bluuebunny/crossref_metadata_2025 huggingface dataset:
Woodland caribou: Facts for forest managers
Authors: Cumming H. G.
Published: February 2014

A literature review points to predation as the proximate factor controlling woodland caribou (Rangifer tarandus caribou) populations in most cases, but that finding does not obviate the need for caribou to be included in forest management. Managers must consider the indirect effects of forest operations on caribou through their impacts on caribou mortality factors, such as prédation. Lichens remain important. Habitat destruction may in some cases be the ultimate cause of population decline. Reactions of caribou to disturbance vary, and remain controversial; more research is needed. Multiple resource managers of boreal commercial forests should identify sensitive components of caribou range – calving grounds, rutting locations, wintering areas, and travel routes among them – and prescribe for these areas in forest management plans. Ways of accommodating caribou in commercial forests are not well established, but some examples suggest how this might be done. Most importantly, areas that have been proven by their continued use to contain all necessary requirements for caribou survival should not be physically altered until their essential qualities and functions are better understood. Key words: Rangifer tarandus caribou, woodland caribou, predation, forest management.
Observations sur la tolérance aux embruns salins d'espèces ligneuses en plantation aux abords des autoroutes
Authors: Beaudoin Roger
Published: February 2014

Tolerance to de-icing salt was evaluated, 15 years after plantation, for 32 coniferous species along an expressway and an interchange. Observations show that damages to trees result mainly from spindrifts caused by passing vehicles. Trees planted closest to spindrifts are generally more affected. At the same distance from the pavement and for the same species, damage is more important in the plantations located close to expressways compared to those located close to interchanges. This variation seems to be a function of the estimated quantity of salt spread on the pavement, of the daily number and speed of vehicles and of wind speed. Browning of needles during spring and reduction of the foliar mass in the affected part of the tree contribute to the reduction of the photosynthetic capacity of the trees which is characterized, according to the species and its localization, by a more or less important reduction of total height growth at a given age. The limited number of repetitions does not allow detection of any difference between provenances of various species for their resistance to salt spindrifts. Among species included in this test, Picea pungens and Picea engelmannii are the most tolerant to salt spindrifts when located close to the expressway, at an average distance of 17 m from the pavement. This study shows that the choice of species for their tolerance to salt spindrifts is important if more efficient and more aesthetic plantations are to be established for windbreaks or ornamentation along expressways. Key words: expressway, de-icing salt, conifer plantation, salt tolerance, height growth.
A case study in spatial wood supply analysis
Authors: Jordan G. A. , Baskent E. Z.
Published: February 2014

This paper shows the effects of extraction economics and wildlife habitat values on wood supply for a 9,640 stand forest in New Brunswick. Using a spatial wood supply model developed at the University of New Brunswick, the paper quantifies and explains wood supply effects of harvest blocking, road cost and harvest adjacency delay. Eight spatial strategies test harvest scheduling based on geographic forest structure (distribution of stand developmental types and stages). Given a forest of mostly regenerating and mature developmental stages, wood supply reductions vary from 4.9% to 19.2% when compared to a convention aspatial assessment. The paper presents and explains reductions for all eight spatial strategies; but concludes that all are explained by the impacts that harvest blocking, road cost, or harvest adjacency delay have, singly, or in combination, on either mortality losses or the rate at which harvesting recycles forest area. Key words: Forest management, forest dynamics, GIS, wildlife, simulation, wood supply, harvest scheduling
Twenty-five years' growth in a young red pine stand
Authors: Newnham R. M.
Published: February 2014

Growth data are presented by 5-year intervals from age 20 to 45 years for a natural stand of red pine (Pinus resinosa Ait.) in eastern Ontario. At age 45 years, the top height (100 largest trees/ha) was 21.3 m and the volume 448 m3/ha, with little evidence of any decline in either height or volume growth. Site index was approximately 24 m (at age 50 years) which is considerably superior to Plonski's site class 1 (Plonski 1974). Growth appears to be comparable to that of unmanaged plantations growing on the best sites on the Petawawa Research Forest. Height-diameter regressions are calculated for each plot measurement and compared with a combined regression for all plot measurements. The Weibull function was used to fit diameter distributions.
Global perspectives and impacts on Canada's environment
Authors: (Bert) Reid E. S.
Published: February 2014

