Moose Browsing Tends Spruce Plantations More Efficiently Than a Single Mechanical Release

Forest vegetation management can improve planted seedling survival and growth and is thus widely used in plantation silviculture. In some jurisdictions, mechanical release using brushsaws has replaced the traditional use of chemical herbicides for forest vegetation management purposes. However, its associated costs and the increasing difficulty of finding qualified labor represent a challenge. The browsing of competition by large herbivores may represent an alternative to mechanical release when planted seedlings are resistant to browsing. Here, we compare the efficacy of moose browsing relative to mechanical release in controlling competing vegetation and in promoting white spruce growth in plantations. In a high moose density region, we used an experimental design consisting of four pairs of moose exclosures and unfenced plots; fifty percent of both the access-restricted and unrestricted study areas received a mechanical release treatment. Moose browsing was more efficient than mechanical release in diminishing the sapling density and basal area of competing species. Mechanical release only reduced the sapling density of taller competitors (height > 201 cm), whereas browsing reduced the sapling densities of competitors across a greater size range (height > 130 cm). These effects of moose browsing on competition translated into a greater positive effect of moose browsing on the basal area of planted spruces. We attribute the higher effectiveness of moose browsing relative to mechanical release to its chronic nature. Moose browsed continuously throughout the year and for multiple years, whereas mechanical release was applied only one time between the second and fourth years after planting. Our results suggest that pairing wildlife management and silviculture decisions could be in the best interest of both the hunting and forestry industries in regions where plantations are frequent and use browse-resistant crop trees. Favouring browsers in controlling the density of competing species could increase the hunting experience and income, while providing an effective, cost-free, and socially acceptable forest vegetation management service.

Interactive Effects of Stock Type and Forest Vegetation Management Treatments on Douglas-Fir Seedling Growth and Survival—Ten-Year Results

In the Pacific Northwest, the use of forest vegetation management (FVM) and seedling stock type selection are important tools to ensure seedling establishment according to organizational objectives and state laws. Individually, these two reforestation decisions have been shown to increase growth and survival of Douglas-fir seedlings, however, the interaction between seedling stock type and level of vegetation control represents economic and ecologic tradeoffs that are less well understood. This study was designed to test the combined effects of three FVM regimes and three containerized stock types, one of which was experimental at the time, on Douglas-fir growth during the initial ten years of establishment on a site near Belfair, Washington (USA). When compared to the no-action control, FVM treatments reduced competitive plant cover below 20% during the year of application, and differences in vegetation cover persisted through the fifth growing season. Vegetation species diversity recovered quickly after FVM and there were no differences among the treatments by the third growing season. After ten growing seasons, trees in plots treated with FVM were 1.1 m taller with a mean diameter at breast height (DBH) 2.2 cm larger than those in the no-action control. Larger seedlings at the time of planting (styro-60) were 0.6 m taller with a mean DBH 1.1 cm larger than smaller seedlings (styro-8 and styro-15). The only significant stock type by FVM interaction in the experiment occurred with the survival of styro-60 seedlings growing in the no action control which had lower survival than all other treatment combinations (67% vs 91%). The long-term competitive impact of shrub cover was demonstrated by a strong non-linear relationship. Increasing cumulative shrub cover from 10% to 30% during the first two years of establishment reduced stand volume at year 10 by 79%.

The use of forests in the river Zagrza basin for the conservation of its hydrological and water protective function

The data on forests shown in this paper which are general useful functions determine the main way of managing, because these forests are marked as water protective and especially significant for the water supply of the Vrnjacka Banja area from 1985. These are forests of beech and beech mixed with fir of the highest quality located in the river Zagrza basin on mountain Goc and they represent more than 85 % of the basin and provide the hydrological and water protective functions at the highest level. For that reason, they have a special protective status. In the river Zagrza basin, there is the management unit "Seliste" of particular importance and the accumulation Seliste was built there with about 380 000 m3 volume and its primary task is water supply of the Vrnjacka Banja area during critical months without water. The aim of this scientific paper is to emphasize the need of increasing and protecting the water potential using adequate ways of forest vegetation management, which means overall basin organization. The final result should be related to the optimal use of natural sources in that area.

