Derek Sidders

A bioeconomic approach to assess the impact of an alien invasive insect on timber supply and harvesting: a case study with Sirex noctilio in eastern Canada

This study presents a model that assesses the potential impact of a new alien insect species, Sirex noctilio Fabri- cius, on pine timber supply and harvest activities in eastern Canada. We integrate the spread of S. noctilio with a broad-scale growth and harvest allocation model. Projections of pine mortality range between 25 � 10 6 and 115 � 10 6 m 3 over 20 years depending on S. noctilio spread and impact assumptions. Our model suggests Ontario could experience the highest, most im- mediate losses (78% of the potential losses across eastern Canada), with Quebec sustaining most of the rest of the losses over the next 20 years. Potential losses of

Wood fibre value simulation model: a new tool to assist measuring changes in forest landscapes by evaluating forest inventory

86 to

Effect of utilization standard on wood supply and lumber yield

254 million per year are simulated after 20 years. The net present value of total harvest losses after 28 years of outbreak ranges between

Accelerating the selection process for Populus and Salix clones using short-term photosynthetic acclimation responses under greenhouse conditions

0.7 to

Modeling lumber yield of white spruce in Alberta, Canada: a comparative approach

2.1 billion. Adaptation policies decrease short- term losses by 46%-55% and delay larger harvest failures by 9-11 years. Without harvest adaptation, failures to maintain annual allowable cut levels may occur once the total area infested exceeds 15 � 10 6 ha. While better understanding and rep- resenting S. noctilio behaviour will involve a significant effort, there is a strong demand by policy makers for this kind of in- formation.

Short-term growth and morphological responses to nitrogen availability and plant density in hybrid poplars and willows

ContextA challenging issue in landscape ecology is the evaluation of changes in a forest landscape following a disturbance. This evaluation usually entails examining changes in the forest inventory, which represents the best information available for a given forest region.ObjectivesOur aim was to extend existing methods used to evaluate forest inventory to include additional variables, such as value-based forest product options, wood fibre attributes, and ecosystem services. Inclusion of such variables in forest inventory evaluations would allow research results to be presented from an economic perspective, which is often required for policy development and forest management decision-making.MethodsWe developed a value-based framework to evaluate forest inventory and implemented it in the wood fibre value simulation model. We then used a local data set from Manitoba, Canada, to show how the model can be applied to the mapping of new inventory layers to facilitate the evaluation of landscape changes.ResultsFive new inventory layers are mapped including bioenergy and heating value that can be directly used for evaluating landscape changes, and wood density, fibre length, and pulp yield, which can be combined with total wood volume to derive new variables or indices to express changes in landscape conditions.ConclusionsOur model can contribute to the assessment of landscape changes by indicating the values a forest can have when it is used for different conservation or utilization purposes. The model can also support improved decision-making with respect to the management of forest resources.

Research on hybrid poplars and willow species for fast-growing tree plantations: Its importance for growth and yield, silviculture, policy-making and commercial applications

ABSTRACT Although sustainable forest management is accepted worldwide in concept, challenges in the methods of implementation remain. Using local data sets from Alberta, Canada, we show that a simulation approach can assist the implementation of sustainable forest management by improved understanding of product potential and other forest ecosystem goods and services that forests can provide for a given forest inventory. This will assist facilitating trade-offs among them for an optimal wood utilization strategy to achieve sustainable forest management. In this example, effects of wood utilization standard on merchantable volume, lumber volume, and number of trees that can produce at least one piece of lumber are quantified, and a conversion method for wood volumes under different wood utilization standards is presented. Wood utilization standard is the combination of stump height and diameter inside bark at merchantable height, which considerably influences available volume quantity of forest resource. However, such influences have not been quantified for sustainable forest management implementation. Our results not only confirmed that merchantable and lumber volumes increased with decreasing stump height and diameter inside bark at merchantable height, but also revealed that this trend will not hold when diameter inside bark at merchantable height is less than 7 cm.

A harvest failure approach to assess the threat from an invasive species.

ABSTRACT Leaf photosynthetic characteristics could be determinant factors to identify the most productive clones of hybrid poplars (Populus spp.) and willows (Salix spp.). Photosynthetic acclimation of hybrid poplars and willows was studied under greenhouse conditions. Seven Populus and five Salix clones were grown for 3 months at three spacings [20 × 20, 35 × 35, and 60 × 60 cm] and two nitrogen (N) levels (20 and 200 µg g-1). There were no significant spacing effects on leafless aboveground biomass per tree (AGBT) and height. Clonal acclimation to higher density was associated to increases in leaf area index (LAI) by 347% and specific leaf area (SLA) by 13% despite decreased leaf N content per unit leaf area (Narea) by 31%. There were no changes in net CO2 assimilation rate (A) and photosynthetic N-use efficiency in the ambient light condition (PNUEamb) within different spacings. The N addition alleviated competition effects by maximizing leaf area (LA) and SLA. Compared with less productive clones, more productive clones had 28% greater SLA, greater LA and AGBT per unit of increase in Narea over all treatments. The increased development of LA and SLA under high planting density is a key indicator of more productive clones.

Evaluating sampling designs and deriving biomass equations for young plantations of poplar and willow clones.

Estimation of lumber yield from a forest inventory is important in determining the optimal utilization of available regional wood supply. In this study, we review existing approaches of lumber yield estimation, including knowledge-based empirical board-foot log rules used in the United States and some regions of Canada, survey-based wood conversion factors, and optimization technology-based computer simulations. Lumber yields estimated from different approaches are then compared using six datasets from a white spruce commercial thinning experiment in Alberta, Canada. Our results indicated that (1) estimated lumber yield can be significantly different when different methods are employed; (2) board-foot log rules often underestimate lumber yield; (3) wood conversion factors represent regional average of lumber yield as a constant and thus are unsuitable for forest inventory-based lumber yield estimation; and (4) optimization technology-based computer simulations can provide the best estimate of lumber yield for a given forest inventory as long as the mill conditions and lumber dimensions from market demand are specified. Forestry investment in applying computer simulation methods should be encouraged in sawmill operations to improve lumber yield and enhance environmental protection, because, for a given amount of lumber, improving lumber yield means reduced demand for harvest operations.