71 resources found

This report details a commercial thinning study conducted in white spruce stands near Calling Lake, Alberta, in 2002, with the aim to understand its impact on forest growth, yield, and overall development. The study investigated three different removal levels (30%, 50%, and 70% of basal area), along with an uncut control. Key aspects examined were the productivity and cost-effectiveness of harvesting and forwarding operations using a Timberjack harvester and forwarder, the extent of damage to residual trees, and the influence of non-merchantable brush on harvester efficiency. The findings indicate that higher removal levels generally led to increased productivity for both machines, and that pre-harvest brushing significantly improved harvester efficiency by enhancing visibility and reducing wasted cuts.

This document delves into the critical aspects of aspen silviculture, addressing the increasing complexity of managing aspen forests due to greater utilization and evolving approaches to mixedwood management. The authors review the mechanisms of aspen regeneration, both through root suckering and seeds, and offer preliminary guidelines for managing the density of aspen stands in their early development. The paper aims to synthesize existing knowledge and identify knowledge gaps to better inform management decisions aimed at achieving various forest composition objectives.

This document investigates how the initial planting density, or espacement, affects the growth of a 27-year-old Sitka spruce plantation in British Columbia. The study examines various stand characteristics, including tree height, diameter, volume, and crown development across different planting densities ranging from 478 to 2990 stems per hectare. The core purpose is to provide foresters with data on optimizing stocking levels for Sitka spruce to enhance timber production and manage stand characteristics more effectively, suggesting a recommended range of 800 to 1400 stems per hectare for saw timber objectives. The findings highlight a trade-off: wider espacements produce larger individual trees and branches, while closer espacements yield a greater total volume per hectare when considering all trees in the stand.

This presentation focuses on the establishment and growth of aspen stands within the Sub-Boreal Spruce zone of British Columbia. It draws upon existing research to discuss key factors influencing aspen regeneration, including the importance of removing apical dominance through disturbances like logging or fire to promote suckering. The presentation also details harvest considerations, such as the benefits of winter harvesting and the negative impacts of excessive canopy retention and soil compaction. The presentation explores the effects of various silvicultural practices and the interactions between aspen and coniferous species like spruce and pine, providing guidance on site selection and stockingregeneration surveys for successful aspen management.

This study focuses on aspen, a vital broadleaf tree, examining its distribution and health in north-central BC and the various threats it faces, including climate change, forest management practices, and ungulate grazing. It explores the ecological implications of potential aspen declines, specifically considering the relationship between aspen and beaver-created shallow water wetlands, offering recommendations for future research and management.

This extension note investigates two site preparation techniques, Rough and Loose mounding and furrowing with a RipPlow, for improving plant re-establishment on forested sites that have been wood mulched during winter industrial activities. The study evaluated the effectiveness of these methods in displacing the mulch and exposing soil to create favorable conditions for revegetation. While both techniques enhanced surface soil heterogeneity and facilitated the regeneration of deciduous species, Rough and Loose mounding proved more consistently effective at moving the mulch. Despite this, the more cost-effective RipPlow method showed promise, particularly in areas with thinner mulch layers, suggesting that supplemental planting might be beneficial in heavily mulched areas treated with this approach.

This technical report explores the viability of commercial thinning as a forest management strategy within the Arrow and Cranbrook Timber Supply Areas of British Columbia. The primary goal was to investigate if commercial thinning could help offset projected wood supply reductions resulting from new forest policies and land-use plans. The study involved a multi-stage methodology: identifying potential forest stands using Geographic Information Systems theming, conducting field inventories and reconnaissance surveys to assess suitability, and modeling the impact of thinning on wood flow. While the project successfully identified potential thinning volumes, it also highlighted significant challenges such as limited road access, unsuitable stand structures, and the need to balance timber extraction with other resource management objectives.

This technical report investigates the impact of silviculture practices on greenup delay in the Nelson Forest Region, specifically within the Cranbrook and Revelstoke Timber Supply Areas. Greenup delay refers to the time it takes for a newly harvested forest stand to reach a specified average height, signaling successful regeneration. The report evaluates how enhanced silviculture techniques, such as site preparation, planting, brushing, and the use of genetically improved stock, can reduce this delay and increase the short-term and long-term timber supply to optimize tree growth and forest yield.

This technical report presents a retrospective investigation of partial cuts within the Golden Forest District. The primary purpose of the study was to explore the relationship between regeneration density and various site factors following partial harvesting. Researchers found that while abundant natural regeneration occurred, its success was not strongly correlated with specific harvest treatments, but rather more significantly influenced by factors like brush potential and site preparation. The report recommends guidelines for residual basal area levels to optimize seed supply and moisture protection in these forest ecosystems.

This handbook outlines the principles and best practices for silvicultural systems in British Columbia, emphasizing a shift toward complex, multi-value forest management in the 21st century. Its primary purpose is to serve as a central reference and conceptual framework for forest professionals to design and implement silvicultural plans that move a stand from its current state to a desired future condition through planned interventions, known as stand development pathways. A crucial and recurring theme is the growing role of First Nations, including their traditional knowledge, values, and stewardship goals, which are integrated alongside ecological, social, and economic objectives. The document provides detailed guidance on technical aspects, such as managing for biodiversity, mitigating risks like windthrow and pests, and utilizing adaptive management for continuous improvement in forestry practices.

This paper investigates how wildfires influence the upward migration of tree species in California's subalpine forests, a phenomenon often linked to climate change. Researchers examined post-fire tree regeneration across various fire severities, focusing on the contrasting responses of shade-tolerant and shade-intolerant conifer species. While overall montane species regeneration decreased in burned areas, shade-intolerant Jeffrey pine showed increased success in severely burned plots, aligning with predictions of higher climatic suitability. Conversely, shade-tolerant red fir regeneration declined significantly with higher fire severity, suggesting that the specific regeneration niche of a species, its ideal post-fire conditions, is critical in determining whether fire facilitates or hinders its range expansion.

