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The relationship between forest stand composition in southern interior British Columbia and fluorescent pseudomonad bacteria populations was investigated using seedling bioassays. The objectives of this study were to (i) compare the relative population sizes of fluorescent pseudomonads baited from soils in pure paper birch (Betula papyrifera Marsh.), pure Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and mixed stands of the two species and (ii) determine if fluorescent pseudomonads from these soils have inhibitory effects against the root pathogen Armillaria ostoyae (Romagn.) Herink in vitro. Soil from birch stands supported four times more pseudomonads on seedling baits than soil from Douglas-fir stands, with the mixed stands intermediate. Soil from young stands yielded twice as many rhizosphere pseudomonads as soil from mature stands. Pseudomonad population size was positively correlated with percent cover and density of birch, and negatively correlated with basal area of Douglas-fir, percent cover of Douglas-fir, and carbon/nitrogen ratio of the soil. Greater than 50% of the fluorescent isolates reduced radial growth of A. ostoyae by more than 20% and greater than 90% reduced biomass of the fungus in dual culture tests. Cell-free bacterial culture filtrates added to the growth medium also reduced growth of A. ostoyae. This study provides evidence that paper birch provides a more favorable environment for fluorescent pseudomonads than Douglas-fir and suggests a mechanism by which paper birch can positively influence the susceptibility of managed forest stands to Armillaria root disease. [ABSTRACT FROM AUTHOR]

There is an increasing interest in mixed conifer-broadleaf stands as a way to increase the diversity and productivity of managed forests. This study examined the impacts of varying densities of planted broadleaf trees on conifer performance, total stand productivity, and understory plant cover 20 years after stand establishment. The study took place in the Malcolm Knapp Research Forest in Maple Ridge, British Columbia. It used a randomized complete block design to compare treatments containing low, moderate, or high broadleaf densities added to a constant conifer density. Each block contained a conifer-only plot as a control. Conifers were composed of equal amounts of western hemlock, western redcedar, and Douglas-fir. Broadleaves were composed of either red alder or paper birch. We found that conifer volume was significantly lower in most broadleaf treatments relative to the control, due to lower hemlock and redcedar volumes. Douglas-fir, on the other hand, had a higher volume—albeit not significant—in the broadleaf treatments. There were no significant differences in total stand volume between any of the treatments and the control. Shrub cover was significantly higher in the low and high alder treatments relative to the control, but there were no differences in shrub cover between birch treatments and the control. The results suggest that low alder density provides a good balance of conifer yield and understory development. [ABSTRACT FROM AUTHOR]

Old growth is disappearing globally, with implications for biodiversity, forest resilience, and carbon storage; yet uncertainty remains about how much exists, partly because assessments stratify ecosystems differently, sometimes obscuring relevant patterns. This paper compares portrayals of British Columbia's (BC) old-growth forest stratified in two ways: by biogeoclimatic variant, as per policy, and by relative site productivity. Our analyses confirm provincial government claims that about a quarter of BC's forests are old growth but find that most of this area has low realized productivity, including subalpine and bog forests, and that less than 1% is highly productive old growth, growing large trees. Within biogeoclimatic variant, nearly half of high-productivity forest landscapes have less than 1% of the expected area of old forest. Low-productivity ecosystems are over-represented in protected forest. We suggest that the experiment of managing old growth solely by biogeoclimatic variant has failed and that current forest policy, in combination with timber harvesting priorities, does not maintain representative ecosystems, counter to the intent of both policy and international conventions. Stratifying old growth by relative productivity within biogeoclimatic variant seems an appropriate method to portray ecosystem representation, potentially increasing the probability of maintaining ecosystem resilience. [ABSTRACT FROM AUTHOR]

