitive locations. 5) Aggregating snags in areas requiring the largest total road building plus yarding cost. 6) In areas of dispersed or aggregated retention consider rapid salvage of the smaller diameter snags and species with highest decay rates. These snags will persist the shortest time. For example, in some areas of the Biscuit Fire recovery plan, snag retention was implemented using wide riparian zones and aggregated snag retention on 50% of each 100 acres to meet 50% snag retention at the landscape level. 8. WHEN TO SALVAGE? As soon as possible for several reasons: 1) Salvage value decreases with time. How fast it decreases is affected by yarding system, yarding distance, species, and tree size (Akay et al. ). The faster the salvage, the lower the reduction in wood quality.

7 2) The faster the salvage the sooner planting can take place, at the lowest costs, and the lower the competition from grasses, shrubs, and hardwoods. Delays make planting and weed control much more expensive. 3) Prompt salvage reduces mortality in natural regeneration (Roy 1956). Ideally salvage would be completed before the following spring, but with large fires this may not be possible. But effectively targeting spots on the landscape can help managers focus salvage efforts in specific areas. 4) An exception to prompt salvage could be for trapping insects during specific parts of their breeding cycle. 5) Prompt salvage provides more snag retention options (both ecologically and economically) because early on even the smaller trees have value, which places less economic pressure for selecting the larger snags to cover the costs of the operation resulting in additional surplus funds for restoration activities. 9. LITERATURE CITED Agee, J Fire history along an elevational gradient in the Siskiyou Mountains, Oregon. Northwest Sci. 65: Agee, J The fallacy of passive management: managing for firesafe forest reserves. Conserv. Biol. Practice 3(1): Agee, J., and C.N. Skinner Basic principles of forest fuels management. Forest Ecology and Management 211: Akay, A., J. Sessions, P Bettinger, R. Toupin, and A. Eklund. Evaluating the salvage value of fire-killed timber by helicopter: effects of yarding distance and time since fire. West. J. Apple. For 21(2): BC Forest Service. The Forest Fire: A basic guide to fire behavior and suppression. British Columbia Ministry of Forests and Range, Protection Branch, Last accessed June 14,. DeBano, L., D. Neary, and P. Ffolliott Fire s effects on ecosystems. John Wiley and Sons. 333 p. Donato, D., J. Fontaine, J. Campbell, W. Robinson, J. Kauffman, and B. Law.. Postwildfire logging hinders regeneration and increases fire risk. Science 311:352. Brown, A. and K. Davis Forest fire control and use. McGraw-Hill. 686 p. Everett, R., J. Lehmkuhl, R. Schellhaas, P. Ohlson, D. Keenum, H. Riesterer, and Don Spurbeck Snag dynamics in a chronosequence of 26 wildfires on the east slope of the Cascade Range in Washington State, USA. International J. of Wildland Fire 9(4): Lyman, C.K Principles of fuel reduction for the Northern Rocky Mountain Region. Progress Report No. 1, Northern Rocky Mountain Range Experiment Station, Missoula, MT. 98 p. Newton, M and E. Cole. 2xxx. Manuscript in preparation. Data on file, Forest Science Department, Oregon State University. Ober, Richard Editor. "The Ultimate Clearcut." Forest Notes 174 (Fall): 3-7.

8 Prestemon, J., D. Wear, F. Stewart, and T. Holmes.. Wildfire, timber salvage, and the economics of expediency. Forest Policy and Economics 8() Reinhardt, E. and N. Crookston The Fire and Fuels Extension to the Forest Vegetation Simulator. Rocky Mtn. Res. Sta. General Tech. Report RMRS-GTR p. Roy, D Salvage logging may destroy Douglas-fir reproduction. USFS Calif. For. & Range Exp. Stn. Res. Note 107, Berkeley, CA. 5 p. Schmidt, K.M., J.P. Menakis, C.C. Hardy, W.J. Hann, and D.L. Bunnell Development of coarse-scale spatial data for wildland fire and fuel management. General Technical Report RMRS-GTR-87. USDA Forest Service, Rocky Mountain Research Station, Fort Collins, CO. 41 p + CD. Shatford, J., and D. Hibbs.. Predicting post-fire regeneration needs: spatial and temporal variation in natural regeneration in SW Oregon and N. California. Progress report: preliminary findings. Cooperative Forest Ecosystem Research notes (Feb ), Oregon State Univ., Corvallis. 5 p. Skinner, C.N., M.W. Ritchie, T. Hamilton, and J. Symons Effects of prescribed fire and thinning on wildfire severity: the Cone Fire, Blacks Mountain Experimental Forest. In: S.Cooper, editor. 25 th Annual Forest Vegetation Management Conference, January University California Cooperative Extension, Redding, CA. Thornburgh, D Succession in the mixed evergreen forests of northwestern California. In Means, J.(ed.) Forest succession and stand development research in the Northwest: pp Corvallis, Oregon State University, For. Res. Lab. US District Court Forest Conservation Council vs. Forest Service. Order No. 03-CV PCT-FJM. Fredrick J. Martone, Judge. Accessed from the WEB June 29, at USDA Forest Service Project Tornado Environmental Analysis Document. Mark Twain National Forest. 34 p. USDA Forest Service 2004a. R. Graham, S. McCaffrey, T. Jain (eds). Science basis for changing forest structure to modify wildfire behavior and severity. Gen. Tech. Report RMRS- GTR p. USDA Forest Service 2004b. Biscuit Fire Final Environmental Impact Statement, Appendix D (reforestation), Appendix G (deadwood management). Rogue-Siskiyou National Forests, Grants Pass, Oregon.