A Compilation of Restoration Science

Applying Ecological Principles to Management of the U.S. National Forests

SUMMARY

The U.S. National Forest System is a diverse and unique resource that must be managed within the context of competing and shifting social expectations. The policies under which the system operates have changed over the century, along with the values society places on wood production, wilderness protection, recreation, and biodiversity conservation. Proposals for major changes in the management of the National Forests are once again being debated. The consensus among forest ecologists is that all forests, despite their complexity and variability, should be managed as ecosystems. Sustainable forest management practices must be based on an understanding of how natural forest ecosystems work. We have identified major ecological considerations that should be incorporated in sound forest management policy and their potential impacts on current practice:

• Maintenance of soil quality and nutrient stocks that hold the key to current and future forest productivity may necessitate adjusting timber harvest rates and leaving more large woody debris on cutover sites.
• Protection of water quality and yield and prevention of flooding and landslides call for greater attention to the negative impacts of logging roads and the value of undisturbed buffer zones along streams and rivers.
• Conservation of forest biodiversity will often require reducing forest fragmentation by clearcuts and roads, avoiding harvest in vulnerable areas such as hardwood or old growth stands and riparian zones, and restoring natural structural complexity to cutover sites.
• Planning at the landscape level is needed to address ecological concerns such as biodiversity, water flows, and forest fragmentation. Repeated overcutting of National Forests lands in the past has been linked to lack of planning at the landscape scale.
• Increasing pressures on forests due to human population growth and global change oblige land managers to be alert for climate-related stresses as well as damage from ground-level ozone, acid rain, and acidification of soils and watersheds. This panel also analyzed the ecological assumptions, both explicit and implicit, that underlie a number of current proposals for changes in National Forest management. Key assumptions in some of these proposals are unsupported or directly contradicted by current knowledge of forest ecology. We are confident that:
• Despite natural disturbance and successional change, forest reserves are much more likely to sustain the full biological diversity of forests than lands managed primarily for timber production.
• No evidence supports the view that natural forests or reserves are more vulnerable to disturbances such as wildfire, windthrow, and pests than intensively managed forests. Indeed, there is evidence natural systems may be more resistant in many cases.
• Traditional beliefs that timber harvesting can duplicate and fully substitute for the ecological effects of natural disturbance are incorrect, although newer techniques such as retaining trees and large woody debris on harvest sites can more closely mimic natural processes.
• There is no scientific basis for asserting that silvicultural practices can create forests that are ecologically equivalent to natural old-growth forests, although we can certainly use our understanding of forest ecology to help restore managed forests to more natural conditions.
• Proposals to ban all timber harvesting on National Forests would leave managers without a valuable tool that can be used selectively to restore early successional habitat, reduce fuel loads, and contain pest and pathogen outbreaks in some forests. Creativity is needed in designing forest management policies for the future, but simple solutions are almost never adequate for sustaining a complex system that must fulfill diverse expectations. Sustainable management policies must make full use of current ecological knowledge. The goal of our policy efforts today should be to design forest manage- ment practices that assure the value of our forest resources for future generations.

CAN LOGGING RESTORE OUR FORESTS - WHAT DOES THE SCIENCE SAY?

Timber harvest may increase insect activity and productivity and associated mortality to trees.

Timber harvest will remove dead and dying material from the site and inhibit the recruitment of downed woody material as time progresses. Timber harvest and associated r educed structural complexity and reduced age and size class diversity are all known to reduce population abundance and diversity of ants and a number of birds. For instance, ants are documented to require downed woody material in a variety of sizes and in all stages of decomposition (Torgersen and Bull, 1995). This is an attribute that is negatively correlated with harvest of the dead and dying trees and positively correlated with natural succession, especially after disturbance. Ants and birds are known to predate on insect species which cause mortality to trees, serving as a potentially important population control in the case of epidemics or before they occur (Campbell, Torgersen and Srivastava, 1983). Structural and functional characteristics associated with unlogged forests are also important for canopy arthropods, which play an important role in regulating pest outbreaks (Schowalter, 1989).

Structural complexity, functional diversity, diversity of ecological process and diversity of structure in roadless areas are all expected to be less susceptible to the outbreak of pests and regulate insect activity in surrounding homogenized forests (Schowalter and Means, 1989; Franklin, Perry, Schowalter, Harmon, McKee and Spies, 1989).

A large body of scientific evidence also indicates that increased edge effect and increased sunlight into stands, resulting from reduced canopy cover associated with timber harvest, can directly promote the population abundance, productivity and persistence of insects which cause mortality to trees of (Roland, 1993; Rothman and Roland, 1998; Kouki, McCullough and Marshall, 1997; Bellinger, Ravlin and McManus, 1989).

Establishing Historical Range of Conditions. Before restoration can occur on the logged lands, a more accurate assessment of the historic conditions must be made. The Interior Columbia Basin Ecosystem Project cites Hann, Jones, Karl, et al 1997 and gives a general discussion of succession and the disruptions by a century of Forest Service/BLM management in the interior Columbia basin, but implies a pre-settlement condition in forested stands such as the following statement (pg. 2-60, SDEIS) "... the open late seral single story forests changed to relatively dense late seral multi-story forests ..." While this may be the case in areas that have been heavily logged, we don't believe this is generally accurate, and that the maps of changes in fire regime severity (pgs. 2-54 to 2-57) are based on unfounded assumptions.

