OBJECTIVE: Provide research support for formulation of management plans that incorporate the positive ecological role of bark beetle disturbance while protecting valuable forest resources.
Field studies and empirical approaches. Previous Project research has resulted in effective ways to protect individual stands from beetle attack for short periods of time, primarily through aggressive silvicultural manipulation (thinning).
This capability is an effective management tool for protecting specific resources, for example, designing timber harvest schedules. However, additional research is needed to more fully explain, quantify, and predict the effects of specific vegetation management practices on mountain pine beetle ecology and subsequent outbreak potential. For example, it is unclear what effects thinning has on bark beetle pheromone communication. More research is needed on the mechanism of pheromone/kairomone interactions that lead to switching from a focus to adjacent trees, and how the physical environment impacts switching behavior. We need the capability to relate stand structure, attributes of the physical environment, and beetle response to pheromone and kairomone plumes. Additional information is needed on how beetles respond to these plumes. We are actively involved in field research designed to answer these questions. The approach we are using involves pheromone manipulation used to focus attacks in particular areas, and then intensive monitoring of beetle behavior as the attack sequence progresses.
Effects of vegetation management on beetle behavior is only part of the equation, an equally important question is the long-term effects of these approaches on forest vegetation. Important questions need to be addressed regarding the long-term effects of forest management activities, including silvicultural prescriptions, on stand structure and integrity. In other words, what type and intensity of management activities can the ecosystem sustain and remain intact? In order to address this question we need to identify areas in which we can evaluate the long-term effects of vegetative manipulation. In the past, areas allowing us to perform the necessary manipulations have been actively managed for values (timber) incompatible with long-term research. A top priority is to identify areas where we can do such long-term projects.
The ultimate objective of research on vegetation management is to evolve capabilities for spatial risk assessment and prescription. This differs from current disturbance management in that the objective is not to directly manipulate entire landscapes, but is rather to modify the spatial structure of landscapes in such a way that the trajectory of outbreak patterns is toward a defined, "healthy" domain of attraction.
We are currently conducting applied research that uses existing technologies to achieve new management objective. For example, a "push-pull" strategy utilizing pheromones to target beetle attacks was applied in the Sawtooth National Recreation Area to help more effectively manage fuel-wood harvest. Another example is the application of silvicultural and pheromone strategies to manage spruce beetle populations on the Utah State University experimental forest. This latter project involves collaboration between our Research unit, two ranger districts, Forest Health Protection, and Utah State University.
Modeling and quantitative applications. Modeling applications for Problem 3 primarily result from the technology transfer of research models to management applications. As resource management objectives move from protecting individual stands for specific commodity values toward ecosystem management, the expanded spatial and temporal scales previously discussed will become necessary. For much the same reasons we are developing models as research tools, these same models (or modifications thereof) may provide valuable assistance to resource managers. However, not all models developed for research will find application in resource management. Models meet a variety of research needs, not all of which are important to resource managers. One effective way to evaluate the potential applicability of a model is through application in Technology Development Projects (TDP) funded through State and Private Forestry. Use of models in these technology transfer projects provides the opportunity for resource managers to evaluate the capabilities of a model without committing time and resources to its application. Then, if the model appears to fulfill a valid management application, it can be further developed to an operational stage. A good example of this approach is the TDP project on susceptibility/risk rating of southwest ponderosa pine. In this project, we are applying a between season, within bole model (MPBmod) to investigate the relationship between weather patterns and historical outbreak events. In doing so, collaborators from both Forest Health Management and the District level can evaluate the model. We envision much the same process with our spatial models. Collaboration with Forest Health Protection specialists provides the effective extension link between research and field application.
Not all modeling efforts result from application of research models. We need to be responsive to the identified needs of our customers. Development of a PC program (FINDIT) used to summarize stand insect and disease survey data is such an example. We have the expertise to develop such tools, particularly if they meet research needs as well as those of resource managers. Development of Decision Support Systems (DSS) is another potential quantitative area that we have expertise and interests in, however, we do not envision playing the lead role in developing such systems. Given current Project staffing and funding levels, our role should be development of basic models, then if validated models generate interest from resource managers, we should collaborate with other Forest Service Units (i.e. the Forest Health Technology Enterprise Team) in development of DSS. We also need to be aware of opportunities to take advantage of and/or expand upon related DSS technology. The spruce beetle DDS developed for Alaska is such an example. The framework for this system could readily be generalized to other bark beetles in other geographic regions.
Accomplishments planned for the next 5 years:
Goal: Provide the technical tools necessary for combining the predictive capabilities of Problem 1 with the ecological knowledge of Problem 2 to allow effective forest planning with respect to bark beetle disturbances.
(1) Develope validated spatial models of contagion (switching) between trees. (Appendix I: T1)
(2) Initiate long-term studies evaluating the effects of silvicultural treatment on stand dynamics.
(3) Formulate effective strategies for managing bark beetle populations to meet management goals.
Biology, Ecology and Mangement of Western Bark Beetles
Rocky Mountain Research Station and the USDA Forest Service, Logan Utah 84321
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