Publications - Silviculture

Characterization of knots in plantation white spruce

Fri, 05 Apr 2013

Knot size and distribution are of key importance to wood quality and lumber grade yield. This study characterized white spruce (Picea glauca [Moench] Voss) knots with computerized tomography images and knot mapping software. The characteristics included shape, number, diameter, inclination (angle between z-axis and the line connecting the knot’s starting point at the pith with the end point), azimuth direction, and distribution inside the stem. There were on average 112 grade-important knots per tree in a 32-yr-old plantation white spruce tree, 7% of which could downgrade lumber from Select Structural to No. 2 and lower grades. A total of 3.6% were ramicorn knots, and 70% had an inclination angle between 60 and 80° with the tree axis. There were 24 more knots per tree with every 2-cm increase in tree diameter. Knot diameters had a positively skewed frequency distribution with an average of 156 mm. The majority of the knots had a taper between 0.18 and 0.38 mm/mm, which could have had a major impact on lumber mechanical properties. Knots grew steeply upward until reaching their greatest diameters and became more horizontal afterward. Butt logs had smaller but a higher number of knots and a lower percentage of knot volume (out of log volume) than those higher up. In the same height growth unit, inclination angle decreased with increasing height. Wider knots had a smaller inclination angle.White spruce has a weak self-pruning mechanism and is prone to forking or ramicorn branching. The widest knot in a height growth unit is more likely to be found in the south direction. Trees from wider spacing tend to have wider knots but not necessarily a higher number of knots at the same heights. The results suggest the need for pruning operations and including knot information in determining sawing strategies. Information from this study should be useful in forest management decision-making and improving wood use.

Fast-growing tree plantations: a source of bioenergy. Branching out from the Canadian Forest Service, Laurentian Forestry Centre. No. 79.

Wed, 27 Mar 2013

Growth: a key issue.

Abitibi-Témiscamingue: an experimental land.

Greenhouse or field testing: a matter of time.

A growing phenomenon.

In Brief from the Canadian Forest Service, Laurentian Forestry Centre. No. 33.

Mon, 18 Mar 2013

Partial cutting in the boreal forest: the right choice for biodiversity.

Fire regimes have an influence on forest succession.

Heat causes release of CO² from forest soil.

Forest biomass: A good choice, if you know how to count.

Is there competition or mutual support between species in mixed stands?

Impact of biomass harvesting in boreal and temperate forests.

La recherche au Centre de foresterie des Laurentides de Ressources naturelles Canada – Les ravageurs forestiers exotiques.

Tue, 02 Apr 2013

By definition, exotic forest pests are diseases or insects that are present outside of their natural range. They are described as "invasive" when they alter the ecosystems into which they are introduced. According to Canadian Forest Service (CFS) researchers, more than 80 exotic pests harmful to Canada's forests have become established here since 1882. This brochure describes the main exotic pests that are currently being studied at the Canadian Forest Service's Laurentian Forestry Centre (LFC).

Les Brèves du Service canadien des forêts, Centre de foresterie des Laurentides. No 33.

Mon, 18 Mar 2013

Partial cutting in the boreal forest: the right choice for biodiversity.

Fire regimes have an influence on forest succession.

Heat causes release of CO² from forest soil.

Forest biomass: A good choice, if you know how to count.

Is there competition or mutual support between species in mixed stands?

Impact of biomass harvesting in boreal and temperate forests.

Plantations d’espèces à croissance rapide : une source de bioénergie. L’éclaircie du Service canadien des forêts, Centre de foresterie des Laurentides. No 79.

Wed, 27 Mar 2013

Growth: a key issue.

Abitibi-Témiscamingue: an experimental land.

Greenhouse or field testing: a matter of time.

A growing phenomenon.

Research at the Laurentian Forestry Centre of Natural Resources Canada – Exotic forest pests.

Tue, 02 Apr 2013

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

Fri, 08 Mar 2013

There is a growing interest in fast-growing hybrid poplar and willow plantations in Canada. This interest can be explained both by the rapid growth rate and high yield potential of this type of production system. However, their establishment and maintenance require considerable investments. Research efforts on productivity comparisons between different clones or species, breeding, physiology, nutrition, silviculture, pest management, harvesting methods, social and economic issues and industrial transformation contribute to maximizing fibre production and minimizing production costs. The objective of this paper is to briefly describe a number of current or recently completed research studies on fast-growing hybrid poplar and willow plantations and to discuss their utility and impacts for practical applications.

