141 resources found

This FRDA Report #097 investigates the net basal area response of Douglas-fir trees to nitrogen fertilization in stands that have been thinned and unthinned. The research, based on a 9-year study in British Columbia, developed equations to predict how fertilization affects tree growth and focused on how thinning influences the effectiveness and longevity of fertilizer application. Key findings indicate that thinned stands show a greater and more persistent response to nitrogen fertilization compared to unthinned stands where the effect tends to dissipate more quickly. The study provides valuable insights for forest managers on optimizing silvicultural practices by combining thinning and fertilization to enhance Douglas-fir productivity.

This FRDA Report #137 investigates the basal area response of immature coastal western hemlock stands to fertilizing and thinning treatments on northern Vancouver Island, nine years after application. The purpose is to understand how these silvicultural practices affect tree and stand growth, particularly focusing on net basal area response, which is a measure of the cross-sectional area of tree trunks. The study found that while thinning alone significantly improved growth, the best results were achieved by combining fertilization with thinning, as this concentrated the additional growth onto fewer, more valuable stems, even though the total basal area removed by thinning was not fully recovered within the nine-year period. The research also provides equations for estimating net basal area response, offering practical tools for forest managers considering these interventions.

This LMH Document #59 outlines a management strategy for mule deer winter ranges specifically within the transition and deep snowpack zones of the Cariboo-Chilcotin region. It's structured in two main parts: the first details winter range management objectives, including long-term spatial goals, access considerations, and stand-level targets for forest structure and species composition, largely employing a group selection silviculture system. The second part provides guidance on planning forest harvests to align with these objectives, offering practical steps and a checklist for implementation, aiming to integrate timber harvesting with the maintenance and restoration of suitable mule deer habitat.

This FRDA Research Memo #210 details a study on the natural regeneration of Engelmann Spruce and Subalpine Fir following clearcutting in southern British Columbia at high elevations. The study analyzed two years of data across multiple clearcut sites, investigating how factors like moisture regime, treatment type, and slope aspect affected the resulting stocking and growth of the seedlings. Key findings included that regeneration was generally successful, though sites with higher moisture and those facing south had better stocking, and that treatments that promoted mineral soil exposure significantly increased seedling density and growth for both species. The document offers management implications, suggesting that reliance solely on natural regeneration at high elevations may require reassessing expected timelines for regrowth.

This FRDA Research Memo #218 investigates the effectiveness of various mechanical site preparation methods, specifically disc trenching, patch scarification, and ripping, on the establishment of conifer seedlings across three different biogeoclimatic subzones in British Columbia's interior. The study sought to determine the optimal mechanical treatment and the most favorable microsite planting positions for seedling survival and growth, particularly focusing on mitigating frost damage. After five years, results consistently showed that disc trenching and ripperdrag treatments offered the best outcomes across the subzones, with the specific microsite preference varying based on site moisture and elevation to best protect against environmental stressors like frost and drowning.

This FRDA Research Memo #219 provides preliminary guidelines for conducting modified commercial thinning operations in coastal British Columbia forest stands grappling with laminated root rot, a pervasive disease caused by the native fungus Phellinus weirii. The disease reduces forest productivity by causing mortality, slowing growth, and predisposing trees to windthrow, and traditional thinning practices have intensified its spread. The modified commercial thinning operations involve first identifying and mapping LRR infection centers, then harvesting all susceptible trees within a specific disease buffer zone surrounding these centers, which are known as bridge trees, to isolate the infection and contain its spread. This research aims to validate predictive forest models and refine management strategies for balancing commercial logging viability with disease mitigation in afflicted areas.

This FRDA Research Memo #241 details a study in the North-Central Interior of British Columbia comparing the effects of different site preparation treatments on the growth of lodgepole pine and hybrid white spruce seedlings. The research specifically investigated broadcast burning, disc trenching, pile-and-burn, and no treatment, analyzing their impact on soil conditions and seedling performance, including height and root growth after multiple growing seasons. Key findings indicated that disc-trenching and broadcast burning were the most effective methods for improving growth by enhancing soil properties, whereas the pile-and-burn treatment sometimes led to detrimental soil compaction due to excavator tracks, which hindered root development. Although site preparation was not necessary for high seedling survival on this particular wet, cool site, certain treatments were clearly beneficial for maximizing growth.

