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In 1996 we initiated a study to evaluate several techniques for measuring light under broadleaf canopies. Hourly average photosynthetic photon flux density and percent transmittance were measured 1 m above the ground at four points in each of three canopy densities created by a spacing experiment in a 35-year-old paper birch (Betula papyrifera Marsh.) dominated stand located near Prince George, B.C. At each point, fisheye photographs were taken and LAI-2000 plant canopy analyzer (LAI-2000), spherical densiometer, and competition index (Lorimer'sindex) measurements were made. Percent transmittance measurements onan overcast day (1-h average), transmittance measured over periods of 3 h or longer on a clear day, LAI-2000 diffuse noninterceptance measurements, and gap light index determined from fisheye photographs were strongly correlated with growing season percent transmittance (r2>= 0.96) as was competition index (r2 = 0.928). Concave spherical densiometer measurements and midday percent transmittance measurements on clear days were also well correlated with measured percent transmittance (r2>= 0.89). Estimates of understory light by the LITE model were strongly correlated with growing season percent transmittance. Correlations improved with increasing length of the period simulated (r2 = 0.755 for a point measurement on a clear day; r2 = 0.936 for an entire sunny day;and, r2 = 0.953 for the entire growing season). However, this version of the model underestimated percent transmittance in these spaced birch stands by 34-90%. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As wildfires are increasingly causing negative impacts to communities and their livelihoods, many communities are demanding more proactive and locally driven approaches to address wildfire risk. This marks a shift away from centralized governance models where decision-making is concentrated in government agencies that prioritize reactive wildfire suppression. In British Columbia (BC), Canada, Community Forests—a long-term, area-based tenure granted to Indigenous and/or local communities—are emerging as local leaders facilitating proactive wildfire management. To explore the factors that are enabling local governance approaches to managing wildfire risk, we conducted semi-structured interviews with 26 Community Forest managers across BC. Managers highlighted financial and social capacity, especially trust and relationships with both community members and government agencies, as crucial factors influencing their ability to undertake proactive management. These factors enable Community Forests to address wildfire risk not only within their own tenure area, but also at household, community, and landscape scales, while balancing diverse community values, objectives for forest management, and legal and policy obligations. Despite ongoing challenges, Community Forests emphasized the importance of scaling up their efforts to address wildfire risk and are a critical form of local wildfire governance that can help advance proactive wildfire management across BC. [ABSTRACT FROM AUTHOR]

Forestry is becoming more complex as a result of diverging societal demands. Indigenous Peoples' reconciliation and the challenges of climate change call for research that embraces transdisciplinarity, reciprocity, and problem-focused learning at the landscape scale. Both globally and in Canada, forestry and forest research are struggling to keep pace with this growing complexity. Place-based collaborative research and learning initiatives, described here as "learning landscapes," offer an under-explored approach to meeting diversifying goals for forest landscapes. We describe recent progress in Quesnel, British Columbia, where researchers and local institutions are engaging to strengthen resilience and innovation in the forest sector. We first define the concept of learning landscape in the context of transdisciplinary sustainability science, and then illustrate this approach using the case study of Quesnel. We describe a process of systems diagnosis, including asset mapping and analysis of potential forestry pathways through a "best bets" framework. We propose a Theory of Change as a way forward, outlining opportunities for government, industry, and communities in developing regional capacity for integrated management and high-value forest products. We reflect on the contributions of learning landscapes to knowledge generation, experiential learning, and institutional development, and discuss implications for steering decision-making in locally driven sustainability transitions. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Provides information on the 4th International Workshop on Disturbance Dynamics in Boreal Forest held at the University of Northern British Columbia on August 9 to 12, 2002. Issues involving forest management discussed at the event; Keynote speakers who were present in the workshop; Discussion on the importance and role of disturbance in shaping boreal forest.