The economic attractiveness of short rotation coppice biomass plantations for bioenergy in northern Ontario.

Wed, 13 Feb 2013

With an apparent abundance of idled and under-utilized agricultural land in Northern Ontario, there is interest in the ability of short-rotation forests to supply bioenergy and other possible bioproducts. Once established, Short Rotation Coppice (SRC) plantations can be harvested on (roughly) three-year cutting cycles until about age 22. Purpose-grown plantations such as these could be used as stand-alone sources of fibre or used in conjunction with sources such as natural forests or woody residues. Using a recently developed land cover model we found that approximately 405 500 ha of agricultural-type land exists across Northern Ontario. Numerous scenarios were developed to calculate SRC profitability on these areas. The analyses are intended to reflect a broad range of expectations on physical yields and prices, including management costs. Although SRC involves a considerable up-front investment, our simulations suggest a significant amount of land could have a break-even biomass price of $85/oven-dried tonnes (ODT) (+/- $5/ODT) at farm gate. This farm gate biomass price represents roughly current traditional biomass prices paid. Thus SRC would need to produce biomass at a comparable cost to be a competitive option. A number of technological and price changes could increase the attractiveness of SRC systems in Northern Ontario, including decreases in establishment and management costs (while maintaining yield expectations) and improved cultivars offering increased yields.

A decision-support model for regulating black spruce site occupancy through density management.

Fri, 21 Dec 2012

A silviculture application of the glyphosate-based herbicide Visionmax to wetlands has limited direct effects on amphibian larvae.

Fri, 21 Sep 2012

—Herbicides are commonly used in agriculture and silviculture to reduce interspecific competition among plants and thereby enhance crop growth, quality, and volume. Internationally, glyphosate-based herbicides are the most widely used herbicides in both of these sectors. Laboratory and mesocosm studies have demonstrated that some formulations are toxic to amphibian larvae below concentrations that approximate predicted maximal or ‘‘worst-case’’ exposure scenarios. However, field studies have not found evidence of toxicity at these concentrations. The authors conducted a replicated field experiment involving 10 naturalized wetlands split in half with an impermeable plastic barrier to assess the direct toxicity of a glyphosate formulation commonly used in silviculture (VisionMAXTM). The herbicide formulation was applied directly to the surface of one side of each wetland at one of two target aqueous exposure rates (high¼2,880, low¼550 mg acid equivalents [a.e.]/L), and the other side was left as an untreated control. The survival and growth of green frog larvae (Lithobates clamitans) were assessed for two years following herbicide treatment. The herbicide did not have a negative impact on survival or growth of L. clamitans larvae at either treatment level. In fact, mean larval abundance was typically greater in the treated sides than in control sides within the year of herbicide application. These results indicate that typical silviculture use of VisionMAX poses negligible risk to larval amphibians, likely because the combined effects of sorption and degradation in natural wetlands limit the exposure magnitude and duration.

Anatomie d’un élagage réussi. L’éclaircie du Service canadien des forêts, Centre de foresterie des Laurentides. No. 74.

Tue, 26 Jun 2012

Pruning is a very useful silvicultural treatment both for improving the final quality of a stand and for controlling certain pests. However, pruning causes wounds that the tree must close as quickly as possible. Knowing a few facts about free anatomy allows us to carry out this operation efficiently while preserving the tree's health.

Anatomy of a successful pruning. Branching out from the Canadian Forest Service, Laurentian Forestry Centre. No. 74.

Tue, 26 Jun 2012

Pruning is a very useful silvicultural treatment both for improving the final quality of a stand and for controlling certain pests. However, pruning causes wounds that the tree must close as quickly as possible. Knowing a few facts about tree anatomy allows us to carry out this operation efficiently while preserving the tree's health.

Annotated Bibliography on the Impact of Silviculture and Management on Wood Fibre Attributes for Eight Major Canadian Commercial Tree Species / Bibliographie annotée sur les répercussions de la sylviculture et de l’aménagement sur les caractéristiques de la fibre ligneuse de huit essences commerciales canadiennes importantes

Thu, 18 Oct 2012

This annotated bibliography contains 518 citations, mostly of North American and European origin. It focuses on the following eight species of commercial importance in Canada: white spruce (Picea glauca (Moench) Voss), black spruce (Picea mariana (Mill.) B.S.P.), jack pine (Pinus banksiana Lamb.), balsam fir (Abies balsamea (L.) Mill.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), lodgepole pine (Pinus contorta Dougl.), trembling aspen (Populus tremuloides Michx.), and sugar maple (Acer saccharum Marsh.). The focus of this research was to determine the impact of silviculture on a selected and key group of fiber attributes for fire-origin and second-growth stands.

