Forest Management Guide for Natural Disturbance Pattern Emulation
Contents |
Introduction
The “Forest Management Guide for Natural Disturbance Pattern Emulation” (NDPE) sets out new rules for planning and carrying out clearcuts, which account for almost 90 per cent of the total area harvested in Ontario. The Guide directs the forest industry to plan clearcuts in a range of sizes closer to the historical natural pattern of wildfires. In the boreal forest especially, this means that most of the area harvested will be in large clearcuts. Cut areas will include residual patches of forest and individual trees, however, to emulate landscape patterns created by fire. (A more detailed review appears in the Supplement to this report.)
The rationale of the Ministry of Natural Resources for this new approach is that the most reasonable course for sustaining forests and their biological diversity is to emulate the processes under which they have evolved. This is a relatively new concept in forest policy and is the subject of considerable study and evaluation in many jurisdictions in North America. It appears to be progressive forestry policy, but many information gaps remain. MNR acknowledges that there is uncertainty about the ability of the Guide to conserve biodiversity, and that most of the direction in the Guide represents new and untested approaches. (See Conserving Biodiversity in Ontario - 2002.)
Historically, the dominant natural disturbance in Ontario’s boreal forest was fire, which created large, even-aged stands of species such as black spruce and jack pine. MNR asserts that fire control measures have significantly reduced the number of wildfires and the total area burned in Ontario since the 1950s. The ministry also says that harvesting guidelines introduced in the 1980s to provide habitat for a few wildlife species have resulted in a checkerboard pattern of clearcuts smaller than historical fires. The ministry concludes that, in combination, these factors have resulted in forest fragmentation and negative impacts on biodiversity. MNR asserts that consolidating harvesting activities by making some larger cut patches on the landscape will result in larger patches of both disturbed and undisturbed forest, providing for the habitat needs of a broader array of forest wildlife.
The new Guide
Restrictions on size and distribution of clearcuts
There has been longstanding controversy over clearcut size in Ontario. Two rulings under the Environmental Assessment Act (EAA) influenced MNR’s development of this Guide. First, a condition of the 1994 approval of MNR’s timber management activities under the EAA was that clearcuts should normally be planned in a range of sizes up to 260 hectares, with exceptions above 260 ha allowed for biological and silvicultural reasons. The Environmental Assessment Board ordered MNR to implement the restriction and to develop standards for configuration and contiguity of clearcuts. Second, due to controversy in 1999 over large cuts planned in the Temagami area, the Minister of Environment and Energy ordered MNR to finalize the guidelines in 2001.
MNR’s finalized NDPE Guide restricts the number of cuts that may exceed 260 ha to 20 per cent in the boreal forest and 10 per cent in the Great Lakes-St. Lawrence forest. The Guide states that “MNR believes this is consistent with the EA Board’s direction that clearcuts should not routinely exceed 260 ha.” There is no upper limit on the size of the cuts exceeding 260 ha, so they are expected to account for most of the area cut in the boreal. MNR says that fires in the boreal can range in size up to hundreds of thousands of hectares, and the natural pattern is for a few large fires to consume about 95 per cent of the forest burned in any year. An early draft of the Guide said that although fires may be larger, 10,000 ha was the largest disturbance, or cluster of clearcuts considered practical. That proposed limit was removed from the final version of the Guide.
New clearcuts must be separated in time from older clearcuts long enough to allow vegetation in the old clearcut to reach 3 m in height or by 20 years, whichever is earlier. If this cannot be achieved, clearcuts should be separated by 100 m or more, determined during planning. These are the main restrictions on the size and distribution of clearcuts. The new standards intended to replicate some of the structural legacies of fire require the retention of internal patches and peninsular patches in each cut and 25 well-spaced individual trees per hectare. The Guide says that, generally, the identification of internal patches will be made during operations.
Estimates of historical natural disturbances
Each five-year forest management plan prepared by a licence holder for their local forest management unit must be prepared using an estimate of the historical natural disturbance for that forest. MNR says that the period 1921 to 1950 provides the best available data to represent the “natural” disturbance regime in Ontario. The Guide says that data for an earlier time period, if available for a forest management unit, could show different fire frequencies and extent.
Estimating the “average” fire frequency and size is an inexact science because of the enormous variability of fire, lack of data, and the different assumptions and methods that may be used. Forest management plans must also include forest composition objectives and age class structure objectives that move toward the estimated natural forest condition. A benchmark forest condition must be established for each forest management unit, usually in consideration of a larger ecoregional context. This is an improvement over past forest management planning, but some of the guidance for developing these objectives is vague.
