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Pest-specific inventories require substantial resources and are often infeasible, creating a need for alternative means of early pest detection. We examined the potential for stand inventories to detect forest health threats by using a unique dataset of mapped eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck.) infestations in black spruce (Picea mariana Mill. B.S.P) stands of northern Minnesota, USA. We simulated stand inventories across a range of sampling intensities; that is, current standard (S) methods in Minnesota, adding one plot (S + 1), doubling the intensity (2S), and halving the intensity (S/2), using fixed-radius plots and transect buffers for detection. We categorized stands into low, moderate, and high infestation severity. We simulated detection at multiple viewing distances along S inventory transects in low severity infestation stands. Detection probability increased as sampling intensity increased. Plot-based detection averaged > 50% for moderate and high severity infestations except S/2 in moderate severity infestations. Notably, transect-based detection averaged ≥ 85% at viewing distances of 25 to 100 m. Results suggest stand inventories could provide opportunities to detect forest health threats with unique signatures when transect observations are included. Thus, forest health specialists may consider including pest-specific training for foresters in current inventory methods, requiring modest investment of time and effort.

Multiple ecological, economic, social, and political facets influence forest-planning decisions. Decision models have been widely used in forest management planning, but most are deterministic models. However, long-term forest planning problems are surrounded by potential uncertainties. To begin to account for uncertainty surrounding growth and yield under climate change conditions, a stochastic forest planning model was developed and tested. The intent of the model is to help identify potential current forest management actions that will perform well over a range of plausible climate change scenarios (futures). The stages of the model address how uncertainty about the future might unfold, with model solutions providing immediate management actions plus detailed contingency (recourse) plans for each future. The use of specialized decomposition methods of operations research has allowed for testing the model in a detailed and large application. Results from the case study showed that planning for an average deterministic case produces a misleading solution, underestimating the potential impact of climate change. On the other hand, only planning for a worst-case scenario ignores the potential value of management opportunities under other likely futures in which harvesting benefits could be greater. Overall, results advance our understanding of recognizing forest-wide uncertainty in forest management planning models. Study Implications Stand-level decisions often have forest-wide implications. Forest planning helps coordinate management of stands to address ecological, economic, and social aspects. Decision models are often used, but most assume all the information is known. However, long-term forest planning is surrounded by potential uncertainties, such as climate change. We developed a model to identify current forest management actions that will perform well over a range of plausible climate change scenarios instead of just one. The novelty lies in how we solve the problem. Breaking it into smaller subproblems allows us to include more stand-level details while still tackling a large problem.

Innovation and knowledge exchange are critical to foster adaptive management and continual learning. Across the spectrum of knowledge exchange, ranging from peer-reviewed research to anecdotes, there is a largely untapped middle ground: real-world silvicultural case studies implemented and documented by foresters. The University of Minnesota Great Lakes Silviculture Library is a novel, freely available platform designed to enable foresters to exchange these case studies. Five years after its launch, we conducted focus groups with foresters from Minnesota and Wisconsin, USA, and Ontario, Canada, to explore the platform’s usage and value. Participants valued having access to examples of silvicultural treatments and their outcomes that they could easily digest, apply, and share. They gained new knowledge from management across administrative boundaries. They also appreciated the consistent, relatable case study format. However, participants noted that limited time was the primary barrier to wider authorship and readership. The Library enables information exchange across agencies and disciplines within natural resources, giving greater voice to practicing foresters and supplementing other sources of forestry knowledge.

Survival of planted seedlings following a regeneration harvest can be challenging and early interventions through silvicultural treatments may be required for successful stand establishment. We tested the influence of soil amendment (biochar plus compost, compost-only, or control) and vegetation control (VC; applied either initially or annually for five years using brush saws) on the growth and survival of jack pine at three sites in northern Minnesota. Application of the biochar plus compost soil amendment increased seedling survival by 30% relative to the control in the first year, but there was no significant difference in survival among soil amendment treatments after five years. Both soil amendments increased diameter growth relative to the control (14% increase with biochar plus compost, 10% increase with compost only), with most of the biochar plus compost effect attributed to the compost. Annual VC increased diameter growth by 17% relative to initial VC, but overall effects on survival and growth were generally small relative to reported effects of VC via herbicide. The limited short-term influence of biochar and manual VC on growth and survival of jack pine indicates that these practices are likely not an effective means to increase jack pine establishment, but other benefits (e.g., increased carbon storage) may become apparent with time.