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A current example is the Olmstead timber sale, Prairie City Ranger District, Malheur National Forest. Here, much of the project is designed to create a single-stratum with large tree development, over one third of the entire project area is proposed for heavy thinning (Olmstead EA, Purpose of and Need for Action, April 26, 2000). Yet, 1924 photo points from the Skovlin/Thomas report (1995) pages 70-71, clearly show a thick stand at the edge of Lyman and Olmstead meadows, both in or near the project area.

The Douglas Fir beetle project in NE Washington and N. Idaho tells the same story. The FEIS discusses the need to log to increase resiliency to fire and insects, the prescription is stand conversion to a much lower basal area, yet the Lieberg report show pictures of this area over a hundred years ago as a thick stand of trees.

Every timber sale in the past few years in the interior West has claimed a need to return conditions to a "pre-settlement" status. We question the authenticity of this model and cite two references that seem to refute the idea that our forests were far more open. The John Lieberg reports,1897-9, part of the US Geological Surveys of the 1890's indicate stand densities, species by type and size, and contain photographs and descriptions of forest reserves in North Idaho, including the Priest River, Bitterroot and Coeur d'Alene areas. They clearly show high stem densities, many snags and burnt areas and few open stands. The Skovlin and Thomas report Interpreting Long-Term Trends in Blue Mountain Ecosystems from Repeat Photography, Pacific Northwest Research Station PNW GTR-315, June 1995, shows many photos from 60-80 years ago with stands that are very dense, as well as many stands that appear to be recently burned. In the case of both the USGS, John Lieberg reports and the Blue Mountain report there is little evidence of the widely spaced forest that current Forest Service timber sales are trying to attain. We believe the bias toward logging has corrupted forest managment and that an honest appraisal of stand succession, historic processes and desired future condition must be made.

Logging may spread insects and disease. At a staff meeting on October 6, 1998, in North Idaho, plans for the Douglas Fir Bark Beetle timber were discussed. One staff person stated "Seems to be a lot of the kill is in the areas that we actively manage", while another remarked that "I think our treatment could have an impact as well, especially if we're talking about regeneration harvest."

On the Okanogan National Forest, the Forest Service had plans to log the Long Draw roadless area, David Greenwald stated the following in his paper, An evaluation of the Long Draw Salvage Timber Sale Using Fire Behavior and Effects Models, written in 1996:

"In conclusion, it is my opinion based on reading the literature and on this modeling exercise that there is no forest health crisis in the Long Draw area and salvage logging does little to nothing to increase the long-term resilience of these forests to stand destroying fires or insect outbreaks."

With regards to the spread of insects and disease, the following is from the Fish Bate Timber Sale analysis file, Lolo National Forest, Idaho/Montana, page 152:

Repeated intermediate harvests, partial harvesting, or uneven-age management, such as economic selection cutting or sanitation/salvage cutting could increase both the frequency and severity of root diseases in stands. Even one harvest entry in stands has been found to greatly increase the frequency of root disease compared with stands that have not had tree harvest entries. Studies have shown a doubling of root disease frequency in stands on the Lolo National Forest in Montana with at least one harvest entry compared to those with no history of tree harvest.

Logging Increases Fire Risk. The Sierra Nevada Ecosystem Project summary states that, "more than any other human activity, logging has increased the risk and severity of fires by removing the cooling shade of trees and leaving flammable debris." (Status of the Sierra Nevada, Vol. 1., Assessment of Summaries and Management Strategies, pg. 62. Sierra Nevada Ecosystem Project; "As a by-product of clearcutting, thinning, and other tree-removal activities, activity fuels create both short- and long-term fire hazards to ecosystems...Even though these hazards (with logging slash) diminish, their influence on fire behavior can linger for up to 30 years in the dry forest ecosystems of eastern Washington and Oregon.". (M.H. Huff and others, 1995. U.S. Forest Service).

"Fires in unroaded areas are not as severe as in roaded areas because of less surface fuel... Many of the fires in the unroaded areas produce a forest structure that is consistent with the fire regime, while the fires in the roaded areas commonly produce a forest structure that is not in sync with the fire regime. Fires in the roaded areas are more intense, due to drier conditions, wind zones on the foothill/valley interface, high surface-fuel loading, and dense stands".

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Logging Isn't Needed on Our National Forests. A recent scientific review team, led by Wenatchee Forest Service Research Station Scientists Paul Hessburg and John Lemkuhl, has found that on dry sites (which include much of the intermountain west), the use of prescribed fire alone would restore tree stocking levels and can be implemented on a broad range of cases without prior thinning.. Science Peer-Review Summary of the Wenatchee National forest's Dry Forest Strategy, June 1999.

The available evidence indicates that logging operations, even when carefully conducted, can result in numerous adverse environmental impacts, including:

• damage to soil integrity through increased erosion, compaction, and loss of litter layer (Harvey et al. 1994, Meurisse & Geist 1994).
• increased mortality of residual trees due to pathogens and mechanical damage to boles and roots (Hagle & Schmitz 1993, Filip 1994)
• creation of sediment that may eventually be delivered to streams (Beschta 1978, Grant & Wolff 1991)
• increased levels of fine fuels and near-term fire hazard (Fahnestock 1968, Weatherspoon 1996, Wilson & Dell 1971, Huff et al. 1995)
• dependence on roads, resulting in numerous adverse effects (Henjum et al. 1994, Megahan et al. 1994)
• reduced habitat quality for sensitive species associate