The greatest threat to the future world environment is that of the uncontrolled population increase and the resulting severe land and air degradation. Global population in 1990 was estimated at 5.3 billion, and is expected to double to 10 billion early in the next century. The UN Population Fund Report of 1990 stated "we cannot solve the environmental crisis without solving the population crisis". An equal danger to a stable and acceptable global environment are the excessive demands and wasteful use of resources by the Western world's society. Twenty-five percent of the population uses 80% of the worlds resources. Some authorities state that "the impact of each Canadian on the environment is the equivalent of that of 40 to 50 third world residents." Canada will be increasingly impacted by these global environmental issues whether we like it or not. The greatest threat will be that we do not recognize this fact and that we do not prepare ourselves for sustained resource use. However, there are great opportunities for Canadian resource planners and users to play a leading role in adopting a sustained, long term forestry vocation in respect of the use of all its resources; and demonstrate to the global community how essential this is for a stable economy, a moderate lifestyle, and a protected environment. We have the technological capability and the proven expertise to achieve this, if we care to use it appropriately. The major task is "selling" this integrated sustained use or sharing concept to Canadian society because of the required sacrifices in lifestyles, economic costs, and certain environmental degradation. In the short term, progress can be made with public input to commissions, hearings and the like; but in the long term, a rational understanding of sustained forest use and conservation can only be achieved through education in all forms at all ages. An appreciation of global forest and related environmental issues, and their impacts on Canada, can facilitate positive Canadian action to practical sustained use of all forest and natural resources, in both a national and global context.
Fire hazard in budworm-killed balsam fir stands on Cape Breton Highlands
Authors: Péch Gyula
Published: February 2014

The forests subject to budworm attack in eastern Canada vary considerably in tree species composition, and the severity of fire weather in those regions also varies. It is likely, therefore, that fire hazard or fire potential in budworm-damaged forest has complex causes. A forest of mixed conifers near the Aubinadong River in central Ontario represents probably one extreme situation, that of an abundance of combustible surface and aerial fuels coupled with high fire weather severity. This has resulted in many fires that are difficult to control. Then there are the pure and mature balsam fir stands of the Cape Breton Highlands in Nova Scotia, which have no apparent fire history and represent the other extreme: no accumulation of combustible surface fuels and low fire weather severity. A systematic study was undertaken between 1979 and 1988 in the Highlands, following a major budworm epidemic in the 1970's, to measure fire hazard quantitatively by monitoring changes in fuel distribution, and to evaluate fire weather severity and its seasonality. The results indicate that the cool and moist climate of the Highlands decomposed dead fuels rapidly, and there was little accumulation of surface combustibles. Furthermore, fire weather severity is low, and even when an unexpected drought occurs, direct attack and attainment of control of wildfire in these stands can be achieved with existing resources.
Length of the fire season in a changing climate
Authors: Wotton B. M. , Flannigan M. D.
Published: February 2014

The Canadian Climate Centre's General Circulation Model provides two 10-year data sets of simulated daily weather for a large array of gridpoints across North America. A subset of this data, comprised of only those points within the forested part of Canada, was selected for study. Fire season length was calculated from data sets of both the 1 × CO2 and 2 × CO2 runs of the model as well as for the actual climate, using observed data from weather stations. A comparison made between the results of the 1 × CO2 and 2 × CO2 runs indicated a significantly longer fire season across the country under a doubling of atmospheric CO2 levels. Implications of this result, such as a fall fire season in Canada's east and greater strains on management agencies, are discussed.
Comparaison entre des prismes de différents facteurs de surface terrière pour établir la structure des diamètres d'un peuplement inéquienne
Authors: Grenier Yvon , Sablon Marc Du
Published: February 2014

A complete forest survey was conducted on an 18-ha unevenaged maple stand to derive its diameter structure. Seventy-two sampling points were also established in the same area using prisms of basal area factor of 2, 3, 4 and 5 m2/ha. Simulation of sampling was performed by varying number and dispersion of points. Two sampling points per hectare with a prism of basal area factor of 2 m2/ha gave the best results in representing this entire stand at a probability level of 90%, with a confidence level of α = 0.05. Sampling units have to be scattered as much as possible in the forest area to be surveyed.
Jack pine establishment in Ontario: 5-year comparison of stock types ± bracke scarification, mounding, and chemical site preparation
Authors: Sutton R. F. , Weldon T. P.
Published: February 2014

Field experimentation was begun in 1984 to assess performance of jack pine (Pinus banksiana Lamb.) (2 + 0 bareroot and FH408 Japanese paperpot) in relation to mechanical site preparation, including Bracke scarification with and without supplementary mounding, and site preparation using Roundup® herbicide. Twenty treatments encompassed 4480 trees in 40-tree plots split equally between bareroot and paperpot stock. The study site, about 200 km north of Sault Ste. Marie, Ontario, had deep silt loam soil. After 3 growing seasons, survival was significantly higher among bareroot than among paperpot stock, but survival no longer differed significantly (P < 0.05) between stock types 2 years later. In years 4 and 5, the rate of increase in mean total height of bareroot stock was 11% less than that of paperpot stock, though bareroot stock was 40 and 4.7 cm greater in mean total 5th-year height and 5th-year height increment, respectively. Paperpot stock needed mechanical site preparation more than did bareroot stock. By the end of year 5, positive responses of survival and growth to mounding had become clear in both stock types; however, although mound size had little or no effect on survival or total height, mean stem volume was significantly (P < 0.01) greater on 20-L vs. 10-L mounds. Fifth-year mean stem volume was also significantly (P < 0.01) greater on mineral-on-organic (M/O) than on mineral-on-mineral (M/M) mounds. Chemical site preparation had no effect on relative growth rates beyond year 3. Indices that combined survival with total height or stem volume after 5 years show the significant (P < 0.01) superiority of: 20-L vs. 10-L mounds, M/O vs. M/M mounds, and chemical vs. no-chemical site preparation.
Establishment of white spruce and black spruce in Boreal Ontario: Effects of chemical site preparation and post-planting weed control
Authors: Wood J. E , Althen F. W. von
Published: February 2014