Water table fluctuations in peatlands are closely coupled with the local climate setting and drive critical ecosystem processes such as nutrient cycling. In Minnesota, USA, peatlands cover ten percent of the surface area, approximately 2.5 million hectares, some of which are actively managed for forest products. To explore the relationship between peatland water tables and precipitation, long-term data (1961 to 2019) were used from the Marcell Experimental Forest in northern Minnesota. Starting in 1961, water table data from seven peatlands, including two types of peatlands (bogs and fens), were measured. We used the Theil-Sen estimator to test for monotonic trends in mean monthly water table elevations for individual peatlands and monthly precipitation. Water levels in bogs were both more variable and had mean water table elevations that were closer to the surface. Individual trends of water table elevations differed among peatlands. Water table elevations increased over time in three of the bogs studied and decreased over time in two of the bogs studied. Trends within fens were notably nonlinear across time. No significant linear trend was found for mean monthly precipitation between 1961 and 2019. These results highlight differences in peatlands types, local physiography, and the importance of understanding how changes in long-term dynamics coupled with changing current conditions will influence the effects of water table fluctuations on ecosystem services. The variability of water table elevations in bogs poses potential difficulties in modeling these ecosystems or creating adaptive management plans. KEYWORDS: Peatlands; Hydrology; Water tables; Bogs; Fens; Monitoring; Minnesota; Climate Change

Emerald ash borer (EAB) (Agrilus planipennis) has had an extensive impact across North America. It is currently present in Minnesota, USA but has not been observed in northern portions of the state where the vast majority of black ash (Fraxinus nigra) trees are located. Unlike other ash forest communities, the black ash forest type occurs in wetlands and is dominated by black ash with few associate species. Because of this, the loss of black ash can result in changes to the hydrological regime and species composition. The goal of this study was to quantify the structure and composition of regeneration 5 to 11 years post-harvest in three silvicultural systems (group selection, clearcut, and diameter-limit harvesting) to evaluate the potential for establishment of other tree species. Overall, regeneration post-harvest was high but variable across all systems. Across silvicultural systems, there was no significant relationships between residual overstory trees (> 10 cm dbh) basal area and non-ash regeneration TPH, indicating flexibility in designing treatments for diversification. Populus sapling (2.54–10 cm) density was significantly negatively correlated to the depth of the soil muck layer. In contrast, a positive relationship was observed between depth of the soil muck and black ash saplings. These findings indicate that specific silvicultural systems in combination with site quality (e.g., clearcuts on high-quality sites with shallow muck layers) may help to promote non-ash species in black ash forests that are threatened with EAB.

Silvicultural decisions and forest-management practices in Minnesota represent the collaboration and partnership between forest managers from multiple organizations and forest researchers. To better understand current practices, trends, needs, and opportunities, Minnesota has invested in the collection of quantitative data on the application of silvicultural systems and forest-management activities in 1991, 1996, 2008, and 2017. Drawing on those data, the goal of our study is to summarize 26 years of data to characterize and quantify trends in forest-management practices. During this period of time, timberland ownership (acres) has increased, whereas harvested volume has decreased (cords). Across state, federal, county, forest industry, and tribal forest lands, which collectively represent the majority of timberlands in Minnesota, the clearcut system decreased from 91% of the harvested area in 1991 to 72 percent in 2017. In contrast, the proportion of total harvested area as part of shelterwood, seed tree, selection, and thinning treatments all more than doubled from 1991 to 2017. Factors influencing the changes relate to forest health and diseases, shifts in ownership structure, and shifts in organizational policy and/or goals. The factors identified mirror many of the trends forest managers are experiencing in other regions, nationally and internationally.

The range of eastern larch beetle, Dendroctonus simplex LeConte, extends across northern Canada and the United States sympatric, with its host, eastern larch or tamarack Larix laricina (Du Roi) K. Koch. Eastern larch beetle has long been viewed as a nonaggressive bark beetle whose populations flare for short durations after periods of tree stress. Recent decades, however, have noted extended tree-killing behavior along the southern margin of the host's range in the Great Lakes region of North America that deviate strongly from historic patterns. This chapter examines the biology and life cycle of the eastern larch beetle and its impacts on tamarack forests in light of a changing climate. Impacts of warming temperatures and extended growing seasons are discussed as well as key areas of future research. The impacts of the eastern larch beetle on tamarack forests are likely to be amplified as climate warming continues.

