Forestry Conditions Research Articles

Performance, Capability and Costs of Small-Scale Cable Yarding Technology

The authors tested two mini-yarders, one for uphill and the other for downhill extraction. The two machines were modern commercial models, offering state-of-the-art yarding technology on a miniature scale and at a much lower cost than required for purchasing a full-size tower yarder. The two units must not be regarded as alternative, but rather as complementary, since they offer different capabilities and advantages. Both machines were tested while harvesting firewood from the thinning of young beech stands in Central Italy. The tests indicated that both units can reach a productivity between 1.5 and 2.4 m3 SMH−1, including all delays, as well as set-up and dismantle time. Calculated extraction cost ranged between 24 and over 30€ m−3. The authors calculated a set of regression equations for estimating machine productivity as a function of the main work conditions. The performance of the studied mini-yarders does not seem much inferior to that achieved by professional light tower yarder under the same work conditions, but the lighter construction of the small-scale units may result in a lower resistance to wear and abuse. In any case, mini-yarders seem ideal for deployment under the typical conditions of small-scale forestry, offering a good solution to wood extraction on steep terrain, competitive with animal and winch logging in terms of productivity, cost and operator comfort.

Vermarktung von Waldleistungen: Engagement, Fachwissen und Solidarität sind gefragt! (Essay) | Commercialization of forest services: active involvement, knowledge of the subject and solidarity are required (essay)

A structure of small surfaces with a large proportion of private forest owners and important stocks of wood characterize forestry conditions in canton Appenzell Outer Rhodes. The forest owners are often lacking in initiative, in specific knowledge, in personal and financial resources and in suitable structures for a successful commercialization of non-wood services. A few positive examples show ways to improve this situation and demonstrate the importance, particularly in the privately owned forest sector, of an actively involved, versatile and interested forest ranger. Increasing the awareness of the various people concerned and their mobilization is of far greater importance than the issuing of new regulations. The forest ranger can help through well-directed encouragement concerning marketing and by an integration of the forest non-wood services into the general forestry development program. One of the aims of the forest policy of the canton is that in the future services provided by the forest which are central matters of concern to the community and the greater running costs associated with these should be appropriately compensated.

Biomass functions applicable to oak trees grown in Central-European forestry

This study describes the parameterization of biomass functions applicable to oak (<I>Quercus robur, Quercus petraea</I>) trees grown in the conditions of Central-European forestry. It is based on destructive measurements of 51 grown trees sampled from 6 sites in different regions of the Czech Republic important for oak forest management. The samples covered trees of breast height diameter (<I>D</I>) ranging from 6 to 59 cm, tree height (<I>H</I>) from 6 to 32 m and age between 12 and 152 years. The parameterization was performed for total aboveground biomass and its individual components. The two basic levels of biomass functions utilized <I>D</I> either as a single independent variable or in combination with <I>H</I>. The functions of the third level represented the best function for each biomass component with the optimal combination of available independent variables, which included <I>D, H</I>, crown length (<I>CL</I>), crown width (<I>CW</I>), crown ratio (<I>CR = CL/H</I>), tree age and site altitude. <I>D</I> was found to be a particularly strong predictor for total tree aboveground biomass. <I>H</I> was found to always improve the fit, particularly for the individual components of aboveground biomass. The contribution of <I>CW</I> was minor, but significant for all biomass components, whereas <I>CL</I> and <I>CR</I> were found useful for the components of stem and living branches, respectively. Finally, the remaining variables tree age and altitude were each justified only for one component function, namely living branch biomass and stem bark, respectively. The study also compares the fitted functions with other available references applicable to oak trees.

Above- and belowground biomass measurements in an unthinned stand of Sitka spruce (Picea sitchensis (Bong) Carr.)

Reporting carbon (C) stocks in tree biomass (above- and belowground) to the United Nations Framework Convention on Climate Change (UNFCCC) should be transparent and verifiable. The development of nationally specific data is considered ‘good practice’ to assist in meeting these reporting requirements. From this study, biomass functions were developed for estimating above- and belowground C stock in a 19-year-old stand of Sitka spruce (Picea sitchensis (Bong) Carr.). Our estimates were then tested against current default values used for reporting in Ireland and literature equations. Ten trees were destructively sampled to develop aboveground and tree component biomass equations. The roots were excavated and a root:shoot (R) ratio developed to estimate belowground biomass. Application of the total aboveground biomass function yielded a C stock estimate for the stand of 74 tonnes C ha−1, with an uncertainty of 7%. The R ratio was determined to be 0.23, with an uncertainty of 10%. The C stock estimate of the belowground biomass component was then calculated to be 17 tonnes C ha−1, with an uncertainty of 12%. The equivalent C stock estimate from the biomass expansion factor (BEF) method, applying Ireland’s currently reported default values for BEF (inclusive of belowground biomass), wood density and C concentration and methods for estimating volume, was found to be 60 tonnes C ha−1, with an uncertainty of 26%. We found that volume tables, currently used for determining merchantable timber volume in Irish forestry conditions, underestimated volume since they did not extend to the yield of the forest under investigation. Mean stock values for belowground biomass compared well with that generated using published models.