Yield Responses of Black Spruce to Forest Vegetation Management Treatments: Initial Responses and Rotational Projections

The objectives of this study were to (1) quantitatively summarize the early yield responses of black spruce (Picea mariana(Mill.) B.S.P.) to forest vegetation management (FVM) treatments through a meta-analytical review of the scientific literature, and (2) given (1), estimate the rotational consequences of these responses through model simulation. Based on a fixed-effects meta-analytic approach using 44 treated-control yield pairs derived from 12 experiments situated throughout the Great Lakes—St. Lawrence and Canadian Boreal Forest Regions, the resultant mean effect size (response ratio) and associated 95% confidence interval for basal diameter, total height, stem volume, and survival responses, were respectively: 54.7% (95% confidence limits (lower/upper): 34.8/77.6), 27.3% (15.7/40.0), 198.7% (70.3/423.5), and 2.9% (−5.5/11.8). The results also indicated that early and repeated treatments will yield the largest gains in terms of mean tree size and survival. Rotational simulations indicated that FVM treatments resulted in gains in stand-level operability (e.g., reductions of 9 and 5 yr for plantations established on poor-medium and good-excellent site qualities, resp.). The challenge of maintaining coniferous forest cover on recently disturbed sites, attaining statutory-defined free-to-grow status, and ensuring long-term productivity, suggest that FVM will continue to be an essential silvicultural treatment option when managing black spruce plantations.

What are the Environmental Consequences of Using Silviculturally Effective Forest Vegetation Management Treatments?

In this paper, we present examples of stand-level consequences of using forest vegetation management treatments in boreal and temperate forest ecosystems in Canada. Specifically, we address several selected indicators: air and water quality, soils and nutrients, plant diversity, and wildlife habitat. For each of these, we discuss direct and indirect effects of five broad categories of treatments: (1) silviculture and harvesting systems and (2) physical, (3) thermal, (4) cultural, and (5) chemical/biological treatments. Our emphasis is on forest vegetation management treatments that are currently used in Canada to manage conifers. By applying regulations and best management practices, conducting landscape-level analyses and developing longer-term monitoring programs resource managers can minimize the effects of FVM treatments on the environmental indicators presented in this paper.

Synthesis of Silviculture Options, Costs, and Consequences of Alternative Vegetation Management Practices Relevant to Boreal and Temperate Conifer Forests: Introduction

In 2007, a multi-agency, multi-disciplinary team from across Canada embarked on an exercise to synthesize knowledge about forest vegetation management alternatives and their use in northern forests. This exercise involved: (1) updating the Canadian Forest Pest Management database, (2) synthesizing relevant forest vegetation management literature, (3) conducting stand-level wildlife, wood quality, yield, and benefit–cost analyses, (4) conducting landscape-level analyses to determine the effects of a systematic reduction in herbicide use on forest management objectives, and (5) transferring the relevant information to forest managers. The results are presented as ten papers in this special issue of The Forestry Chronicle.

Social Concerns, Risk and The Acceptability of Forest Vegetation Management Alternatives: Insights for Managers

Although public opinion and social issues have significant influence on policy-making, research on forest vegetation management (FVM) in Canada has a strong focus on biological aspects, with less attention being paid to social concerns. This paper reviews the social context in which FVM occurs. Individual views about FVM reflect a combination of values, beliefs, and attitude while also including differing perceptions of risks. Public views and the broader social acceptability of management decisions can be linked to five key factors: context, risk, aesthetics, trust, and knowledge. Judgements about acceptability will usually change over time and across specific situations and various segments of a population could make opposing judgements. We identify a variety of public concerns related to FVM in Canada, synthesizing research that can help resource managers consider the social impacts of their choices. We also note particular concerns related to Aboriginal peoples and the FVM workforce. Information about the benefits and disadvantages of FVM options can help resolve public concerns, but using technical information to convince the public is rarely successful. Forest management agencies and resource managers need access to reliable information about social values and concerns to make management decisions that will be socially acceptable.