Five-year results of a field experiment to evaluate the effects of vegetation control either before or after planting on the performance of planted white spruce (Piceaglauca [Moench] Voss) and black spruce (P. mariana [Mill.] B.S.P.) transplants and black spruce containerized seedlings are reported. Annual vegetation control with and without chemical site preparation significantly (P < 0.05) improved height growth, ground-level stem diameter, and health of the planted seedlings. Survival and seedling growth were significantly (P < 0.05) higher with chemical site preparation than with chemical release in August of the year after planting. From the beginning of June to the first half of August, soil temperatures were higher in the plots with no competing vegetation than in the control plots. The difference in temperature reached a maximum of 5 °C at 5 cm of depth and 4 °C at 12 cm of depth. Key words: black spruce, chemical site preparation, glyphosate, growth response, Picea glauca, Picea mariana, release, tending, vegetation management, weed control, white spruce
Prototype energy plantations in Ontario
Authors: Kenney W. A. , Gambles R. L. , Zsuffa L.
Published: February 2014

Biomass production for energy from short rotation forestry plantations can contribute to Ontario and Canada's objectives of reducing CO2 emissions. Technologies aimed at production and conversion of this biomass have progressed considerably, but large scale plantations are needed to obtain reliable figures regarding yields and costs, as well as to provide venues for testing equipment and to demonstrate the technology to growers. A project initiated by the Faculty of Forestry, University of Toronto will establish a number of prototype willow plantations on private land, to meet these needs. The objectives of the project, progress to date and the long-term plans are presented. Key words: SRIC, short rotation forestry, demonstration, willow, energy biomass
Towards making willows pilot species for coppicing production
Authors: Gullberg Urban
Published: February 2014

Long and short term breeding of willows for energy production in Sweden and basic research related to these activities is presented. The strategy is to concentrate on one species, S. viminalis, to functionally separate long and short-term breeding and to emphasize general biological research on Salix. In the long term breeding we have a sub-divided breeding population where we aim for inbreeding in the sublines. The selection of cultivars is based on both family and individual selection and cloning is used in this process. The basic research is concerned with the components of growth, the genetics of small populations and host-parasite interaction. Key words: genetics, long term breeding, S. viminalis, subdivided breeding population, components of growth, small populations, host-parasite interaction.
An overview of non-wood valuation efforts in Ontario
Authors: McKenney D. , Sarker R.
Published: February 2014

The value of various un-priced (non-wood) outputs or services from forests is becoming an increasingly important component of management planning. This paper reviews the methods economists have developed to derive monetary estimates of these values. From a decision-making perspective, the primary goal of such efforts is for comparison of competing values. The paper also reviews all the un-priced valuation studies that have taken place in Ontario. There is considerable scope for additional empirical research on un-priced forest values, not only in Ontario, but elsewhere in Canada. Key words: non-timber values, un-priced valuation, Ontario case studies
Stand density management diagram for managed black spruce stands
Authors: Newton P. F. , Weetman G. F.
Published: February 2014

A stand density management diagram for managed black spruce (Picea mariana (Mill.) B.S.P.) stands was developed using data derived from 37 variable-size temporary and permanent sample plots, and 257 open-grown sample trees. The plots were situated within 15 plantations and 4 precommercially thinned stands located throughout central and western Newfoundland, north-western New Brunswick and northern Ontario. The basic components of the diagram included: (1) an approximate crown closure line (2) the self-thinning rule (3) expected size-density trajectories and (4) isolines for dominant height, relative density index, quadratic mean diameter and merchantability ratio. The utility of the diagram was demonstrated by deriving yields for various initial spacings by site class and subsequently evaluating various outcomes in terms of operability criteria. In addition, the potential of estimating the time of crown closure by initial spacing and site class is discussed in relation to minimizing the adverse effects of Kalmia angustifolia (L.) on black spruce growth and development. Key words: stand density management diagram, initial spacing, black spruce, operability, Kalmia angustifolia (L.)
The impact of fire on timber supply in Ontario
Authors: Martell David L.
Published: February 2014