This study documents the Montane Alternative Silvicultural Systems project, a long-term cooperative study on Vancouver Island, British Columbia, established to find forest management practices that could replace conventional clearcutting in high-elevation coastal environments. This research initiative evaluated the operational, economic, and biological consequences of alternatives like patch cuts, green tree retention, and shelterwood logging. The findings cover crucial metrics such as operational costs and feasibility, as well as detailed ecological and silvicultural impacts on forest regeneration, soil health, and local biodiversity. The purpose of the MASS research was to provide the scientific foundation needed for implementing environmentally sustainable harvesting systems, such as variable retention, in the region's complex montane forests.

This paper examines the complex relationship between forest health and climate change from a British Columbia perspective, building on the impact of past events like the mountain pine beetle and Dothistroma needle blight epidemics. The authors present estimations of how various forest pests are expected to behave as climate continues to change, emphasizing that rapid environmental shifts are favoring fast-reproducing pests over long-lived trees. The research offers management recommendations aimed at increasing forest resilience, such as implementing assisted migration and genetic diversity, while stressing that the future of forest management requires flexibility and adaptation in the face of unprecedented uncertainty. The purpose of this paper is to equip managers with projections for the near future and emphasize the urgency of integrating proactive forest health measures into all aspects of land-use planning.

This technical report investigates the potential of variable retention silvicultural systems to manage forests in British Columbia's Nelson Forest Region, aiming to mitigate anticipated reductions in wood supply due to new environmental regulations. The study specifically evaluates how different variable retention methods impact stand productivity and overall wood flow despite the widespread presence of Armillaria root disease. Using the PROGNOSIS growth model, the authors identify low-risk timber types and develop management guidelines to balance timber harvesting with objectives like biodiversity and visual quality and reccomend a more balanced mixture of clearcutting and variable retention approaches to ensure sustainable forest management.

This webinar outlines a successful ten-year effort to refine reforestation techniques using post-harvest slash burning in Minnesota after a large-scale jack pine budworm salvage operation. While initial attempts tried to use fire and direct seeding for complete restoration, the team discovered that the prescribed burns were most effective when used as a tool for controlling aggressive woody competition like aspen. Experience taught the team that achieving deep root-kill and effective brush control depends on conducting burns during late summer dry soil conditions, which is crucial for maximizing intensity. The resulting methodology integrates fire as a hybrid replacement for chemical herbicide application, successfully preparing sites for planting and promoting the establishment of diverse jack pine stands.

This webianr explored the use of biochar as a promising but highly variable soil amendment intended to enhance forest climate resilience, focusing on its potential for increased water holding capacity and long-term carbon storage. Lead researcher, Marcelo Windmuller-Campione, detailed multiple collaborative studies, primarily testing biochara?Ts effectiveness on Jack Pine survival and growth in Minnesota's porous, sandy soils. While initial benefits were sometimes observed in early field trials, long-term data and controlled experiments indicated that the biochar provided no significant or lasting improvement compared to control groups. The research concluded that while biochar presents a viable carbon storage strategy, its operational feasibility and ecological benefits are severely limited when applied to highly porous forest ecosystems.

This document details the Montane Alternative Silvicultural Systems study, which investigated various forest harvesting methods to find ecologically sound alternatives to traditional clearcutting practices in high-elevation coastal forests. The seven-year results demonstrated that the fastest volume growth for regenerating western hemlock and amabilis fir occurred in the treatments with the least retained overstory, such as the clearcut and patch cut systems. The study also emphasized that effective control of competing vegetation is vital for successful seedling performance, noting that herbicide use yielded significantly better growth than manual clearing. The data suggested that silvicultural systems retaining a significant canopy might reduce long-term tree growth due to increased competition and lower light levels.

This technical report details the outcomes of the Montane Alternative Silvicultural Systems study, which was prompted by operational concerns about forest regeneration and public pressure to limit clearcutting in high-elevation coastal regions of British Columbia. The core objective was to compare the operational productivity and financial viability of three alternative harvesting techniques including uniform shelterwood, green tree retention, and patch cutting against a conventional clearcut. The findings indicated that while these innovative systems could be applied successfully on gentle terrain, they resulted in significantly higher harvesting costs, with the shelterwood system proving to be 38% more expensive than clearcutting. The report also examined the acceptable low levels of site disturbance and soil compaction caused by the machinery, confirming that long-term success will rely on future monitoring of windthrow occurrence and regeneration success.