Ecological indicators: Imperative to sustainable forest management

Abstract Sustainable forest management (SFM) deals with ecologically sound practices that maintain the forest ecosystem integrity, productivity, resilience and biodiversity. Ecological sustainability ensures continuing function of ecosystems which are considered as ecological life support system. Several attempts have been made world over to develop criteria and indicators, which are specific to various forestry conditions and recognized as appropriate tools for assessing and monitoring progress towards sustainable forest management. In India, the process for measuring forest sustainability has started by evolving national level set of Criteria and indicators in the form of Bhopal–India process. The Bhopal–India process specifies 8 criteria and 43 indicators. The first 4 criteria pertain exclusively to ecology with 21 related indicators. Thus, nearly half of the criteria and indicators pertain to ecological dimensions that largely govern sustainability of forests. Rest of the criteria of the base set pertains to economic and social aspects with related indicators. This provides holistic approach of monitoring the forest resources.

Germany–Agriculture and Forestry

[MWS 6.2 (2006) 207-218] ISSN 1470-8078 Germany—Agriculture and Forestry Max Weber At the last German Census of trades and callings (1895) the number of persons engaged chiefly in agriculture and forestry was 8,300,000, or about 37V2 per cent of the total productive population. This is about the same percentage shown by the U.S. census of 1900, which was 35.9 per cent; but this latter figure would be increased by the large number of land labourers counted simply as laborers. At the same census of 1895 the number of individual agricultural under takings was 5,500,000, with an area of 43,200,000 hectares (1 hectare = IVi acres). Of this total 'agricultural' area 7,600,000 hectares are woods, to which must be added 6,100,000 hectares of timber-land devoted purely to forestry. The greater part of the forests, about 7,000,000 hectares, is in the possession of the German states, espe cially Prussia and Bavaria, and of the local parishes and munici palities; though many forests are owned by large landed proprietors and by private foundations and associations. In strong contrast to the primitive forestry conditions that prevail in the United States, German forests, usually even those owned privately, are nurtured with all the care that the highly developed technic of forestry has made possible, the period of cultivation not seldom being 100 years. In this way 11,000,000 hectares were devoted to the cultivation of high timber, i.e., 2,600,000 hectares to leaf-bearing trees, 8,400,000 hectares to pines and firs. The yield of lumber in 1900 was 20,000,000, of firewood, 18,000,000, of stumps and brushwood, 10,500,000 cubic meters, besides the byproducts, especially tan-bark. Yet this yield does not supply the demand for wood in Germany. In 1904 lumber and building timber were imported to the extent of $20,000,000. Division of land and kinds of production Of the total agricultural area in 1904, 26 per cent was woodland, 49 per cent arable land, including gardens and vineyards, 11 per cent© Max Weber Studies 2006, Department of Applied Social Sciences, London Metropolitan University, Old Castle Street, London El 7NT, UK. 208 Max Weber Studies meadows, and five per cent pasture-land. Of the arable land, 61 per cent was planted with grain and leguminous crops, 17Vi per cent with chopped crops, especially with potatoes and sugar-beets, 10 per cent with forage, 2.6 per cent with fruit and garden vegetables, and 8.7 per cent remained fallow. As regards grain, the dependence of Germany on foreign imports has not increased essentially in recent years. At times it has even decreased. On an average the yearly imports of grain exceed the exports by 2,000,000,000 kilograms, worth $125,000,000; i.e., as to value, about 1-6 or 1-7 of the German yield, or, as to quan tity, about 1-5. In live stock, Germany imports horses, oxen, and cows for $45,000,000; also hogs, but to a limited extent, owing to the restrictive hygienic (in reality protective) measures; further, hides and guts. On account of the ever-increasing intensity in the cultiva tion of the soil, the number of sheep in Germany has decreased from 28,000,000 in 1860 to 9,700,000 at present (U.S. 62,000,000). On the other hand, from 1873 to 1900 the number of horses increased from 3,300,000 to 4,200,000 (U.S. 16,000,000), the number of cattle from 15,700,000 to 19,000,000 (U.S. 61,400,000), and the number of hogs from 7,000,000 to 17,000,000 (U.S. 48,600,000). In 1900 for every 100 inhabitants there were 7.5 horses (U.S. 22), 33.6 head of cattle (U.S. 81), and 30 hogs (U.S. 82). From the high and increasing prices of land alone one could infer that in Germany there has been a consid erably greater increase in weight and quantity, than in quality. In 1900 the sale-value of horses was...