Results are presented for an assessment of the impact of fire on timber supply in the province of Ontario. Historical fire report data are used to develop statistical summaries of fire regimes in terms of annual fire occurrence and area burned by administrative district and region. A simple hypothetical jack pine forest is used to illustrate how forest level timber harvest scheduling models can be employed to assess the timber supply implications of fire management regimes. Although fire may have had a significant detrimental impact on timber supply in some parts of the Northwestern region during the 1976-88 period, the effectiveness of Ontario's forest fire management system is such that timber supply in most districts has not been significantly diminished by fire. The results of our timber supply analysis, and the fact that fire management also benefits public safety and reduces property loss, suggest forest fire management is profitable in Ontario. Key words: forest fire impact, timber supply, mathematical programming, Ontario
20-year growth of white pine following commercial improvement cut in pine mixedwoods
Authors: Stiell W. M. , Robinson C. F. , Burgess D.
Published: February 2014

Understory 55-year-old white pine (Pinus strobus L.) in mixedwood stands were released in 1971 from an (ca. 80-year-old) overstory of intolerant hardwoods using wheeled skidders in a commercial logging operation. The main aim of the study was to increase the growth and yield of white pine for sawlogs over the following 20 to 30 year period by releasing suppressed pine. Growth of released, healthy white pine was assessed after logging for a range of stand densities (basal areas of 6.9, 11.5, 16.1 m2 ha−1) using suitable control plots and a randomized complete block design with five replicates. Plots were remeasured 10 and 20 years after treatment. By harvesting, much of the natural mortality associated with these stands over the 20-year-period was utilized. Growth responses associated with overstory release were highly significant and demonstrated an 80% increase in sawlog volume increment for treated stands after 20 years. Herb diversity was higher in treated stands and browse potential was not affected. However, white pine regeneration was unacceptably low in all cases. Overstory release increased the natural rate of succession in these stands, but without further management activities or wild-fire, the study area will revert to the economically lower-valued hardwoods. Key words: white pine, growth and yield, mixedwood management, understory release, ecosystem response
Current understanding of white and red pine physiology
Authors: Wetzel Suzanne , Burgess Darwin
Published: February 2014

For significant and predictable improvements in productivity of red and white pine forests, an increased understanding of the physiological processes in these species is essential. Relatively little physiological research has focused on these two species over the last two decades. However, with renewed interest in these species now for their high social, environmental and economic value this situation is changing. This paper describes past efforts at understanding red and white pine physiology, as well as discussing recent achievements. In addition, new results obtained by the authors through the use of Biotronic growth units are described in more detail to emphasize the high adaptability of white pine seedlings in response to nutrient stress through changes in carbon distribution, nutrient uptake and utilization.The ultimate practical output of much forestry research is often models predicting tree and forest growth. However, models which are based solely on empirical growth measurement data will not provide the understanding that is necessary for sustainable management; thus, increased research on physiological processes will continue to be required in future. Long-term detailed field studies that consider environmental and silvicultural influences at the organ and whole tree level are required to ensure that future models have high explanatory value. Key words: white pine, red pine, tree physiology, photosynthesis, seedling nutrition, silviculture
White pine management in the Ottawa River area of Quebec
Authors: Brown Jean-Louis
Published: February 2014

Over the past few years, white pine management in Quebec has moved from diameter-limit cutting and clear cutting to silvicultural treatments that are more concerned with regeneration of these forests and are better adapted to the structure and phytosanitary condition of stands. The goal is to achieve sustained yield in management units by ensuring forest regeneration and maintenance of, or increase in, stem quality in the residual stands through the application of appropriate treatments by wood fiber users. To continue to improve management methods in order to take maximum advantage of the potential of wood production in existing stands, use of the concept of diameter of maturity instead of age of maturity for determining stem and stand maturity is proposed. Key words: Forest management, standards, white pine, diameter of maturity, age of maturity
A Christmas tree market analysis: implications from Alberta, Canada data
Authors: Woodard P. M. , Needham D. , Phillips W. E. , Constantino L. F.
Published: February 2014

The 1990 Christmas tree market in Alberta, Canada was assessed in an attempt to determine the feasibility of growing such trees for local consumption. Almost 5 500 questionnaires were delivered to households and commercial establishments as part of this survey. In addition, many personal interviews were conducted. The information presented pertains to the wholesale and retail sales volumes and values by tree species. The socio-economic background of tree buying consumers and their traditional celebration and purchasing habits are also included. Our results suggest Albertans spent over $7 million (retail) to buy 300,000 natural Christmas trees during the 1990 holiday season, and that 87% of the wholesale value or $2.6 million was spent to buy trees from outside of Alberta. Consumers would prefer to buy high-quality, locally-grown trees.
A general equilibrium analysis of the economic impact of a reduction in harvest levels in British Columbia
Authors: Binkley Clark S. , Percy Michael , Thompson William A. , Vertinsky Ilan B.
Published: February 2014