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Northern Secwepemc First Nations of central British Columbia are facing serious communication challenges in relation to the comanagement of natural resources in their traditional territories. For First Nations’ managers, communication by speaking and listening and by sharing stories continues to be important for maintaining traditional ecological knowledge and culture. However, in the dominant discourse currently used by management authorities, emphasis is placed on communication products represented in reading and writing, often in electronic format. This dichotomy is leading to communication crises, with traditional ecological knowledge being required to fit within a rigid technology of literacy. The hypothesis that the Northern Secwepemc First Nations are leading transformation initiatives toward sustainable management in their territories and that shared knowledge and responsibility emerges from new growth opportunities in crisis situations has been tested using the case study survey method for inquiry. Results indicate there is potential for transformation towards forest comanagement in Northern Secwepemc territories in times of crises; however, certain conditions such as adequate staffing, funding, and training must first exist at the site level of management for both provincial and Aboriginal managers, to make the best use of emergent opportunities for collaboration. Les Premières nations Northern Secwepemc dans le centre de la Colombie-Britannique font face à de sérieux défis de communication reliés à la cogestion des ressources naturelles dans leurs territoires ancestraux. Pour les gestionnaires des Premières nations, il est encore important de communiquer en parlant, en écoutant et en partageant des légendes pour conserver la culture et les connaissances écologiques traditionnelles. Cependant, dans le discours dominant couramment utilisé par ceux qui régissent l’aménagement, l’emphase est mis sur les produits de communication qui font appel à la lecture et à l’écriture, souvent sous la forme de documents électroniques. Cette dichotomie entraîne des problèmes de communication lorsque les connaissances écologiques traditionnelles doivent s’adapter à une technologie rigide fondée sur la lecture et l’écriture. L’hypothèse voulant que les Premières nations Northern Secwepemc soient en train d’évoluer vers l’aménagement durable dans leurs territoires et que le partage des connaissances et des responsabilités émerge à travers de nouvelles occasions de croissance, engendrées par des situations de crise, a été testée à l’aide de la méthode des cas comme outil d’enquête. Les résultats indiquent qu’une évolution vers la cogestion de la forêt dans les territoires des Northern Secwepemc pourrait survenir en période de crise. Cependant, certaines conditions, telles des effectifs, des fonds et un entraînement adéquats, doivent d’abord être remplies à l’échelon des gestionnaires sur le terrain, tant pour les gestionnaires provinciaux qu’aborigènes, afin de profiter au maximum des occasions de collaboration qui se présentent. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ten-year height data from 232 open-pollinated interior spruce families tested in five seed planning zones located in north-central interior British Columbia were used to investigate the extent and pattern of genotype by environment (G×E) interaction and to examine the validity of the seed planning zone delineation in this region. The G×E interaction in the entire region was both statistically and practically significant, with an estimated type b genetic correlation coefficient of 0.64. The detected geographic pattern of the G×E interaction indicates that the old delineation is overly conservative, and consolidating the five old zones into the two new zones is a valid decision. A procedure was developed to convert the expected genetic gain, with respect to the old zone, to the new zone when seed from a rogued local seed orchard is used for reforestation in the entire new zone. A similar procedure was also proposed to predict the breeding value of an individual that was only tested in the old zone of its origin with respect to the new zone. Given the detected amounts of the G×E interaction, and considering other factors, using three to five sites in each new zone for the second-generation progeny testing seems to be appropriate.L'auteur a étudié, chez l'épinette de l'intérieur, l'ampleur et l'allure de l'interaction génotype × environnement (G×E) ainsi que la validité de la délimitation des zones semencières de la région du centre nord de l'intérieur en Colombie-Britannique, à l'aide des données de hauteur à 10 ans de 232 descendances à pollinisation libre testées dans cinq zones semencières de la région. L'interaction G×E pour la région entière était significative, tant au plan statistique qu'à celui des incidences pratiques, avec un coefficient de corrélation génétique de type b de 0,64. Le patron de variation géographique de l'interaction G×E indique que l'ancienne délimitation est trop conservatrice, et que la fusion des cinq anciennes zones en deux nouvelles représente une solution valide. L'auteur a développé une procédure afin de convertir le gain génétique espéré dans le cadre de l'ancienne zone en fonction de la nouvelle zone, en assumant que les semences du verger à graines local éclairci sont utilisées pour l'ensemble du reboisement dans la nouvelle zone. Également, des procédures similaires ont été proposées pour prédire la valeur en croisement d'un individu en fonction de la nouvelle zone, alors qu'il n'avait été testé que dans son ancienne zone d'origine. Étant donnée l'ampleur observée de l'interaction G×E et en considérant d'autres facteurs, l'emploi de trois à cinq sites par nouvelle zone apparaît approprié pour l'évaluation des descendances de seconde génération.