Collaborative natural resource governance is increasingly relied upon to resolve conflicts, generate social and ecological benefits, and increase implementation of decisions. Trust is widely recognized as critical to successful collaborative natural resource governance; however, the multidimensional nature of trust has been underexplored in this context, and few studies specifically address collaborations involving Indigenous Peoples. Literature on collaborative governance involving Indigenous Peoples emphasizes issues of power-sharing, participation, and intercultural purpose and insights into how trust created with these considerations in mind have the potential to improve processes and outcomes. This paper used a case study of collaborative forest governance on Haida Gwaii, an archipelago located off the coast of British Columbia, Canada, to identify linkages between power-sharing and individual, interpersonal, and institutional influences on trust. Collaborative forest resource governance on Haida Gwaii formally began following signing of the Strategic Land Use Agreement (2007) and the Kunst'aa guu-Kunst'aayah Reconciliation Protocol (2009) and had led the Haida to achieve several of their goals for resource management. The research linked theoretical and empirical literature on collaborative governance and trust with empirical evidence gathered from 19 semi-structured interviews with current and former members of the Haida Gwaii Management Council and the Solutions Table and identified five individual influences, five interpersonal influences, and four institutional influences on trust. [ABSTRACT FROM AUTHOR]

When the Government of British Columbia (BC) introduced the Community Forest Agreement Program in 1998, it permitted a range of governance structures to allow flexibility and to learn which structures might be most appropriate for this new form of forest tenure. One structure that became fairly common was collaboration between Indigenous and non-Indigenous communities. This paper characterizes and analyzes the advantages of this collaborative governance model in three ways, identifying (1) what benefits this model entails, (2) how these are illustrated in three different community forests, and (3) how these forms of collaboration fit into a co-management spectrum. Because some of these benefits involve communities having greater degrees of power in forest governance, the model invites a consideration of the types of decision-making power experienced by Indigenous communities partnering or collaborating in BC community forests, as well as the types and range of benefits for all parties emerging from these collaborations. Fourteen indicators of the benefits of collaboration are identified, building on the discovery of five new benefits heretofore unrecognized in the literature. These understandings permit a more nuanced assessment of this particular type of co-management, leading to the generation of three new, broader hypotheses regarding the conditions that support co-management. [ABSTRACT FROM AUTHOR]

This paper investigates the practices of the value-added wood products industry in British Columbia (BC) with respect to innovativeness using the results of an online survey. The survey employed an indirect self-evaluation scale to assess the propensity to create and (or) adopt new products, processes, and business systems. Using chain of custody certification as an example of business systems innovation, this study also investigated the attitudes of the value-added wood products manufacturers, who were already certified or who may become certified, towards innovation in this form. Results show that the respondents rated themselves as more innovative with respect to business systems innovation compared with product and process innovations. Overall, innovation levels were low in the BC value-added wood products sector, a result which was confirmed in the case of chain of custody certification. [ABSTRACT FROM AUTHOR]

Vegetation-management practices are applied in temperate-zone forests on the assumption that changing the competitive environment between conifers and unwanted vegetation will improve conifer productivity. We review this assumption using research examining interactions between paper birch (Betula papyrifera Marsh.) and conifers in the highly productive Interior Cedar Hemlock zone of British Columbia. We have found that both competition and facilitation are important in young plantations, where paper birch competes for light, reducing growth of shade-intolerant conifers, but having a facilitative effect on shade-tolerant conifers. This facilitative effect may result from greater ectomycorrhizal diversity, population sizes of Armillaria ostoyae (Romagn.) Herink antagonistic bacteria, and associative nitrogen fixation in plantations where interior Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) is mixed with paper birch. Where paper birch is manually cut or girdled, conifers grow faster in diameter, but more die as a result of A. ostoyae root disease, and these responses increase with increasing weeding intensity. The weeding treatments do not affect plant community species richness but reduce paper birch dominants and increase understory structural diversity. British Columbia forest policy has been slow to respond to these findings, and we suggest that as a result, the forested landscape incurs substantial risk. We propose additional pathways for managing Interior Cedar Hemlock mixtures to ensure that the natural mix of forest types in the landscape is maintained. [ABSTRACT FROM AUTHOR]