This paper examines the economic and social consequences of possible reductions in the Annual Allowable Cut (AAC) in the province of British Columbia. Following a review of studies of the role of the forest industry in the economy of British Columbia, a general equilibrium model is presented to examine the economic impact of AAC reduction where prices of forest products are allowed to fluctuate. While the studies reviewed and this study use different methodologies, the conclusion that emerges is robust: the economic impact of AAC reduction is significant and negative. The social costs in terms of unemployment and community stability/survival are even higher. The paper concludes with a set of recommendations intended to ensure that decisions concerning harvesting reflect comprehensively the costs and benefits involved in terms of the timber and non-timber values involved.
Le feu : agent de contrôle des insectes
Authors: Dupuis M. Martin
Published: February 2014

For millenia, fire and insects have played an important role in forested land evolution. Understanding the roles they play can be important in helping us not only to control them, but to use them as an ecological tool. Also, we notice some important interactions between these two agents. As insects affect fire, fire may control insect pests. Controlled burning may provide excellent results, but allows a very slight margin for possible errors. Fire use as an insect mangement tool, requires a very precise and wide knowledge of weather conditions, fire intensity, insect's life cycle, available fuels, and type of ecosystem involved.After a long run of experiences and research, we notice that fire has been and will always be an important factor in equilibrium of some ecosystems. Since wild fire prevention campaigns and the emergence of insecticides, some forests have become excessively vulnerable to insect pests. Proper knowledge, and use of fire control, rather than immediate suppression of forest fires, would allow us to conserve various ecosystems in a healthy balance.
Trends in forest management in the United States
Authors: Thomas Jack Ward
Published: February 2014

Changes in forestry practices in the United States have been dramatic over the past decade. These changes have been brought about largely through government regulations promulgated in response to pressure from environmental and other groups at both federal and state levels. Historically, the federal government has taken leadership in forest stewardship, though some states have demonstrated strong initiatives over the years. Two separate, but intertwined, factors combined to alter the practice of forestry over much of the United States. There were the interactive consequences of obedience to national environmental laws, passed in the 1960s and 1970s, and a rising environmental consciousness among the majority of the minority of the citizenry who care about natural resource issues. Rising public concern was focussed in challenges in the federal courts to government forest management activities, and in terms of public relations campaigns using lobbying, demonstrations, and manipulation of the mass media. In July of 1993, President Clinton selected an option for management of federal forests in the Pacific Northwest section of the United States that dedicated 9.28 million acres (3.75 million hectares) of federal forests to reserves to be managed for late-successional/old-growth ecosystem function and riparian/fisheries protection. This reduced the anticipated timber sale levels from the 2.4 billion board feet (5.7 million m3) cut annually in 1990-1992, to 1.2 billion board feet (2.8 million m3) projected for 1994. There is an ongoing shift in management philosophy toward "ecosystem management" of forested lands with increasing attention to aesthetics and more benign environmental effects of timber management.
The Zimbabwe Natural Resources Management Programme and lessons in cross-cultural exchange
Authors: Milne G. R. , Hoole A.
Published: February 2014

Since early 1992, the Ontario Ministry of Natural Resources has been executing a five year, $19 million CIDA-funded capacity building programme in the Republic of Zimbabwe, in southern Africa. The programme has a policy development project (EPCU) in the Ministry of Environment and Tourism head office, and an operational level project (RTB) in the Department of Natural Resources. Training and the exchange of skills, knowledge, and experience are critical elements in both projects. The cross-cultural exchange method used by the two Canadian EPCU advisors has evolved from a direct one-on-one approach with only two Zimbabwean counterparts, to a broader approach involving five primary counterparts in the immediate unit, and several secondary counterparts in other branches of the local Ministry. Both approaches have advantages and disadvantages. From experience gained to date however, the broader approach appears better suited for implementing the EPCU project objectives in light of local conditions and constraints.
Forest neighbourhoods for timber harvest scheduling
Authors: Wightman Rick A. , Baskent Emin Z.
Published: February 2014

Forest management involves exploring through time the scheduling opportunities for timber and non-timber values within a forest. The ability to identify and form neighbourhoods — areas of suitable stand conditions and locations — is critical to this endeavour. This paper presents a GIS-based algorithm for identifying and forming forest neighbourhoods suitable for timber harvest scheduling. The resulting neighbourhoods are contiguous and overlapping, composed of stands sharing similar attributes. Similarity is based on a definable similarity list where stand conditions closest to one another in the list are most similar to one another. The algorithm is demonstrated with a single stand example and then a small forest example. Control of neighbourhood size is limited using a vector data model, except in forests composed of small stands. The examples illustrate that neighbourhood inclusion is dependent on both a forest stand's condition and relative position in the forest. The paper concludes with suggestions for further development of the algorithm. Key words: timber harvest scheduling, forest management, spatial modelling, GIS, neighbourhoods
Growth and form responses to pre-commercial thinning regimes in aerially seeded jack pine stands: 5th year results
Authors: Morris D. M. , Hills S. C. , Bowling C.
Published: February 2014