Development and utility of an ecological-based decision-support system for managing mixed coniferous forest stands for multiple objectives.

Fri, 21 Dec 2012

Guide pour la sylviculture du thuya occidental. (THE ENGLISH VERSION OF THE GUIDE IS PUBLIC AND AVAILABLE AT: www.nrs.fs.fed.us/pubs/gtr/gtr_nrs98.pdf)

Wed, 14 Nov 2012

In Brief from the Canadian Forest Service, Laurentian Forestry Centre. No. 28.

Tue, 27 Mar 2012

Does fire severity affect the decomposition of woody debris?

Scleroderris canker: reinterpreting the historical record

Silviculture and regeneration of eastern white-cedar in mixedwood stands

Growing hybrid poplars outside their comfort zone

Evolution of the boreal forest in the absence of fire

Hemlock looper: more eggs, more parasitism?

In Brief from the Canadian Forest Service, Laurentian Forestry Centre. No. 30.

Tue, 28 Aug 2012

Identifying forests with an irregular structure.

Insect colonization of burned trees: A matter of chance?

Mountain pine beetle likely to benefit from climate change.

Winter survival not linked to host tree vigour.

Global warming has an adverse effect on old-growth boreal forests.

The hidden face of biomass.

In Brief from the Canadian Forest Service, Laurentian Forestry Centre. No. 31.

Wed, 24 Oct 2012

Hybrid Poplars and Hog Manure: A Profitable Combination.

Do warmer temperatures benefit hemlock loopers?

Is forest productivity slowed down by the reduction in forest fire activity?

Changes in mortality after boreal forest fires.

Is forest biomass a panacea?

From mouse-ear cress to spruce in a single step.

In Brief from the Canadian Forest Service, Laurentian Forestry Centre. Number 27.

Tue, 31 Jan 2012

The mountain pine beetle does not operate alone.

Reforestation of boreal forested peatlands.

Characterization of post-fire residual habitats.

Climate change: lichen woodlands to the rescue.

Good news for native poplars.

The pre-industrial forest landscape of Anticosti Island.

La rouille vésiculeuse du pin blanc : savoir, contrôle et innovation. L’éclaircie du Service canadien des forêts, Centre de foresterie des Laurentides. No. 73.

Tue, 26 Jun 2012

The essential link between Ribes spp. and blister rust.

Careful selection of planting sites.

Inspection and pruning to the rescue.

Planting blister rust-free seedlings: it's not that simple!

Increasing resistance through hybridization.

Les Brèves du Service canadien des forêts, Centre de foresterie des Laurentides. No 28.

Tue, 27 Mar 2012

Does fire severity affect the decomposition of woody debris?

Scleroderris canker: reinterpreting the historical record

Silviculture and regeneration of eastern white-cedar in mixedwood stands

Growing hybrid poplars outside their comfort zone

Evolution of the boreal forest in the absence of fire

Hemlock looper: more eggs, more parasitism?

Les Brèves du Service canadien des forêts, Centre de foresterie des Laurentides. No 30.

Tue, 28 Aug 2012

Identifying forests with an irregular structure.

Insect colonization of burned trees: A matter of chance?

Mountain pine beetle likely to benefit from climate change.

Winter survival not linked to host tree vigour.

Global warming has an adverse effect on old-growth boreal forests.

The hidden face of biomass.

Les Brèves du Service canadien des forêts, Centre de foresterie des Laurentides. No 31.

Wed, 24 Oct 2012

Hybrid Poplars and Hog Manure: A Profitable Combination.

Do warmer temperatures benefit hemlock loopers?

Is forest productivity slowed down by the reduction in forest fire activity?

Changes in mortality after boreal forest fires.

Is forest biomass a panacea?

From mouse-ear cress to spruce in a single step.

Les Brèves du Service canadien des forêts, Centre de foresterie des Laurentides. Numéro 27.

Tue, 31 Jan 2012