White-tailed deer (Odocoileus virginiana Zimmermann) browsing reduces seedling and sapling abundance of more palatable winter woody browse such as Tsuga canadensis L. Carriere, Thuja occidentalis L., Betula alleghaniensis Britton, and Pinus strobus L. across the Lake States Region of the USA. White-tailed deer consume buds and twigs of tree seedlings and saplings as forage. Deer populations in the Lake States Region of the USA have increased over recent decades due to a decrease in predators and an increase in habitat fragmentation. Higher deer population densities present challenges to regeneration of tree species. The objective of this work was to quantify the effects of deer browsing on tree seedling and sapling abundance and species richness of woody tree species which vary in deer browse palatability. Deer browsing impact measurements from the tree regeneration indicator from the US Department of Agriculture Forest Service’s Forest Inventory and Analysis program were used to predict seedling and sapling abundance from overstory basal area and a deer browsing index in the Lake States Region. Overstory basal area was important in predicting seedling and sapling abundance for all species (p < 0.05). Deer browsing affected seedling and sapling abundance differently across species, with the most palatable species showing lower stocking or negligible effects with browse. Results support the importance of quantifying impacts of deer browsing for use in determining the survival and abundance of palatable species in the smallest size cohorts.

Forests and wood products, through the mechanisms of carbon sequestration and storage, can slow the rate of global climate change that results from greenhouse gas emissions. In recent years, both natural resource managers and the public have placed greater focus on the role of forests and wood products as a solution to help mitigate the effects of climate change. Little is known about the perceptions and viability of carbon sequestration and storage as a management goal for natural resource managers of public agencies. We explored these perceptions in Minnesota, USA. Minnesota has 7.2 million hectares of forest land managed by a diverse array of landowners, from public agencies (55% of forest land) to private (45%) owners. We sought to (1) understand natural resource managers’ and forest owners’ perspectives on forest carbon opportunities and (2) understand the feasibility of management strategies that could be implemented to increase forest carbon sequestration and storage at a state level. We conducted two focus groups with 15 mid- and upper-level natural resource managers and non-industrial private forest landowners, representing both rural and urban perspectives and a variety of agencies and organizations. Minnesota natural resource managers and non-industrial private forest landowners indicated that they thought managing forests for carbon was compatible with other management goals but nonetheless represented a trade-off. However, they viewed the carbon credit market as the “Wild West” and noted several barriers to entering the carbon market, such as inconsistent carbon accounting protocols and a lack of connection between the price of carbon credits and the cost of managing forest land for carbon sequestration and storage.

Across the boreal forest in North America, the black spruce (Picea mariana) cover type is ecologically and economically important, occupying roughly 10 percent of Minnesota’s, USA 17.4 million acres (7.0 million hectares) of forestland. Traditionally managed through clearcut regeneration harvests, alternative silvicultural systems are being increasingly used in Canada. Here, we examine the 10- and 57-year effects of six silvicultural treatments (clearcut strips, clearcut patches, thinning, group selection, single-tree selection, shelterwood) on stand structure and dynamics in lowland black spruce. Treatments were installed in 1948 in northern Minnesota, and remeasured and re-treated 10 years later. A subset of the clearcut strips, clearcut patches, and shelterwood treatments were remeasured in 2017. After 10 years, diameter growth of residual stems varied by treatment, with the shelterwood experiencing the greatest growth, and basal area increased in all but the shelterwood treatment. Over the long term, the shelterwood exhibited larger diameters and heights and greater crown ratios, basal area, structural complexity, and compositional diversity than the clearcuts. Our results suggest that managers may consider using a shelterwood instead of traditional large clearcuts to achieve increased structural and compositional diversity, particularly when eastern spruce dwarf mistletoe (Arceuthobium pusillum) does not necessitate a traditional clearcut. Study Implications: This research suggests that alternatives to traditional clearcutting of black spruce stands in the United States Lake States have merit and may be used by managers to achieve stands that supply additional options in the future. In stands of older ages where advance regeneration is already present, a shelterwood treatment provides a means to achieving sufficient regeneration without the use of aerial seeding while also resulting in future stands that have larger-diameter trees, greater basal area, increased structural complexity and compositional diversity, and potentially a shortened rotation age. Additionally, a shelterwood increases diameter growth on residuals to make overstory removal more economically feasible. Consideration should be given to the amount of residual growing space to reduce mortality because of wind events over the short-term, possibly by aggregating residuals.