The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera, Curculionidae), a native insect of North America, periodically reaches population sizes that cause serious economic impact to the forest industry in western North America. The most recent outbreak in British Columbia (BC), Canada, which began in the late 1990s, is only now (2015) abating, after causing unprecedented tree mortality in lodgepole pine ( Pinus contorta Douglas ex. Loudon) forests. In this paper, we make use of permanent research plots to report on the condition of lodgepole pine forests in the Chilcotin Plateau of central BC, which underwent two fully documented mountain pine beetle outbreaks. In this region, the first outbreak started in the late 1970s and lasted until the mid-1980s; the second outbreak began in the early 2000s and ended in 2010. We measured the impacts of these outbreaks in terms of tree mortality and describe the characteristics of the legacies that remain following these outbreaks, including survivors in various canopy layers and levels of existing and new regeneration. We provide evidence in support of the existence of postdisturbance legacies that classify into five distinct stand structure types. Abundant regeneration and surviving intermediate canopy layers in most stands indicate that management actions to restock pine stands in this area will not likely be necessary. The information provided by this study is important for estimating future forest development and timber supply and for forest planning and management. [ABSTRACT FROM AUTHOR]

Commercial forestry has played an important role in the Canadian economy. Yet, First Nations (FNs) communities have not shared equitably in the benefits. Since 2002, the government of British Columbia (BC) has actively sought to address this inequity by increasing the volume of forest harvesting tenures to FNs. The rationale is that rights to harvest will also enhance economic and then social outcomes, as well as address broader legal and political disputes. However, whether these rights can translate into the expected benefits has received little attention. This paper seeks to help address this knowledge gap by interviewing FNs experts and forestry professionals in BC to understand the long-term goals of FNs in forestry, to strategically evaluate how (and if) opportunities from forestry arise, and to identify institutional factors that influence successful participation in forestry. What we found is that forest tenure can promote economic outcomes, but it often comes at the expense of other intrinsic forest values. We conclude that a rights-based approach alone will not achieve the diverse outcomes related to forestry without effective governance by FNs to evaluate and capitalize on the opportunity in ways that are legitimate to the individual community's values. [ABSTRACT FROM AUTHOR]

Wildfire risk assessment research has made considerable progress towards estimating the probability of wildfires but comparatively little progress towards estimating the expected consequences of potential fires. One challenge with estimating wildfire consequences has been to identify a common metric that can be applied to consequences measured in different units. In this paper, we use the preferences of representatives of local fire management agencies as the common consequences metric and apply it to a case study in the southern Gulf Islands, British Columbia, Canada. The method uses an expert survey and a maximum-difference conjoint analysis to establish the relative importance of specific fire consequences. A fire with a major potential for loss of life was considered to be about three times worse than major damage to houses and 4.5 times worse than loss of a rare species. Risk ratings were very sensitive to changes in fire consequences ratings. As the complexity of values at risk and number of stakeholders increase, the most efficient allocation of wildfire prevention, protection, and suppression resources becomes increasingly challenging to determine. Thus, as the complexity of stakeholder representation and values at risk increases, we need to pay increasing attention to quantitative methods for measuring wildfire consequences. La recherche qui porte sur l'évaluation des risques de feu de forêt a fait des progrès considérables concernant l'estimation de la probabilité des feux de forêt mais comparativement peu de progrès concernant l'estimation des conséquences anticipées de feux potentiels. Un des défis de l'estimation des conséquences des feux de forêt consiste à identifier une mesure commune applicable aux conséquences mesurées avec différentes unités. Dans cet article, nous utilisons les préférences de représentants des organismes locaux de gestion du feu comme mesure commune des conséquences et nous l'appliquons à une étude de cas dans le secteur sud des îles Gulf en Colombie-Britannique, au Canada. La méthode utilise un sondage auprès des experts et une analyse conjointe pour établir l'importance relative des conséquences du feu. Un feu qui a de fortes possibilités de causer des pertes de vie a été considéré environ trois fois pire que des dommages importants aux habitations et 4,5 fois pire que la perte d'une espèce rare. L'estimation des risques était très sensible aux changements dans le classement des conséquences du feu. À mesure que la complexité des valeurs menacées et le nombre d'intervenants augmentent, il devient de plus en plus difficile de déterminer comment allouer le plus efficacement les ressources à la prévention, à la protection et à la suppression des feux de forêt. Par conséquent, à mesure que la complexité de la représentation des intervenants et des valeurs menacées augmente, il faut accorder une attention de plus en plus grande aux méthodes quantitatives pour mesurer les conséquences des feux de forêt. [ABSTRACT FROM AUTHOR]

