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Culturally modified trees (CMTs) provide tangible evidence of long-term forest use by Indigenous peoples. In Northwest Coast cedar forests, this record rarely spans beyond the last three centuries because older bark-harvest scars have been obscured through taphonomic processes such as natural healing and decay. Thus, archaeological visibility and identification are hindered. Here, I recover chronologies of ancient forest harvesting using a post-impact assessment methodology of targeting old-growth clear-cuts in southern Nuu-chah-nulth territories on the west coast of Vancouver Island, British Columbia, Canada. Bark-peeling scars are identified and dated in cross section by growth-ring patterns of recently logged trees. Approximately half of all bark-peeling scars are “embedded" inside healing lobes, suggesting at least half of all such CMTs are effectively invisible in standing forests. Features in these post-impact surveys predated those discovered in conventional archaeological impact assessments by a mean of almost a century. Additionally, one of the oldest continually used cultural forests ever recorded, dating to AD 908, is found in the Toquaht Nation traditional territory. These findings uncover measurable frequencies of cedar-bark harvesting generations prior to the contact period and reveal the inadequacy of heritage protections for old-growth cedar stands. [ABSTRACT FROM AUTHOR]

* Premise of the study: Geographically peripheral (marginal) populations are expected to have lower genetic diversity and higher genetic differentiation than geographically core (central) populations as a result of supposedly lower effective population size (No) and higher genetic drift, founder effect, fragmentation, and isolation in peripheral than in core populations. Here we ad- dress this issue for a long-lived plant species, eastern white cedar (Thuja occidenmlis). * Methods: Genetic diversity and population structure of 13 natural populations of eastern white cedar from its Canadian eastern peripheral and core natural ranges in New Brunswick, Nova Scotia, and Prince Edward Island were studied using six nuclear microsatellite DNA markers. * Key results: The core populations of eastern white cedar had significantly higher allelic diversity (mean A = 8.83, Ar = 8.13, Ae = 4.03) and Ne (428) than the peripheral populations (A = 6.64, Ar 6.15, Ae = 3.12, Ne = 198). However, expected heterozygosity was similar in the core (He = 0.64) and peripheral (He = 0.60) populations. Genetic differentiation was significantly higher among the peripheral (FST = 0.089) than among the core (FST 0.032) populations. No genetic differentiation (FST/Φ RT = 0.000) was detected between core and peripheral regions. * Conclusions: Peripheral populations have significantly lower N~ and genetic diversity in terms of allelic diversity (richness) and significantly higher genetic differentiation than the core populations of eastern white cedar in its Canadian eastern range. However, core and peripheral populations have similar levels of expected heterozygosity. Implications for conservation of eastern white cedar genetic resources are discussed. [ABSTRACT FROM AUTHOR]

Introduction and Aims. The Cedar Project is a community-based study aiming to identify variables associated with ever being on methadone maintenance treatment (MMT) among young Aboriginal people using drugs and to discuss possible barriers to MMT in this population. Design and Methods. This is a prospective cohort study with recruitment by health-care providers, outreach, and word of mouth in Vancouver and Prince George. Participants included 605 Aboriginal participants who were age 14-30 years, reported illicit drug use in the month prior to enrolment, and provided written informed consent. Variables associated with ever being on MMT were analysed through χ2-testing and multivariate logistic regression, limited to people reporting opioid use (n = 397). Results. Less than half of participants reporting daily injection of opioids had ever been on MMT. In adjusted multivariate logistic regression analyses, older age [odds ratio (OR) 1.17; 95% confidence interval (CI) 1.08-1.28)]; female gender (OR 3.76; 95% CI 2.00-7.07); hepatitis C antibody positivity (OR 2.76; 95% CI 1.53-4.95); and daily opioid injection (OR 2.59; 95% CI 1.46-4.61) were positively associated with ever being on MMT. Weekly or more alcohol use (OR 0.43; 95% CI 0.21-0.87) was negatively associated with ever being on MMT. Discussion and Conclusion. MMT access by young Aboriginal people is low. The associations between MMT use and other variables need further study to steer efforts directed at recruitment into MMT. The removal of barriers to MMT and inclusion of young Aboriginal people in the development of treatment programs based on Indigenous values are urgently required to help Aboriginal people who use drugs.[Yang J, Oviedo-Joekes E, Christian KWM, Li K, Louie M, Schechter M, Spittal P. The Cedar Project: Methadone maintenance treatment among young Aboriginal people who use opioids in two Canadian cities. Drug Alcohol Rev 2011;30:645-651] [ABSTRACT FROM AUTHOR]

Orographic precipitation over interior mountains has resulted in the formation of the inland temperate rainforest, where certain stands are potentially antique and support a rich flora of epiphytic macrolichens. We documented macrolichen diversity across three age-classes in forests of the Interior Cedar–Hemlock biogeoclimatic zone (i.e., ICHwk3 subzone) east of Prince George, British Columbia. Our objectives were to report changes in lichen communities with stand age, identify potential indicators of antiquity, and investigate the functional role of dominant species in the ecosystem. We identified 41 taxa, including 4 alectorioid lichens, 21 foliose chlorolichens, and 16 old-growth-associated chlorolichens and cyanolichens. Older forests supported more species than young or mature forests. The abundance of Lobaria pulmonaria (L.) Hoffm. was strongly correlated with this increase in diversity and may therefore be an appropriate indicator of stand age in the ICH. The increase in L. pulmonaria and other N2-fixing cyanolichens with stand age may have significant implications for forest nitrogen budgets in the interior of British Columbia, where atmospheric nitrogen deposition is relatively low and biological N2 fixation accounts for nearly all of the nitrogen lost to forest harvesting. We hope that this greater understanding of lichen ecology across age-classes will promote sustainable stewardship of the remaining old-growth forests of inland British Columbia. [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]

As the climate begins to warm optimal conditions for various tree species will undergo geographical shifts. Over the long-term, the ranges of particular species will respond through slow migrations to the new optimal climatic zones. In the short-term, trees currently or soon to be rooted will be forced to endure the altered climatic regimes in their current positions. The features of the future climate that will drive or limit their radial growth rates will, in some cases, cause deviations from past environments. Some species will lose their competitive advantage while others may gain the ability to become dominant. This ongoing project is in the process of forecasting radial growth response to future climates using past tree growth data, past weather data and projected coupled global climate model data. The radial growth models being produced will provide a means to identify the most at risk species and the most potentially robust tree types. Outcomes will help determine new sustainability goals in both conservation and resource use areas. Results of the projected species forecasts indicate that white pine will not be greatly affected by increases in temperature. Eastern hemlock should increase its growth rate by up to 60% by the year 2100 as the growing season lengthens. Eastern white cedar reacts poorly to hotter drier July conditions and it should decrease its growth rate by as much as 75% by the year 2100. Meanwhile red and black spruces appear to hold remain stable or increase their growth rates slightly. What is not known exactly is if the potential for an increase in insect activity will limit their success. [ABSTRACT FROM AUTHOR]