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Log logistics include sorting, processing, and transporting of logs from their place of harvest to demand locations. These activities account for a significant portion of the total log procurement costs; therefore, attempts were made in previous studies to optimize some aspects of log logistics. However, operational details, such as sorting decisions, truck compatibility requirements, and social objectives, are often disregarded in the optimization literature. Incorporating these details into the model makes the results more realistic and applicable. To address these gaps, a bi-objective mixed-integer programming model is developed in this paper to optimize log logistics. The first objective is to minimize total logistics costs, and the second objective is to provide a balanced workload for trucking contractors. The bi-objective model is solved using the goal programming approach. The model is applied to log logistics of a large Canadian forest company, where trucking contractors use heterogeneous fleet of trucks to carry various log sorts from cutblocks to sort yards for sorting. The planning horizon is 4 weeks with daily decisions. The goal programming model generates balanced workloads for the contractors with less than 0.4% increase in total costs compared to the single objective model where only the total cost is minimized. Key words: log logistics, goal programming, bi-objective optimization, social objective, sorting decisions, compatibility requirements. La logistique des rondins inclut le tri, le traitement et le transport des rondins a partir du lieu de leur recolte jusqu'aux lieux ou il y a une demande. Ces activites representent une partie importante des couts totaux de l'approvisionnement en rondins et, par consequent, des tentatives ont ete faites dans des etudes anterieures pour optimiser certains aspects de la logistique des rondins. Toutefois, les details operationnels, par exemple les decisions de tri, les exigences de compatibilite des camions et les objectifs sociaux, sont souvent ignores dans la documentation sur l'optimisation. L'integration de ces details dans le modele rend les resultats plus realistes et plus applicables. Pour combler ces lacunes, un modele de programmation d'entier relatif mixte bi-criteres d'optimisation est developpe dans la presente communication dans le but d'optimiser la logistique des rondins. Le premier objectif est de minimiser les couts totaux de la logistique et le second objectif est de fournir une charge de travail equilibree aux entrepreneurs en camionnage. Le modele bi-criteres d'optimisation est resolu en utilisant une approche de programmation des objectifs. Le modele est applique a la logistique des rondins d'une importante compagnie forestiere canadienne oU les entrepreneurs en camionnage utilisent une flotte heterogene de camions pour transporter diverses sortes de rondins a partir des blocs de coupe jusqu'aux parcs de triage pour y etre tries. L'horizon de planification est de 4 semaines avec des decisions quotidiennes. Le modele de programmation des objectifs genere des charges de travail equilibrees pour les entrepreneurs avec une augmentation des couts totaux de moins de 0.4 % comparativement au modele a objectif unique oU seulement le cout total est minimise. [Traduit par la Redaction] Mots-cles : logistique des rondins, programmation des objectifs, optimisation bi-criteres, objectif social, decisions de tri, exigences de compatibilite., 1. Introduction Log logistics include sorting, processing, transporting, and storing logs. Overall, these activities make up a large proportion of the total log procurement costs. An important element of log [...]

Forestry is an important component of Canada's economy with British Columbia (BC) contributing almost half to the national roundwood production. Yet, the country's timber supply and forest economy are threatened by climate change, with increased frequency and severity of natural disturbances and changes in forest productivity. Mountain pine beetle (Dendroctonus ponderosae) outbreaks are endemic in BC, but the latest climate change-driven outbreak has resulted in a cumulative loss of over half of all merchantable pine, leading to a mid-term timber supply shortage. In this study, we investigate the potential of commercial thinning and alternative planting regimes based on species diversification and assisted species migration to mitigate the anticipated decrease in timber supply in BC. We simulated the long-term effects of these management options in a case study area in interior BC, using a toolbox that combines management- and research-oriented data and models. We found that combining commercial thinning and species diversification has the best potential to mitigate future timber supply shortages in BC. We discuss the limits of this toolbox approach and identify research needs and recommendations for future studies aiming at modelling cumulative effects of management, climate change, and natural disturbances on timber supply. [ABSTRACT FROM AUTHOR]

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The competitiveness of forest companies is strongly affected by the costs associated with getting the raw material to the mills. As harvesting costs contribute significantly to this cost, mathematical programming models were developed to optimize the scheduling of harvest activities within and between cut blocks to reduce the overall cost. However, the precedence relationship between harvesting activities occurring concurrently across multiple cut blocks has not been considered in the existing literature. In this paper, a mixed-integer linear programming model is developed to optimize the scheduling of harvesting activities, considering the precedence relationship among harvesting activities. The objective of the model is to minimize the total costs. The model determines the start time and end time of each harvesting activity at each cut block, considering the movement time of machines between cut blocks. The model is applied to the case of a large forest company in British Columbia, Canada. The model's harvesting cost is only 1.37% higher than the lowest possible harvesting cost, and only 3 assigned machines have an idle time. The detailed harvesting schedule is generated based on the start time, the end time, and the operating time for each activity at each cut block. [ABSTRACT FROM AUTHOR]

Applied educational opportunities in forestry undergraduate curricula are essential for a complete postsecondary degree program. Walking distance to local urban forests present a way to teach forestry students in applied settings, while reducing the time, cost, and travel logistics. A case study at a Canadian university (University of British Columbia) was used to connect urban forest canopy cover to forestry learning objectives and walking time to the main teaching building. Individual tree canopies were identified with light detection and ranging data and aggregated to 0.05 ha grid sections. Using canopy cover and forest arrangement, the urban forest was classified into closed, open, small, sparse, or non- forest classifications. Forestry learning objectives were matched with each forest classification in conjunction with walkability to identify critical local location for forestry education. Results identified key areas suitable for teaching forestry and for linking forestry educational values with easily accessible high value locations. [ABSTRACT FROM AUTHOR]

Changing climates are altering the structural and functional components of forest ecosystems at an unprecedented rate. Simultaneously, we are seeing a diversification of public expectations on the broader sustainable use of forest resources beyond timber production. As a result, the science and art of silviculture needs to adapt to these changing realities. In this piece, we argue that silviculturists are gradually shifting from the application of empirically derived silvicultural scenarios to new sets of approaches, methods and practices, a process that calls for broadening our conception of silviculture as a scientific discipline. We propose a holistic view of silviculture revolving around three key themes: observe, anticipate and adapt. In observe, we present how recent advances in remote sensing now enable silviculturists to observe forest structural, compositional and functional attributes in near-real-time, which in turn facilitates the deployment of efficient, targeted silvicultural measures in practice that are adapted to rapidly changing constraints. In anticipate, we highlight the importance of developing state-of-the-art models designed to take into account the effects of changing environmental conditions on forest growth and dynamics. In adapt, we discuss the need to provide spatially explicit guidance for the implementation of adaptive silvicultural actions that are efficient, cost-effective and socially acceptable. We conclude by presenting key steps towards the development of new tools and practical knowledge that will ensure meeting societal demands in rapidly changing environmental conditions. We classify these actions into three main categories: re-examining existing silvicultural trials to identify key stand attributes associated with the resistance and resilience of forests to multiple stressors, developing technological workflows and infrastructures to allow for continuous forest inventory updating frameworks, and implementing bold, innovative silvicultural trials in consultation with the relevant communities where a range of adaptive silvicultural strategies are tested. In this holistic perspective, silviculture can be defined as the science of observing forest condition and anticipating its development to apply tending and regeneration treatments adapted to a multiplicity of desired outcomes in rapidly changing realities. [ABSTRACT FROM AUTHOR]