White spruce (Picea glauca (Moench) Voss) plantations have historically been an important source of high-quality forest products in the Great Lakes Region of North America. Thinning in spruce plantations is a common silvicultural practice for reducing competition and promoting resiliency to forest health threats such as eastern spruce budworm (Choristoneura fumiferana Clemens), a native forest pest of eastern North America. Spruce budworm larvae feed on the foliage of trees, which reduces growth and potentially causes mortality during an outbreak. There has been continual spruce budworm defoliation in northern Minnesota, U.S.A., since the mid-1950s, with higher levels of defoliation in the late 1990s. This research modeled the diameter growth response of white spruce 18 years after initial thinning in stands that presently range between 44 and 64 years old. Some stands received a second thinning in recent years. We used generalized nonlinear least squares and nonlinear mixed-effects models to estimate annual diameter growth using common tree and stand metrics. Growth model performance was improved by including thinning and frequency of spruce budworm defoliation as modifiers of diameter growth. Results of this study highlight how thinning in combination with insect disturbance affect diameter growth in white spruce plantations of northern Minnesota.

Insects, fungi, and diseases play an important role in forest stand development and subsequently, forest management decisions and treatments. As these disturbance agents commonly occur within and across landscapes, modeling has often been used to inform forest planning and management decisions. However, models are rarely benchmarked, leaving questions about their utility. Here, we assessed the predictive performance of a Bayesian hierarchical model through on–the-ground sampling to explore what features of stand structure or composition may be important factors related to eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck) presence in lowland black spruce (Picea mariana (Mill.) B. S. P.). Twenty-five state-owned stands included in the predictive model were sampled during the 2019 and 2020 growing seasons. Within each stand, data related to the presence of eastern spruce dwarf mistletoe, stand structure, and species composition were collected. The model accurately predicted eastern spruce dwarf mistletoe occurrence for 13 of the 25 stands. The amount of living and dead black spruce basal area differed significantly based on model prediction and observed infestation, but trees per hectare, total living basal area, diameter at breast height, stand age, and species richness were not significantly different. Our results highlight the benefits of model benchmarking to improve model interpretation as well as to inform our understanding of forest health problems across diverse stand conditions.

Effective delivery of continuing education programs can improve their impact. Using the first of four two-week modules of a professional short course, we tested outcomes of a flipped classroom approach, comparing professional foresters’ completion rates, preference for, and perceived value of pre-module content delivered via video and reading. Participants in the National Advanced Silviculture Program self-reported significantly higher pre-module completion rates, preference for, and perceived value of video over reading. This simple study suggests the potential for video to serve as an accessible and preferred format for delivery of key content to supplement an in-person continuing education program.

Ash trees (Fraxinus spp.) are a prominent species in Minnesota forests, with an estimated 1.1 billion trees in the state, totaling approximately 8% of all trees. Ash trees are threatened by the invasive emerald ash borer (Agrilus planipennis Fairmaire), which typically results in close to 100% tree mortality within one to five years of infestation. A detailed, wall-to-wall map of ash presence is highly desirable for forest management and monitoring applications. We used Google Earth Engine to compile Landsat time series analysis, which provided unique information on phenologic patterns across the landscape to identify ash species. Topographic position information derived from lidar was added to improve spatial maps of ash abundance. These input data were combined to produce a classification map and identify the abundance of ash forests that exist in the state of Minnesota. Overall, 12,524 km2 of forestland was predicted to have greater than 10% probability of ash species present. The overall accuracy of the composite ash presence/absence map was 64% for all ash species and 72% for black ash, and classification accuracy increased with the length of the time series. Average height derived from lidar was the best model predictor for ash basal area (R2 = 0.40), which, on average, was estimated as 16.1 m2 ha−1. Information produced from this map will be useful for natural resource managers and planners in developing forest management strategies which account for the spatial distribution of ash on the landscape. The approach used in this analysis is easily transferable and broadly scalable to other regions threatened with forest health problems such as invasive insects.