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Soluble organic N (SON) is recognized to be a source of N for plants, but the few studies of the effects of clear-cut harvesting on SON levels have reported inconsistent results. SON and soluble inorganic N (SIN) contents were measured in 1 mol/L KCl extracts of soil from forests and clearcuts in coastal cedar–hemlock forests near Port McNeill, B.C., and in high-elevation spruce–fir forests near Sicamous, B.C. To characterize the seedling root environment, sampling was confined to the top 20 cm of soil (consisting of forest floor at Port McNeill and forest floor plus mineral soil at Sicamous). Amino acid N and microbial N were determined on subsets of the samples. At both sites, SON content tended to be lower in clearcuts than in forests. Lower SON contents in clearcuts were caused by the removal of F-layer forest floor at Port McNeill and by reduced SON concentrations in the forest floor at Sicamous. Correlation analyses indicated close relationships between moisture content, SIN, SON, and microbial N. Changes in SON, SIN, and microbial N concentrations during buried bag incubations could not be explained simply by exchange among these three N pools. Free amino acid N accounted for 1–1.5% of the total SON content.L'azote (N) organique soluble est une source connue de N pour les plantes mais les quelques études qui portent sur les effets de la coupe à blanc sur les niveaux de N organique soluble rapportent des résultats inconsistants. Le contenu en N soluble organique et inorganique a été mesuré dans des extraits de sols au KCl (1 mol/L) provenant de forêts et de coupes à blanc dans des forêts côtières de thuya et de pruche près de Port McNeill et de forêts d'épinette et de sapin situées à haute altitude près de Sicamous, en Colombie-Britannique. Pour caractériser l'environnement du système racinaire des semis, l'échantillonnage a été limité aux premiers 20 cm de sol; ce qui correspond à la couverture morte à Port McNeill et à la couverture morte et au sol minéral à Sicamous. L'azote microbien et sous forme d'acides aminés a été mesuré sur des sous-ensembles des échantillons. Dans les deux stations, le contenu en N organique soluble avait tendance à être plus faible dans les coupes à blanc que dans les forêts. Le plus faible contenu en N organique soluble dans les coupes à blanc était dû à l'enlèvement de l'horizon F dans la couverture morte à Port McNeill et aux faibles concentrations de N organique soluble dans la couverture morte à Sicamous. Les analyses de corrélation indiquent qu'il y a une étroite relation entre le contenu en humidité, N inorganique soluble, N organique soluble et N microbien. Les changements dans la concentration de N organique soluble, de N inorganique soluble et de N microbien lors de tests d'incubation avec des sacs enfouis ne peuvent être expliqués simplement par les échanges entre ces trois pools de N. L'azote sous forme d'acides aminés représentait 1 à 1,5 % du contenu total de N organique soluble.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Headwater streams, varying in flow persistence from ephemeral to intermittent to perennial, provide the tightest coupling between water and land, yet they often receive the least protection during forest management. We described communities of aquatic insects in perennial, intermittent, and ephemeral channels surrounded by old-growth forest and 4- to 8-year-old clearcuts in Clayoquot Sound, British Columbia, to determine whether temporary streams have unique aquatic communities and to examine the short-term impacts of harvesting. We measured flow persistence, stream size, canopy cover, organic detritus, and algal biomass in 19 streams. We sampled aquatic invertebrates with a combination of emergence cages and kicknet samples. Temporary and old-growth streams had more organic detritus and a higher abundance of shredders. Perennial and clearcut streams had a higher abundance of some algal grazers, but not higher algal biomass. Insect richness was similar in intermittent and perennial streams of each seral stage but lower in ephemeral streams. Intermittent streams contained four taxa not found in the other stream classes; perennial and ephemeral streams had none. Communities of aquatic insects differed between streams surrounded by clearcuts and old growth, and varied with continuity of flow. [ABSTRACT FROM AUTHOR]

We have characterized canopy geometry and light transmission by the nine dominant conifer and broad-leaved tree species of the interior cedar-hemlock (ICH) forests of northern British Columbia. Our field data were used to parameterize a spatially explicit model of light transmission through mixed-species forests. That model, a component of the forest dynamics simulator SORTIE, was developed for eastern deciduous forests, and this paper presents a test of that model in a very different ecosystem. Our results show that individual crowns of the ICHforests intercepted much more light than species of eastern deciduous forests but that the canopy as a whole allowed greater light penetration, largely because of openings between the relatively narrow, conical crowns of the western conifers. Light transmission by individualcrowns was correlated with shade tolerance among the conifers (as ineastern deciduous species), but crown depth was not (in contrast with eastern species). Despite the fundamental differences in the natureof light transmission in the two ecosystems, the SORTIE light model developed for eastern deciduous forests was effective at predicting spatial variation in understory light levels in these western coniferous forests. The goodness of fit of such a simple model suggests that the most important factors regulating spatial variation in understorylight levels in these forests are simply the sizes and distribution of nearby trees, and the local sky brightness distribution. Discrete canopy gaps represent a special case in which a region of the canopy is not occupied by crowns. [ABSTRACT FROM AUTHOR]

On 14 April 1994, the British Columbia government announced a new stumpage formula that, at then-expected product prices, increased the average charge by about $12/m3 and more than doubled the rate at which stumpage fees change when lumber prices change. Most of the increased revenues are reinvested in the forest sector by a new organization, Forest Renewal British Columbia (FRBC), created specifically for that purpose. Using standard event-study methodologies, this paper documents the net effect of the fee increases and new policy direction on British Columbia forest products companies. After controlling for firm-specific risk and the decline in the Toronto Stock Exchange that occurred at about the same time, the new stumpage policy extracted about $1.0 billion from shareholders of the firms studied, andperhaps $2.4 billion from all licencees (an amount roughly equal to the capitalized after-tax cost of the higher fees). The impact on individual firms is highly correlated with the allowable annual cut (AAC) in replaceable licenses each holds, with an average impact of about$33.3/m3 of AAC. The market appears to have discounted both the good news about offsets in impending timber-supply reductions that the creation of FRBC implies and the reductions in earnings riskthat the new stumpage system provides. When added to the increased regulatory costs associated with the new provincial Forest Practice Code, the timber-fee increases appear to have fully depleted the value of holding British Columbia timber quotas. [ABSTRACT FROM AUTHOR]