Public participation and EBR process
MNR put a great deal of effort into the public consultation process for the NDPE Guide, including posting two drafts of the Guide on the Environmental Registry for comment. The ministry admitted that they were not able to reach consensus on the Guide with stakeholders such as the environmental community and the forest industry. The ministry received almost 3,000 comments on the two postings, and only a few were supportive of the direction of the Guide. The majority of comments were form letters and petitions.
Many members of the public, environmental groups, and scientists predicted that larger cuts would amplify the negative impacts of clearcutting, and pointed to the many chemical and biological differences between fire and clearcutting. The ministry was criticized for reducing the complex dynamics of fire to its size and distribution and for minimizing or ignoring other equally important elements. MNR acknowledges that the application of the Guide will not mimic fire because harvesting is a mechanical process while fire is a chemical one. The Guide mentions some of the ways in which clearcutting differs from fire – for example, impacts on nutrient recycling, pathogen control, soil compaction and species regeneration – but offers little direction for addressing those differences.
The Guide says that “forest management activities should be modified to reflect more closely the structural/biological legacy that occurs post-fire,” but most of the direction is provided as guidelines for forest managers to consider, rather than as standards. These progressive measures include leaving living trees vs. dead trees; leaving downed woody debris on site to return nutrients to the soil; using prescribed burning as frequently as possible in order to simulate the fire process and promote rapid turnover of nutrients and regeneration; maintaining old growth and natural age class structures; and avoiding salvage logging after fires in some areas. Many of these practices have not been applied much in the past in Ontario, and it is unknown whether the Guide will increase their use.
Environmental, economic and social impacts
It is impossible to predict the environmental, economic or social impacts of the Guide. MNR commissioned a major study to evaluate the economic and ecological impacts of the existing guidelines and proposed new Guide on two case-study forest management units, using computer simulation and evaluation tools. Few clear findings applied to both units, except that application of the new Guide resulted in significantly fewer active roads. In one management unit, harvest increased substantially at the expense of marten habitat, but benefited moose habitat. In the other management unit, all harvesting scenarios (even the existing caribou guideline) resulted in a dramatic loss of caribou habitat. One generalization the study was able to make was that as the area and volume harvested increases, there is a corresponding decrease in the older conifer forest important for some wildlife species. The consultants concluded that the trade-offs between timber production and biodiversity depend on each particular forest and its characteristics.
Many commenters from the public expressed concern that the larger cuts represented a “timber grab” and would increase the amount of forest harvested. The forest industry, on the other hand, said they could not support the new guidelines, primarily because they were untested with respect to impacts on wood supply and cost. MNR stated in its media release and a summary of the Guide, however, that the amount of timber allocated to forest companies will not increase or decrease as a result of these new guidelines. MNR’s consultants concluded that it was not possible to make any “across the province” generalizations about wood supply. The Guide states that its impact on wood supply and costs will be monitored.
Other commenters objected to MNR’s suggestion that the NDPE Guide and the new caribou guidelines would benefit wildlife (see “Can Forestry and Woodland Caribou Coexist?", and the decision review in the Supplement on pages 184–189).
Conservation interests are concerned that the NDPE Guide places primacy on the large-scale disturbances over individual species’ habitat requirements. Forestry companies on the other hand asked for a clear and unequivocal statement in the NDPE Guide that the other guidelines would not have to be used in addition to this Guide. The relationship between the NDPE Guide and existing wildlife habitat guidelines for caribou, marten, moose and other species remains somewhat unclear.
The ministry is currently reviewing all of its forest management guides with the intention of consolidating them into six guides (see pages 149–157 in the Supplement). The plan is to replace the many existing wildlife guides and the NDPE with three guides that would be applied hierarchically. The first would provide guidance on landscape management goals, the second would provide stand-level guidance, and the third would provide site-specific guidance for values such as raptor nests. The ministry describes this as a “coarse filter / fine filter” approach. The NDPE Guide says it will act as the coarse filter by focusing on the emulation of natural disturbance patterns and the maintenance of a broad array of forest conditions, and that established fine filter guidelines could be used to identify site-specific habitat needs. The authors of the Guide wisely observe that because it has not been tested, formal, rigorous monitoring of the Guide’s effects on the habitat for featured species is required before the established guidelines are relaxed. But it also says that the allocation of the available harvest area according to the natural disturbance pattern should be adjusted to meet the needs of individual species only “if absolutely necessary to prevent significant habitat losses” (emphasis added). The ECO urges MNR to clarify that habitats of vulnerable, threatened and endangered species must always be protected, and to move quickly to implement the promised rigorous monitoring of the effects of the Guide on the featured species.