The potential expansion of mountain pine beetle (Dendroctonus ponderosae Hopkins) from western North America into the Great Lakes Region (Michigan, Minnesota, Wisconsin, and Ontario) could negatively impact eastern pine forests. Currently, no metrics exist to assess susceptibility in the region. I have developed a hazard rating system for the Great Lakes Region that utilizes common attributes of forest structure and composition and have assessed the current susceptibility using the Forest Inventory and Analysis database. The vast majority of plots (∼90%) that contained at least one living pine species were classified as moderately or highly susceptible. Plots on federal (USDA Forest Service) lands had higher susceptibility ratings than those on private or state-owned lands. Ordination results highlighted differences among the susceptibility scores (high, moderate, and low) across plots. Plots with high susceptibility were associated with greater total plot density and pine density, and plots with low susceptibility were associated with lower total plot density and greater overstory species richness. There are still many unknowns regarding mountain pine beetle in the Great Lakes Region; however, as natural resource managers plan for the future, they may want to consider the potential arrival of mountain pine beetle in eastern pine forests when developing silvicultural prescriptions.

Disturbances play a fundamental role in shaping forest communities. It is therefore important to accurately quantify their frequency and magnitude in forest ecosystems. Tree-ring series are commonly used for relatively accurate detection of past disturbances. Currently, several dendroecological techniques exist that enable the detection of disturbances in tree-ring series. In this study, increment cores (n = 312) were collected from trees that were deliberately retained in harvested gaps of two natural-disturbance-based silvicultural systems in the Acadian Forest of Maine, USA. These systems were designed to approximate the gap-based natural disturbance regime of the region. Since the specific harvest dates and severities were known, we compared the efficacy of three predominant disturbance detection techniques in accurately detecting disturbance within two years of the harvest date across five common, yet ecologically distinct species -- Acer rubrum, Picea rubens, Pinus strobus, Thuja occidentalis, and Tsuga canadensis -- and the length of elapsed time prior to when maximum growth responses were experienced. We tested the growth-averaging method, the boundary-line method, and the combination of the growth-averaging and boundary-line methods (Splechtna method) using the TRADER R package. We found little variation among detection techniques in their -- relatively high success -- rate of detecting disturbance within two years of the harvest date (growth-averaging method: 69.9%, Splechtna method: 68.6%, and boundary-line method: 64.1%). We most frequently found negative correlations with pre-treatment growth rates and detection rates among detection techniques. Our estimates of disturbance severity did not influence the probability of detecting the year-of-harvest. Of the species tested, Tsuga canadensis (73.7% − 85.5%) and Thuja occidentalis (78.4% − 83.7%) had the greatest detection rates across the techniques while Pinus strobus was consistently the lowest (51%). Time-lags – defined as the number of years post-harvest before a tree reaches its peak growth rate – were also analyzed. Pre-disturbance basal area increment and crown ratio were marginally negatively correlated with the length of time-lags in response to harvest and Thuja occidentalis (7.2 ± 0.4) and Tsuga canadensis (6.8 ± 0.3) had significantly longer time-lags than Acer rubrum (5.4 ± 0.3). Overall, all techniques demonstrated relatively high detection rates (>60%), given the range of sizes and ages of the species tested and reduced two-year time window for detection. Absent from all models were variables that measured disturbance severity, which suggests tree responses to disturbance were more sensitive to tree-level attributes and local changes to the growing environment.

The aim is to help identify how spatial facets of forest management can be analyzed and better understood in strategic forest management planning. Focus is on stand-level spatial interdependencies potentially related to a wide range of considerations including wildlife habitat, invasive species, forest management regulations, and cost of harvest operations. Spatial facets addressed include adjacency and harvest area limitations, habitat connectivity, edge impacts, proximity considerations, and management options for restructuring stand shapes and sizes. Emphasis is on recent studies with direct connections to both forest management planning and problem structures of operations research. Models related to explicit spatial facets of forest management are increasing in number, size, and complexity. Specialized approaches have been developed that are tailored to spatial facets of forestry problems. Improvements have also been made in ways of solving existing spatial models. Uncertainty is also being addressed in applications, and most recent studies tend to address multiple forest objectives. Spatial interrelationships between stands are important considerations in forest planning. Operation research models can help explore the complex combinatorial nature of the situation. The need to better integrate multiple objectives over large landscapes is commonly suggested. Tradeoff analyses are important for decision makers to better understand forest-wide opportunities. New technology including parallel processing will help increase the practicality of model applications.