This document presents results from a long-term experiment examining the impact of spacing and thinning on coastal Douglas-fir plantations. The study, conducted over 28 years near Lake Cowichan, British Columbia, aimed to understand how different tree densities and thinning strategies affect various growth parameters like diameter, height, basal area, and total and merchantable volume. While acknowledging limitations due to site variation and a lack of replication, the report provides initial insights into managing Douglas-fir stands, emphasizing that higher density generally leads to smaller individual tree growth but greater overall stand volume, whereas thinning, especially heavy or early thinning, can positively influence tree size and merchantable volume.

This document details a long-term forestry study on the growth and yield of 56-year-old Western Hemlock stands in British Columbia, specifically examining the effects of commercial thinning over a 32-year period. The study found that while thinning did not significantly increase the overall cumulative yield, it did result in a larger average diameter for the remaining trees and an up to 8% greater usable total volume yield at the final harvest compared to unthinned stands. The decision to commercially thin these stands depends on whether a forester prioritizes a moderate increase in total volume or an improvement in the size and quality of the final harvested material.

This document details a 35-year study on the effects of commercial thinning on 50-year-old Douglas-fir stands on Vancouver Island. The study compared thinned and unthinned plots to analyze growth and yield metrics such as total volume, diameter, and mortality. While thinning led to a 12% increase in potentially usable total volume yield over the study period and produced larger diameter trees overall, it also resulted in an 18% reduction in total volume at final harvest compared to unthinned stands. The study suggests that commercial thinning provides earlier wood availability and larger trees, but does not significantly alter total gross annual growth or crop-tree size, offering valuable data for forest management models and strategies.

This document focuses on direct seeding as a reforestation method, offering a comprehensive analysis of its historical context, current efficacy, and future potential. The authors detail the merits of direct seeding, highlighting its ecological advantages, natural root system development, cost-effectiveness compared to planting seedlings, and operational benefits for large, remote, or low-budget restoration projects. Despite these advantages, the review examines current research findings which consistently show low seedling establishment rates due to various limiting factors such as seed parameters, timing of seeding, inappropriate seeding practices, unfavorable microsite conditions, competitive vegetation, and significant seed predation. The document also provides a direct comparison between seeding and traditional seedling planting, generally concluding that planted seedlings exhibit higher survival and faster initial growth. Finally, it explores potential alternative direct seeding practices and technologies, like seed shelters and drone-based delivery systems, that aim to overcome existing challenges and enhance the success rates of this method for global forest restoration efforts.

This article explores the ecophysiological factors influencing seedling establishment in forest restoration efforts. It examines how a seedling's morphological and physiological characteristics interact with environmental conditions on restoration sites, ultimately determining its success. The article explores how light, temperature, and water availability affect seedling performance, highlighting the challenges posed by extreme conditions like frost or drought and the benefits of optimal growing environments. The critical role of nutrient cycling and competitive vegetation is also discussed, emphasizing that a comprehensive understanding of these interactions is key to applying effective silvicultural practices that maximize seedling growth and ensure rapid forest stand establishment.

This manual outlines the comprehensive process for implementing commercial thinning operations in British Columbia, driven by the need to address fiber shortages caused by natural disturbances. The document is structured to guide various users, from forest planners selecting appropriate stands and assessing economic viability, to field supervisors and machine operators executing the thinning process. It details crucial stages including identifying suitable stands based on specific criteria like species and age, meticulous planning at the block level encompassing pre-harvest assessment and selecting optimal harvesting systems, and the practical implementation with an emphasis on coaching operators and diligent monitoring. The manual also highlights the importance of post-harvest assessment and considers broader implications, such as the long-term impact on timber supply and the integration of non-timber values like wildlife habitat and wildfire risk reduction.

This document serves as a comprehensive manual for forest professionals, outlining best practices for thinning operations effective April 2025. Its primary purpose is to support sustainable forest management by providing science-based guidelines for developing and implementing thinning prescriptions, particularly for enhancing timber production and quality. The guidance emphasizes maintaining ecological and social objectives while focusing on operational efficiency, minimizing environmental impacts, and promoting innovative approaches. It also details the required data collection and monitoring processes to ensure the effectiveness and compliance of thinning activities, thereby fostering healthy, resilient forest ecosystems across British Columbia.

This document introduces revised estimates for snow recovery in pine-dominated forests of British Columbia's interior, a critical factor for watershed management. Snow recovery refers to the restoration of snow accumulation and melt patterns in regrowing forests after clearcutting, compared to mature forests and clearcut areas. The authors highlight how changes in forest cover significantly impact spring streamflow peaks, making accurate recovery estimates essential for assessing potential hydrologic changes. The study presents new recovery curves based on long-term data from the Thompson-Okanagan region, demonstrating that previous estimates likely overstated the rate of snow recovery, suggesting a more gradual return to pre-harvest conditions as young forests grow taller.

This paper presents the 8-year results of a silvicultural systems trial at Lucille Mountain in British Columbia's Engelmann Spruce-Subalpine Fir zone. The study investigates the effects of different logging methods like clearcutting, patch cutting, and various partial cuts on climate, regeneration, tree growth, wind damage, arboreal lichens, and litter decomposition. The research highlights the complex environmental responses to forest harvesting in this high-elevation ecosystem and provides initial insights for better managing these sensitive forests, including considerations for reforestation practices and the challenges of adaptive management.