The Montane Alternative Silvicultural Systems trial was designed to compare the ecological effects of traditional clearcutting against alternative silvicultural systems regarding forest nutrient dynamics in coastal British Columbia. Researchers observed that while harvesting led to a slight, short-lived increase in soil nitrogen availability, the resulting fluxes of nitrogen below the rooting zone were negligible. A key finding was that mineralized nitrogen remained predominantly in the form of ammonium, and subsequent nitrate increases were primarily due to decreased microbial consumption rather than increased production. The study concluded that since the estimated nitrogen losses from the rooting zone were minimal compared to vast soil reserves and natural atmospheric inputs, harvesting is unlikely to negatively impact future site productivity.

This report details the 26-year results of the Montane Alternative Silvicultural Systems Project, an integrated, long-term study designed to evaluate the biological consequences of different harvesting approaches in montane coastal forests of British Columbia. Researchers quantified changes in understory vegetation cover, diversity, and conifer regeneration across four systems, including clearcutting and various forms of tree retention, compared to an old-growth benchmark. The study found that while all harvesting methods led to an eventual increase in overall species richness, the uniform shelterwood retained more stand structure and pre-harvest plant species initially. The findings suggest that the retention of relatively intact mature forest patches is the most effective approach for conserving plant and non-vascular species associated with older forests.

This research documents a six-year monitoring study at the Montane Alternative Silvicultural Systems site, examining how different harvesting methods influence the likelihood of windthrow damage in coastal montane forests. The study quantified stem loss across four treatments, including clearcut, shelterwood, green tree retention, and patch cut, finding that windthrow losses were substantial across the site, which was not initially considered high risk. Although low-density green tree retention experienced the highest proportion of damaged trees, the overall greatest number of wind-damaged stems occurred in the shelterwood treatment. The data indicates that small, concentrated patch cuts resulted in the lowest amount of windthrow, suggesting that grouped retention is a more effective strategy than dispersed retention for minimizing wind damage. The authors conclude that adopting group retention strategies can better conserve structural forest elements while addressing challenges related to windthrow risk.

This document on the 26-year assessment of the Montane Alternative Silvicultural Systems evaluates the success of planted Amabilis fir and Western Hemlock seedlings established in 1994. The core purpose of the MASS study is to measure the impact of four distinct establishment treatments, including control, fertilization, herbicide, or a combination, on tree growth over time. These treated plots are systematically mapped within the context of various silvicultural harvesting systems, including clearcut, green tree, patch cut, and shelterwood. The images act as an inventory, identifying the specific plot numbers selected for the 2019 photographic evaluation of the long-term experimental outcomes within each system.

This document on the 26-year assessment of the Montane Alternative Silvicultural Systems study focuses on natural regeneration and understory species within various managed forest environments. The MASS study is highly structured, comparing distinct silvicultural systems such as clearcut, shelterwood, and old growth by utilizing three separate replicates for each treatment type. Data collection relies on establishing Permanent Vegetation Plots, which incorporate smaller, precisely defined nested sub-plots to monitor detailed plant life, including herbs, bryophytes, and tagged conifer species like Amabilis fir and Western Hemlock. These images function as a structured index, associating specific plot and photo numbers with each experimental manipulation across the research site.

This comprehensive 15-year report details the Montane Alternative Silvicultural Systems Project, which tested the efficacy of different harvesting treatments, including clearcutting, patch cutting, and various forms of retention, on forest health and regeneration in coastal British Columbia. Key findings reveal that while conifer survival remained consistent across treatments, tree height and volume growth was generally slower in the shelterwood environment due to reduced light, and the single most effective way to boost planted tree growth was through intensive vegetation control. Conversely, the shelterwood system successfully maintained the greatest understory species diversity and composition most similar to the uncut old-growth forest, minimizing the loss of shade-loving plants. The long-term data emphasizes a crucial trade-off: maximizing early conifer growth favors more open treatments, but retaining pre-harvest biodiversity values is best achieved with substantial canopy protection.