Abstract: Sustained growth responses and large reductions in rotation length can be achieved by repeatedly fertilizing young boreal forests. This paper reports the effects of different regimes and frequencies of fertilization on the foliar nutrition and growth of 10-year-old sub-boreal white spruce {Picea glauca (Moench) Voss) in central British Columbia. Mean stand volume in treatment plots fertilized twice (at 6-year intervals) with N and B (totaling 400 kg N/ha and 3 kg B/ha) was 20 m3/ha (75%) greater than in the unfertilized control at year 12. Significantly larger stand volume gains (34 m3/ha, 128%) were obtained when S (totaling 100 kg S/ha) was added to this treatment. The inclusion of other nutrients (P, K, and Mg) with N, S, and B did not result in further incremental growth gains. When combined with other nutrients, yearly applications of 100-200 kg N/ha (totaling 1600 kg N/ha) produced 74 m3/ha (277%) more volume compared with the unfertilized stand at year 12. The large effects of fertilization on stand growth were accompanied by large increases in leaf area. Results indicate that repeated fertilization of young sub-boreal spruce forests may offer an excellent opportunity to increase fibre yield and reduce rotation length. [ABSTRACT FROM AUTHOR]

Vertical and horizontal patterns of light within gaps and expansion of trees into gaps were examined in young stands dominated by trembling aspen (Populus tremuloides Michx.) in northeastern British Columbia and northwestern Alberta. Lateral growth of branches of aspen edge trees averaged 15.2 cm/year and was similar to crown expansion rates reported for edge trees in eastern North America. Branches growing into gaps were significantly longer than those growing away from gaps and are likely to lead to gap shrinkage and reductions in light within gaps. However, height growth of edge trees was not significantly different from that of trees within the surrounding stands. Models describing relationships between diffuse transmittance and locations within gaps and surrounding stand height were developed in this paper. Sky view angle (SVA) was found to be effective for predicting transmittance to different locations within gaps. When SVA values exceed 1.2 (at the B.C. sites), white spruce (Picea glauca (Moench) Voss) will receive <40% of full sunlight, which is less than optimal for spruce height growth. [ABSTRACT FROM AUTHOR]

This paper describes the development and implementation of Cambium, an agent-based forest sector model for strategic analysis. This model is designed as a decision-support tool for assessing the effects that changes in product demand and resource inventories can have on the structure and economic viability of the forest sector. Cambium models aggregate product supply as an emergent property of individual companies’ production decisions and stand-level ecological processes. Modeling the forest-products sector as a group of interacting autonomous economic agents makes it possible to include production capacity dynamics and the potential for mill insolvencies as factors in analyzing the effects of market and forest inventory based disturbances. The utility of this model is tested by assessing the impacts of a market downturn in the US forest products market on forest industry structure and mountain pine beetle (Dendroctonus ponderosae Hopkins) salvage harvesting in British Columbia, Canada. Simulation results indicate a significant medium-term timber supply shortage; reduced stumpage revenues; intensive cost competition among primary wood-products manufacturers; and a large number of insolvencies in the panel, lumber, and pulp sectors. [ABSTRACT FROM AUTHOR]