The NDPE Guide also acknowledges that, because fires still do occur, the harvest must be designed to complement, not replace, the historical natural fire size frequency distribution. The caribou guidelines say that fires of 40,000 to 60,000 ha still occur in the northwestern portion of the commercial forest area. Currently, the combined area of burned and harvested land is greater than the historical area burned, and Ontario’s boreal forests will continue to experience large fires. MNR’s consultants said that “if one excludes fire from planning the harvest levels may not be sustainable in the long run, since large fires will undoubtedly occur,” and that “when significant catastrophic fire occurs a new plan should be developed with harvest levels reduced accordingly.” MNR will need to ensure that the total amount of forest burned and harvested stays within a reasonable range of natural variation.
MNR says that fire suppression, combined with forest harvesting, has altered the species composition of the forests. In the boreal forest, stands of softwood species such as spruce and jack pine, which thrive after fire, are being replaced with hard- woods such as trembling aspen and balsam poplar, which are intolerant of both shade and fire. This shift has been well documented, and many credible audits and studies have suggested that clearcutting with inadequate regeneration efforts is the main cause of this species conversion in Ontario’s boreal forest. The ECO has seen no evidence that the ministry desires either to encourage or to curb this trend in boreal forest conversion. Indeed, the continued commitment to clearcutting large areas of the original forest seems to run a great risk that conversion will continue. MNR should address this issue immediately and incorporate any needed direction into the new Guide as standards. MNR needs to be much clearer about its long-term provincial and landscape-level targets for the forests, including tree species composition, age classes and wildlife species populations.
Most research and mapping of historical natural fire patterns have been carried out on a very large ecoregional scale. Ontario has been divided into site regions, based on climate, landform and vegetation pattern variation across the province. MNR’s analysis of forest fire history is classified by site region, also referred to in the Guide as ecoregions, providing templates for fire disturbance for each of the 10 site regions that fall within the area of commercial forestry. However, the Guide will be implemented instead at the local level during the development of forest management plans for each of the 55 forest management units, based on administrative units.
The authors of MNR’s commissioned report concluded, in fact, that they did not feel “that fire and other catastrophic events can be adequately addressed within a management unit allocation process.”
Many observers are concerned that this broad landscape approach is hard to reconcile with the allocation of allowable cut for each individual management unit. Commenters expressed some apprehension about allowing industry foresters to plan clearcut size in the interests of conserving biodiversity in the long term, since they have an incentive to maximize timber production. While every plan must be approved by MNR, considerable discretion is given to the forest industry on how they apply the NDPE Guide and other guidelines – for example, to set goals for the future forest conditions on each forest management unit. The ministry must ensure that the planned harvest, future forest composition and wildlife habitat availability for each unit is compatible with ecoregional goals. This kind of planning must happen on a very large spatial and temporal scale, spanning more than one forest management unit over more than one cycle of harvest and regrowth of the forest.
In response to industry’s concerns that the NDPE Guide had not been sufficiently tested and that implementation should be deferred until spatial planning tools are available, MNR said it “supports the continued development of spatial planning tools to the extent that available funding will allow.” The ministry must commit to the development and distribution of spatial planning tools capable of applying the landscape-level direction within the guidelines. MNR must also be adequately funded to collect data and develop the necessary spatially based modelling and decision support tools.
ECO Comment
The ECO urges MNR to oversee the Guide’s implementation closely – to provide industry with the tools that will allow them to estimate the historical disturbance regime and to plan the new harvest patterns, and at the same time, be able to take into account the long-term and landscape-scale impacts on wildlife, on other users of the forest, and on future forest composition. MNR says that if monitoring or feedback from those using the Guide suggests that there are significant and unmanageable economic, ecological or social impacts, consideration will be given to a review and possible revision of the Guide before the normal five-year review. This is a good example of adaptive management. The ECO is concerned, however, that the Guide does not provide any detail on who will be responsible for the research and rigorous monitoring, nor how it will be carried out.
Ontario is one of the first jurisdictions to attempt to implement this new approach, although many other jurisdictions are moving in the same direction. Emulating natural disturbances appears to be a progressive approach to forest management, but it is a massive experiment on public lands. It is imperative that MNR be able to demonstrate to the public that this approach is scientifically sound and effective in conserving biodiversity.
This will continue to be a controversial issue. An application for investigation of this Guide and the size of recent clearcuts was received after the end of our reporting year. We will report on it in next year’s annual report.
| Recommendation 6:
The ECO recommends that the Ministry of Natural Resources immediately develop a rigorous monitoring and research program and the necessary computer-based mapping and decision-support tools for planning forest harvesting. |
| This is an article from the 2001/02 Annual Report to the Legislature from the Environmental Commissioner of Ontario. |
Citing This Article
Environmental Commissioner of Ontario. 2002. "MNR's Guide for Forest Harvesting." Developing Sustainability, ECO Annual Report, 2001-02. Toronto, ON : Environmental Commissioner of Ontario. 50-53.