In 1986, a thinning trial was established in a 9-year-old jack pine stand near Dryden, Ontario. Four blocks consisting of five thinning regimes (1 m × 1 m, 1.5 m × 1.5 m, 2 m × 2 m, 2.5 m × 2.5 m, 3 m × 3 m) and a control plot were established using a randomized complete block design. Once thinned, a series of measurements were taken in 1986 and repeated in 1991 to determine growth and form responses. Results identified highly significant responses for DBH growth and individual stem volume growth. Height response did not vary among the spacing levels. Changes in crown dimensions and stem taper were used to evaluate form responses to thinning. A highly significant decline in all form variables was found in response to increased spacing. Although the increased growth in individual trees provides an opportunity to produce a wider array of products, it appears to be at a cost of reduced form characteristics. Specific management implications for the Dryden Crown Forest are discussed. Key words: jack pine, pre-commercial thinning, growth and form responses
Distribution and occurrence of western gall rust in thinned jack pine stands
Authors: Hills S. C. , Morris D. M. , Bowling C.
Published: February 2014

Jack pine (Pinus banksiana Lamb.) is one of the most important commercial species in northwestern Ontario and is the principal host of one of the most serious stem rusts, western gall rust (WGR) caused by Endocronartium harknessii (J.P. Moore) Y. Hirat. In 1986 a trial was established to determine, in part, effects of precommercial thinning on the distribution and occurrence of WGR in jack pine. A 9 year-old aerially seeded jack pine stand was thinned to square spacings of 1 m, 1.5 m, 2 m, 2.5 m, 3 m and a control. Fifth-year results indicated that a significant quadratic trend (p = 0.014) existed between spacing and stem gall infection rate. The incidence of WGR (stem galls) increased as stand density decreased to a maximum at 1.5 m spacing, and then declined to roughly the infection rate of the control at the lowest density (3 m). A significant relationship (0.084) between crown class and the rate of branch gall infection rate was also detected. The branch gall infection rate decreased from 6.2% year−1for dominant trees to 2.8% year−1for trees categorized as suppressed. Based on these results, pre-commercial thinning operations should target those trees with main stem galls and/or numerous branch galls, regardless of size and crown position, and then focus on the removal of suppressed trees to meet the desired density target. This strategy should not only enhance growth of the remaining trees, but also reduce WGR inoculum levels and reduce future WGR-related mortality. Key words: jack pine (Pinus banksiana Lamb.), western gall rust (Endocronartium harknessii (J.R Moore) Y. Hirat.), pre-commercial thinning, white pine weevil (Pissodes strobi Peck.)
Economics of protecting wilderness areas and old-growth timber in British Columbia
Authors: van Kooten G. Cornelis
Published: February 2014

This study examines the costs and benefits of preserving old-growth forests in British Columbia. Estimates of the present worth of old growth in timber production are compared with the measurable non-timber benefits from preserving old-growth, with the differences between the commercial timber and measurable non-timber values attributed to the unmeasured components of non-timber values. Economic efficiency benefits are then compared with benefits that accrue in other accounts used to analyze decisions. For reasonable values of non-timber values, current levels of wilderness protection (and thus of old growth) are more than adequate on the Coast, but an increase in wilderness area of 1.6 million ha (or some 80,000 ha of old growth) might be economically justifiable. Key words: economics and preservation of wilderness, protection of old growth, multiple accounts analysis
The white pine weevil in British Columbia: Basis for an integrated pest management system
Authors: Alfaro Rene I. , Borden J. H. , Fraser R. G. , Yanchuk A.
Published: February 2014

Research programs to date in British Columbia on the biology, damage and control of the white pine weevil, Pissodes strobi (Peck), a pest of spruce, Picea spp. and pine, Pinus spp., are reviewed. Significant progress has been made in the areas of genetic resistance, silvicultural and chemical control. An integrated pest management (IPM) system is formulated which combines silviculture-driven and resistance-driven tactics. The system relies on accurate hazard rating of plantation sites and requires continuous monitoring of attack levels and the forecasting of plantation productivity under various IPM tactics through the use of a decision support system. Research needs which would increase effectiveness of the IPM system are reviewed and organized in the context of the plantation productivity cycle. Key words: insect control, Pissodes strobi, IPM, genetic resistance, silvicultural control, chemical control, decision support system
Comparison of relative accuracy and time requirement between the caliper, the diameter tape and an electronic tree measuring fork
Authors: Binot Jean-Marie , Pothier David , Lebel Jeannot
Published: February 2014