Harvest scheduling decisions are made in an uncertain environment, and current modeling techniques that consider uncertainty impose severe difficulties when solving real problems. In this paper we describe a robust optimization methodology that explicitly considers randomness in most of the model coefficients while keeping the model computationally tractable. We apply the method to schedule harvest decisions when both timber yield and demand of two products are uncertain. Since uncertain coefficients must be independent, uniform, and symmetrically distributed, we only address uncertainty attributable to estimate errors of forecast models. The methodology was applied to a 245 090 ha forest in British Columbia, Canada. We compared the change in harvest decisions and objective function when robust solutions are implemented relative to deterministic solutions. Although probability bounds can be used to a priori define the probability of constraint violations, they produce conservative solutions. We therefore tested the rates of constraint violations by simulation. While traditional deterministic decisions were always infeasible when uncertain data were simulated, robust decisions were much less sensitive to uncertainty and were, to a large extent, protected against the occurrence of infeasibilities. In exchange, reasonable reductions in the objective function were observed. [ABSTRACT FROM AUTHOR]

It is critical to understand how the public prioritizes multiple forestry values when establishing objectives for sustainable forest management. While this is a complex and difficult task, a necessary step is to elicit a broad range of public opinions in forest planning to ensure that decisions serve the needs of various forest stakeholders and society at large. This study seeks to understand how six forest dependent communities in British Columbia prioritize a number of attributes associated with sustainable forest management by using a simple survey-based measurement tool, the Thurstone scale. The results suggest that ecological attributes are a higher priority for survey respondents followed by quality of life, global warming, and economic considerations. This paper explores some of the ramifications of the priorities for sustainable forest management measured in these six communities as well as implications for using the Thurstone scale in processes like Public Advisory Groups. [ABSTRACT FROM AUTHOR]

In this paper, we extend traditional methods of spatial statistics to study spatiotemporal correlations between two different point processes. After introducing the methodology, we apply this analysis to a particular case study of interest in ecology, the interaction between damage by a particular forest pest (western spruce budworm (Choristoneura occidentalis)) and forest fires. Our analysis, which covers parts of British Columbia in the 26-year period from 1970 to 1995, indicates that areas affected by budworm infestation have a significantly decreased risk of forest fire for the 7 years following the infestation. Conversely, forest fires decrease the risk of infestation for at least 6 years after the fire. These temporal correlations extend over a spatial range of at least 25 km. Our study rejects the common assumption that insect infestation necessarily results in increased fire risk. This case study illustrates the utility of point process modeling and spatial statistics to understanding ecosystem dynamics extending over both space and time. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the impact of various socioeconomic conditions on the value of timber tenures in the province of British Columbia. Two timber tenure models were created, one for short-term timber sale licenses and the other for longer term forest licenses. The short-term model revealed that timber sales that were awarded according to a combination of employment, revenue, and manufacturing criteria yielded $8.63/m3 less revenue than timber sales awarded based on revenue alone. Similarly, the long-term model indicates that manufacturing and employment conditions significantly reduce the bid on forest licenses. In both instances, we suggest that such conditions distort the use of timber, labour, and capital. Therefore, we conclude that recent forest policy changes in the province that removed several of these conditions greatly improved economic efficiency. Nevertheless, distribution impacts are likely to be important because resource rents have potentially been redistributed away from rural communities to the provincial government. [ABSTRACT FROM AUTHOR]

This paper examines structural changes and the dynamics of price relationships in the United States (US), British Columbia, Quebec, and Ontario lumber markets. With monthly price series from 1981 to 2002, I used Perron's method to identify structural shifts and the Johansen cointegration analysis and vector-error correction model to determine both short- and long-run price relationships. I found that because of restrictions on federal timber harvests in the Pacific Northwest, price instability experienced in 1992 has caused structural shifts for the US and Canadian lumber prices. I also found that the North American lumber market is indeed integrated, with the US price significantly affecting Canadian prices in both the short and long run. This further indicates that the US market plays a dominant role in price setting in the North American lumber market, as Canadian prices respond to the US price change, but the reverse situation does not occur. [ABSTRACT FROM AUTHOR]