Bark beetle (Dendroctonus spp.) outbreaks in the middle latitudes of western North America cause large amounts of tree mortality, outstripping wildfire by an order of magnitude. While temperatures play an important, and direct role in the population dynamics of ectothermic bark beetles, an equally important influence is the nature of the host substrate—the structure and composition of forested communities. For many of the dominant tree species in the western United States, “hazard” indices have been developed for specific bark beetles, which generally include three key variables—host tree size, absolute or relative density of the stand, and percentage of host composition. We provide a conceptual model to apply these three variables across forest ecosystems and bark beetles that shifts the thinking from a species–specific model to a model which focuses on the underlying ecological factors related to bark beetle outbreak susceptibility. We explored the use of our model across multiple scales using the Forest Inventory and Analysis database: Interior West, USA, the states of Colorado and Arizona, and specific national forests within Arizona that are implementing a large-scale restoration effort. We demonstrated that across the Interior West and Colorado, the vast majority of forests have moderate to high susceptibility to bark beetles. Our conceptual model maintains the simplicity of previous “hazard” models but acknowledges the need to consider scale when managing bark beetles. It also shifts the management approach from resistance thinking to the development of “associational resilience”, where the focus is not on any one individual stand or area but the longer-term perspective of forest persistence across the landscape.

Black spruce (Picea mariana (Mill.) Britton, Sterns & Poggenb.) is one of the most common tree species in the boreal forest. However, there is limited information on one of the major disturbance agents, eastern spruce dwarf mistletoe (Arceuthobium pusillum Peck; EDM) a native, parasitic plant that influences stand development especially at the southwestern range limit of black spruce in Minnesota. The goal of our study was to quantify overstory and understory (sapling and seedling) structure and composition in productive black spruce stands across three EDM severity categories: uninfected (0% EDM), low ( 50% of stand infected with EDM) across northern Minnesota during the summer of 2017. The presence of EDM infection in stands shifted species composition and structure compared to uninfected stands. Uninfected stands were dominated by black spruce in both overstory and understory and on average had a uni-modal diameter distribution. Both low and high EDM severity stands had significantly greater overstory species richness, Shannon’s diversity index, and Shannon’s Evenness compared to uninfected stands. However, stands with high EDM infections had the most black spruce infected with EDM in both the overstory and sapling layer, which will likely kill the infected trees within seventeen years and may result in a shifting in forest composition or a transition to non-forested conditions. The presence and severity of EDM influences stand structure and composition and subsequently stand development. Depending on the goals and objectives and ultimate desired future conditions both at the stand and the broader landscape level, natural resource managers may choose more or less intensive management of EDM.

The black spruce cover type occupies roughly 10% of Minnesota&rsquo, s 7 million hectares of forestland, and is an important species, both ecologically and economically. A clearcut regeneration harvest is the main silvicultural system in black spruce in this region. The effects of managing black spruce with alternative silvicultural methods in the Lake States remains largely understudied. Here, we examine a silviculture study in lowland black spruce to assess the performance of two diameter growth models fit to this data compared to a widely-used model. Six silvicultural treatments (clearcut strips, clearcut patches, thinning, group selection, single-tree selection, and shelterwood) and a control were treated and measured around 1950, with a follow-up measurement occurring 10 years later. Fixed- and mixed-effects growth-models were adapted from the previous work, and fit to 10,231 observations and compared to a recently released diameter growth model. The mixed-effects model using treatment, compartment, and plot as nested random effects outperformed the fixed-effects model, and outperformed a model proposed for use in the Lake States variant of the Forest Vegetation Simulator that was fit to this data. This modeling approach of localized growth models across a wide-range of diameters (9.1&ndash, 32.1 cm) more accurately predicted the diameter growth in lowland black spruce than the conventional approach of using separate models for large (&gt, 12.7 cm) and small (&le, 12.7 cm) diameter trees.

Forest management situations are intrinsically challenging due to the nature of being an interconnected and multi-faceted problem. Integrating ecological, social, and economic objectives is one of the biggest hurdles for forest planners. Often, decisions made with the interest of producing a specific ecosystem service may affect the production of other forest ecosystem services. We present a forest management scheduling model that involves multiple ownerships and addresses the joint production of two ecosystem services: timber and upland hardwood old forest. We use a marginal value approach to evaluate old forest. We analyze the impacts of considering different management options, shapes and levels of marginal value functions for old forest, and potential benefits of rewarding the major forest land ownership groups to produce old forest. Results show the downward-sloping marginal value function as a compromise strategy and the benefits of applying it over approaches using either fixed values or targets for addressing ecosystem services. A decomposition model was useful for recognizing important stand-level detail. A broad landscape and multiple ownership approach helped identify interconnections between forest cover types and between landowner groups.