This study compares the relative accuracy of diameters measured with the caliper, the diameter tape, and the electronic tree measuring fork (ETMF) Tally BoyMC with and without reflector. The time required for the measure and the data entry of diameters to computer for each instrument was also evaluated. Significant differences in mean DBH (diameter outside bark at breast height — 1.3 m above ground) generally occurred among instruments. Nevertheless, even if these differences were significant, they were less than 1 cm for five of the six species tested. For white pine (Pinus strobus L.), however, the use of the ETMF without reflector led to an important overestimation of the DBH in comparison to the caliper, the diameter tape and the ETMF with reflector. The typical fissured bark observed on white pines could probably explain that overestimation. For all species, the addition of the reflector to the ETMF decreased the differences among instruments. The measures taken with the diameter tape were slightly larger than those made with the caliper. In comparison to the diameter tape and the caliper, the ETMF reduced the time required for date collection from 35 to 45%. Key words: diameter measurement, timber inventory
Short-term Performance of two hexazinone formulations: Efficacy, seedling survival and growth
Authors: Reynolds Phillip E. , Roden Michael J.
Published: February 2014

Liquid (VELPAR L) and dry-flowable (VELPAR ULW) hexazinone (2 kg ai ha−1) were aerially applied to a northern New Brunswick clearcut to reduce raspberry [Rubus idaeus L. var. strigosus (Michx.) Maxim] competition. Treatments were applied in June 1987; planting with containerized (multipot) black spruce [Picea mariana (Mill.) B.S.P.] was conducted 2 and 14 months after treatment in August 1987 and 1988. Seedling survival and growth were measured yearly through August 1991. Hexazinone formulation did not affect raspberry control, seedling survival, or growth. Five growing seasons after treatment, raspberry cover was generally less in treated plots than in controls. Seedling survival did not differ among treatments for seedlings planted at either time interval after hexazinone treatment. Seedlings planted 14 months after hexazinone treatment grew poorly compared with those planted 2 months after herbicide treatment. Stem volume of seedlings planted 2 months after hexazinone treatment exceeded that of control seedlings in the first growing season after planting and remained greater than that of control seedlings through 1991. Stem volume increases over controls were restricted to the second growing season after planting for seedlings planted 14 months after hexazinone treatment. Fourth-year stem volume of seedlings planted 2 months after hexazinone treatment was correlated with raspberry cover (r2 = 0.34). As raspberry cover increased, black spruce growth decreased. Key words: liquid hexazinone, dry-flowable hexazinone, site preparation, black spruce, multipot stock, seedling survival, stem volume, raspberry cover
Hexazinone site preparation improves black spruce seedling survival and growth
Authors: Roden Michael J. , Reynolds Phillip E.
Published: February 2014

Granular (PRONONE 10G and 5G) and liquid (VELPAR L) hexazinone (1 to 4 kg ai ha−1) were applied to a northern New Brunswick clearcut (loams, silt loams, and clay loams) to reduce raspberry [Rubus idaeus L. var. strigosus (Michx.) Maxim] competition. Treatment, using skidder-mounted herbicide application equipment, was completed in May and September 1986, with planting of 2+2, bareroot, black spruce seedlings [Picea mariana (Mill.) B.S.P.] in June 1986 and in June 1987. Seedling survival and growth were measured yearly for five growing seasons after planting. By August 1991, raspberry cover for three treatments remained less than that for controls. Survival of seedlings planted approximately one month after spring treatment was less than controls, but seedling height and stem diameter were greater than that of control seedlings for most treatments. Survival and growth of seedlings planted approximately one year after spring treatment or nine months after fall treatment were greater than that of control seedlings for most treatments. Fifth-year height and stem diameter of seedlings planted nine months after fall treatment were negatively correlated with raspberry height (r2 = 0.729, height and 0.745, diameter), decreasing as raspberry height increased. Over the five-year observation period, hexazinone formulation did not affect raspberry control, but did affect seedling survival and growth. Spring treatment with PRONONE 10G (2 kg ai ha−1), with planting delayed by one year, provided the best treatment to achieve both optimal seedling survival and growth during plantation establishment. Key words: liquid hexazinone, granular hexazinone, site preparation, black spruce, growth parameters, seedling survival, raspberry competition
Évaluation de trois contenants pour la production de plants d'espèces feuillues de fortes dimensions
Authors: Cogliastro Alain , Hallé Andrée , Labrecque Michel , Daigle Stéphane
Published: February 2014

Three types of containers of different volumes (Polymos 15, 700 cm3; Polymos 12, 1,000 cm3; Whitcomb®, 3,500 cm3) were tested to produce large hardwood seedlings. Studies of growth and root development of three species, white ash (Fraxinus americana L.), bur oak (Quercus macrocarpa Michx.) and northern red oak (Quercus rubra L.) were used to assess containers after two growing seasons in an unheated plastic shelter. The mean height of seedlings increased with the volume of the containers. The total dry mass of seedlings at 55 cm in height was more important in the larger container; the total root mass and the proportion of secondary roots were higher in the container of greater volume. For the two species of oak, the 3,500 cm3 container produced seedlings with a taproot showing a number of deviations when touching the bottom of the container. White ash, a species with a fibrous root system, showed a higher deviation index in the smaller containers. The openings on the sides of the square-shaped Whitcomb® containers were effective for the air-pruning of secondary lateral roots of species with a taproot and their volume allowed for an important root mass. However, the flat bottom with openings at each of the four corners did not prevent deviation of the primary root. The use of a bottomless square-shaped container with a volume greater than 1,000 cm3 and with adequate lateral openings would optimize the production of large seedlings of hardwood species with taproot. Key words: large containerized seedlings, root development, root deviation, Quercus sp., Fraxinus sp.
Utilization and management of forest resources in Zaire
Authors: Khasa P. D. , Bousquet J. , Vallée G. , Bélanger J.
Published: February 2014