Broadleaf trees are routinely removed from conifer plantations during vegetation management treatments, but whether the removal increases tree productivity or affects root disease and plant diversity is unknown. The effects of manual and chemical reduction of paper birch (Betula papyrifera Marsh.) and trembling aspen (Populus tremuloides Michx.) on conifer survival, growth, root disease incidence, and plant community diversity were investigated for 5 years in Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) and lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) plantations in southern interior British Columbia. Broadleaves were reduced by manual, girdling, and cut-stump glyphosate treatments for 5 years but most severely following cut-stump glyphosate and with a delay due to slow death following girdling. Conifer survival was reduced for 3–5 years following manual cutting or girdling of birch because of a 1.5- to 4-fold increase in mortality due to Armillaria ostoyae (Romagn.) Herink, but this did not occur following cut-stump glyphosate treatment of birch or manual cutting of aspen. Conifer diameter increased with treatment intensity and productivity of the vegetation complex. Competition thresholds were identified for diameter but not survival, although Armillaria-caused mortality tended to increase near the minimum growth threshold. Structural diversity increased following manual cutting and cut-stump glyphosate because birch dominants were removed and understory layers increased, but species richness and diversity were unaffected. Forest managers can expect increased conifer growth with birch removal but also small increases in mortality due to Armillaria ostoyae root disease following manual treatments and loss of large birch trees in all treatments. [ABSTRACT FROM AUTHOR]

Treatments that reduce neighbour density are widely applied in the belief they will improve conifer growth in mixed forests. However, our understanding of stand composition and age effects on competition is poor. We used neighbourhood analysis for 748 target conifer trees to examine interspecific competition within 11-, 25-, and 50-year-old mixed, even-aged stands of paper birch (Betula papyrifera Marsh.), Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco), western redcedar (Thuja plicata Donn ex D. Don), and western larch (Larix occidentalis Nutt.) in southern interior British Columbia. Critical neighbourhood height and distance were identified where competition accounted for the greatest variation in target conifer diameter. Competition processes were emperically examined using relative height indices. We found that critical neighbourhood distance increased with stand age and was greater for larch than for cedar. Critical neighbourhood height was higher for cedar than for Douglas-fir or larch in the 11-year-old stands but lower in the older stands. The most important competitors in the 11-year-old stands were tall neighbours, whereas those in the older stands were short neighbours. We found asymmetrical relationships between target conifers and neighbours for all species and age-classes, indicating a resource preemption mode of competition. To be useful in developing prescriptions for competition management in mixed species stands, competition indices should consider neighbour identity and critical height for each target species. Assessment radius must also be sufficiently large to adequately characterize competition. [ABSTRACT FROM AUTHOR]

This paper examines suspended sediment concentration and stream discharge during freshet in three small sub-boreal forest streams (<1.5 m in width) in the central interior of British Columbia for 1 year prior to (1996) and for 5 years following forest harvesting (1997-2001). Harvesting prescriptions in a 20-m strip beside one stream required complete removal of merchantable timber (>15 cm diameter at breast height (DBH) for pine and >20 cm for spruce), while all stems <30 cm DBH were retained beside a second stream. A third stream remained unharvested as a control. The two riparian treatments were prescribed to test the efficacy of current British Columbia legislation that allows for varying amounts of riparian retention as best management practices for the management of windthrow. Both treated watersheds were clear-cut harvested (approximately 55% removal) in January 1997, and in the following year, temporary access roads were deactivated, including two stream crossings in the low-retention watershed. An increase in peak snowmelt and total freshet discharge was first noted in the second spring following harvest in both treatments and remained above predicted in all subsequent years. Suspended sediment also increased during freshet following harvest but returned to levels at or below preharvest predictions within 3 years or less in the high-retention watershed. [ABSTRACT FROM AUTHOR]