Contemporary forest planning has tasked managers with developing goals associated with resistance and resilience. In practice, silviculturists use forest structure and tree species composition to characterize goals and desired future conditions, write prescriptions, and monitor outcomes associated with resistance and resilience. Although rarely discussed in the exploding literature relating to forest resistance and resilience, silvicultural regeneration methods are important and underutilized tools to meet these goals. We propose alternative silvicultural systems for building resistance and resilience to two common large-scale bark beetle disturbance agents in the Intermountain West, United States: mountain pine beetle (Dendroctonus ponderosae Hopkins) and spruce beetle (Dendroctonus rufipennis Kirby). Shelterwood, and shelterwood-with-reserves, silvicultural systems provide the desirable facilitative characteristics of a mature overstory on maintaining advance reproduction and the establishment of new cohorts of desirable tree species. These also allow the timely regeneration of large treatment areas necessary to rapidly promote desired future conditions in the face of inevitable disturbance. When implemented proactively, regeneration treatments allow silviculturists to take advantage of currently existing vegetation for the creation of age class and tree species diversity. In general, these examples illustrate the need for proactive planning for regeneration in response to any disturbance where desired future conditions include particular species. Furthermore, we argue that timely silvicultural interventions that focus on regenerating trees may be a key factor in achieving goals relating to resilience to specific disturbance types. Waiting until after the disturbance has occurred could result in the lost opportunity to establish desired species composition or stand structure—and may well result in a considerable restoration challenge.

As forest communities continue to experience interactions between climate change and shifting disturbance regimes, there is an increased need to link ecological understanding to applied management. Limber pine (Pinus flexilis James.), an understudied species of western North America, has been documented to dominate harsh environments and thought to be competitively excluded from mesic environments. An observational study was conducted using the Forest Inventory and Analysis Database (FIAD) to test the competitive exclusion hypothesis across a broad elevational and geographic area within the Intermountain West, USA. We anticipated that competitive exclusion would result in limber pine’s absence from mid-elevation forest communities, creating a bi-modal distribution. Using the FIAD database, limber pine was observed to occur with 22 different overstory species, which represents a surprising number of the woody, overstory species commonly observed in the Intermountain West. There were no biologically significant relationships between measures of annual precipitation, annual temperature, or climatic indices (i.e. Ombrothermic Index) and limber pine dominance. Limber pine was observed to be a consistent component of forest communities across elevation classes. Of the plots that contained limber pine regeneration, nearly half did not have a live or dead limber pine in the overstory. However, limber pine regeneration was greater in plots with higher limber pine basal area and higher average annual precipitation. Our results suggest limber pine is an important habitat generalist, playing more than one functional role in forest communities. Generalists, like limber pine, may be increasingly important, as managers are challenged to build resistance and resilience to future conditions in western forests. Additional research is needed to understand how different silvicultural systems can be used to maintain multi-species forest communities.

Within the Central Rocky Mountains, spruce beetle populations have the potential to rapidly transition from endemic to epidemic levels in the spruce-fir (Engelmann spruce and subalpine fir) forest type. Conventional management has focused on creating resistance to spruce beetle outbreaks by manipulating the overstory density and composition. Three silvicultural treatments, single tree selection, group selection, and shelterwood with reserves, were established in a spruce-fir forest in northern Utah with the goals of increasing both resistance and resilience to outbreaks. Resistance and resilience metrics were explicitly defined. Pre-harvest and two post-harvest measurements were used to assess how the different silvicultural treatments influenced the metrics. The shelterwood with reserves was the only treatment to meet both the resistance and resilience criteria. This treatment, while not traditionally used, created a stand structure and composition that will be most resilient to climate induced increases in spruce beetle caused tree mortality. However, there will be a trade-off in composition and structure, especially Engelmann spruce, after a spruce beetle epidemic because the created structure is more uniform with fewer groups and gaps than commonly observed in spruce-fir forests. With changing climatic conditions, proactive forest management, such as the shelterwood with reserves in the spruce-fir forest type, is the best method for increasing short-term resistance and long-term resilience to spruce beetle outbreaks.