Tropical forest biomes are characterized by a high biodiversity. However, this biological complexity is diminishing rapidly. The causes for the decline and deterioration of tropical forests in Zaire were analysed. The main factors causing loss of biodiversity are shifting agriculture, fuelwood consumption, and fires in open forests and savannas. Measures for maintenance of forest biodiversity are proposed. These include in situ and ex situ conservation, suitable agricultural and silvicultural management systems, based on knowledge of genetic structure, genecology, reproductive biology of tropical plant populations, and biotic and edaphoclimatic factors. The active participation and support of the Zairean people as a whole, and policy and institutional reform are essential for a more effective utilization, management, and protection of the forests, so that socio-economic and environmental benefits are provided for present and future generations. Sustainable forestry development requires also a greater collaboration between government agencies and local communities and non-governmental organizations (NGOs). Key words: Biodiversity, deforestation, national tropical forestry action plan, sustainable development, tropical forests, Zaire
ARNEWS assesses the health of Canada's forests
Authors: Hall J. Peter
Published: February 2014

In 1984 the Canadian Forest Service (CFS) established the Acid Rain National Early Warning System (ARNEWS) to monitor the state of health of Canada's forests. This program was implemented by the CFS Forest Insect and Disease Survey (FIDS) who survey the plots annually and determine the causes of observed damage. For the period, 1984-1994, the survey indicates that there has been no large-scale decline in the health of Canada's forests. Insects, diseases and abiotic conditions have impacted forests, and isolated cases of damage caused by air pollution have been observed. The presence of unknown damage is also being investigated to determine if pollution is involved. The results of this survey support the need for a national forest health monitoring network as part of sustainable management of Canadian forests. Key words: forest health, forest surveys, sustainable forestry, ecosystem monitoring
Effets du brûlage dirigé et du scarifiage sur l'établissement des semis et sur leur interaction avec la végétation concurrente
Authors: Tellier Renée , Duchesne Luc C. , McAlpine Robert S. , Ruel Jean-Claude
Published: February 2014

In 1990, a jack pine forest was clear-cut on an 15 ha area and divided into 40 plots. In 1991, ten plots were burned-over under varying conditions to obtain different fire intensities and ten plots were scarified. Each plot was planted in 1992 with red pine (Pinus resinosa Ait.) and white pine (P. strobus L.) seedlings. Survival rate and health of the seedlings was evaluated for the first two years after planting and the non-crop vegetation was assessed using a competition index developed for conifer management in Ontario. Our results show seedling survival rate, health, biomass and height to be improved when planted on burned-over or scarified sites and that fire intensity influences certain of those characteristics. Key words: scarification, fire, Pinus resinosa, Pinus strobus, competition
Aspen improvement strategies for western Canada — Alberta and Saskatchewan
Authors: Li Bailian
Published: February 2014

A breeding plan was developed for improving trembling aspen (Populus tremuloides) and aspen hybrids for fiber and wood production in Alberta and Saskatchewan. Phenotypic selections are being made from three major geographic regions, northern Alberta (55°-57° N, 114°-120° W), southern Alberta (53°-55° N 114°-120° W), and East-central Alberta and western Saskatchewan (54°-56° N, 107°-114° W). The initial breeding population will include 150 phenotypically selected individuals, 50 from each of the three regions. Open-pollinated seed will be collected and a provenance study will be established to examine the genetic variation in growth and adaptability across the regions. A simple recurrent breeding program for general combining ability will be implemented to improve pure trembling aspen. Initial breeding will be done within each of the three geographic regions until provenance information is available. A nested polycross mating design will be implemented to evaluate the selected parents and generate new breeding materials. Based on early measurements in progeny tests, outstanding parents will be selected to produce planting stock for operational planting. Selections for second generation breeding will be made at age 10 after wood quality and disease resistance can be evaluated reliably. A combined family- and within-family selection will be used to form a new breeding population. The initial focus of the hybrid breeding program will be to identify the interspecfic aspen hybrids that are suitable for planting in northern latitudes. Hybridization will concentrate on crosses between the local trembling aspen and northern sources of P. tremula and P. davidiana. Key words: aspen selection, breeding, hybridization, P. tremuloides, P. tremula and P. davidiana