The Effect of Calibration on the Accuracy of Harvester Measurements

Almost all timber in Ireland is harvested using mechanical harvesting heads. All new harvesters come equipped with computerized measurement systems. The objective of the research reported in this article was to assess the impact of calibration on the accuracy of harvester head measurement systems in Irish forestry conditions. The research was carried out on a site in Co. Cork. The harvester was a Timberjack 1270D with a 762C harvester head and the Timbermatic 300 control and measurement system. The harvester measurement system was assessed on its accuracy in measuring the length and volume of individual stems and logs in 9 check runs of 7 or 8 stems. The harvester head measurements were compared to values obtained by caliper-and-tape measurements. The main point that can be taken from this research is that regular calibration will greatly improve the accuracy of the harvester measurement system. After calibration, length measurement by the harvester measurement system of individual logs was very accurate, while volume measurement was unsatisfactory for the pulp log assortment. The differences between the harvester measurements and the caliper-and-tape measurements fluctuated greatly, varying from positive to negative differences within a check run, even after calibration. These fluctuations could indicate an inherent problem associated with the design of the calibration procedure, as the positive and negative differences cancel each other out and the calibration, based on mean values, appears to indicate accurate measurements. More work needs to be done on reducing to impact of the roughness and branchiness of smaller dimension logs on the accuracy of diameter and length measurements in Irish conditions.

Measuring the mobility parameters of forwarders using GPS and CAN bus techniques

Use of a datalogger connected to the CAN bus of an 8-wheeled forwarder’s hydrostatic transmission permits measurement of the gross power on the driveline and the rotational velocity of the drive axle. The ground velocity and trajectory of the forwarder is monitored by the GPS technique. These data allow the total resistance force and wheel slip to be determined under different terrain conditions. In this paper the total resistance force is segregated into rolling, slope and winding resistances. The measuring system was tested in practice on an even tarmac surface and a gently sloping hard earth road, the number of input variables in the first tests having been reduced. It was found that the measuring accuracy permitted detection of about a half percent variation in slope inclination in the test lane. Tests on a figure of 8 track showed that the winding resistance can also be detected. It was concluded that the measuring technique is accurate enough for terramechanical research and practicable under real forestry conditions.

On Sustainable Development of Social Forestry in Bangladesh: Experiences from Sal (Shorea Robusta) Forests

Sustainability in forestry is a complex amalgam of trade-offs among its various dimensions and there is no easy route to achieve sustainable development. It is important that policy process and implementation strategy of these policies should be based on sound information about these trade-offs. There is a growing consensus amongst key forest decision-makers in Bangladesh that traditional forestry is needed to make the transition to more sustainable forestry, which is likely to involve local people in forest management. As a result, the government has initiated a social forestry program from 1981 with the assistance of the Asian Development Bank (ADB) loan and the United Nations Development Program (UNDP) grant and operated mainly in Sal forest areas. The most important objective of this program is to protect, manage, and develop forests in a sustainable way by involving local communities. Although several studies have focused on the management issues of social forestry, none of these studies has evaluated the indicators of sustainable social forestry. The purpose of this study is to evaluate the criteria of sustainable development of social forestry in Bangladesh. The study is based on primary cross-sectional data collected using the multistage stratified sampling technique. In total, 581 social forestry farmers were selected randomly and interviewed using a pre-tested questionnaire. The study evaluated some important components of sustainable development and identified the following conditions of social forestry in Bangladesh:

Reducing Vulnerability of Agriculture and Forestry to Climate Variability and Change: Workshop Summary and Recommendations

The International Workshop on Reducing Vulnerability of Agriculture and Forestry to Climate Variability and Climate Change held in Ljubljana, Solvenia, from 7 to 9 October 2002 addressed a range of important issues relating to climate variability, climate change, agriculture, and forestry including the state of agriculture and forestry and agrometeological information, and potential adaptation strategies for agriculture and forestry to changing climate conditions and other pressures. There is evidence that global warming over the last millennium has already resulted in increased global average annual temperature and changes in rainfall, with the 1990s being likely the warmest decade in the Northern Hemisphere at least. During the past century, changes in temperature patterns have, for example, had a direct impact on the number of frost days and the length of growing seasons with significant implications for agriculture and forestry. Land cover changes, changes in global ocean circulation and sea surface temperature patterns, and changes in the composition of the global atmosphere are leading to changes in rainfall. These changes may be more pronounced in the tropics. For example, crop varieties grown in the Sahel may not be able to withstand the projected warming trends and will certainly be at risk due to projected lower amounts of rainfall as well. Seasonal to interannual climate forecasts will definitely improve in the future with a better understanding of dynamic relationships. However, the main issue at present is how to make better use of the existing information and dispersion of knowledge to the farm level. Direct participation by the farming communities in pilot projects on agrometeorological services will be essential to determine the actual value of forecasts and to better identify the specific user needs. Old (visits, extension radio) and new (internet) communication techniques, when adapted to local applications, may assist in the dissemination of useful information to the farmers and decision makers. Some farming systems with an inherent resilience may adapt more readily to climate pressures, making long-term adjustments to varying and changing conditions. Other systems will need interventions for adaptation that should be more strongly supported by agrometeorological services for agricultural producers. This applies, among others, to systems where pests and diseases play an important role. Scientists have to guide policy makers in fostering an environment in which adaptation strategies can be effected. There is a clear need for integrating preparedness for climate variability and climate change. In developed countries, a trend of higher yields, but with greater annual fluctuations and changes in cropping patterns and crop calendars can be expected with changing climate scenarios. Shifts in projected cropping patterns can be disruptive to rural societies in general. However, developed countries have the technology to adapt more readily to the projected climate changes. In many developing countries, the present conditions of agriculture and forestry are already marginal, due to degradation of natural resources, the use of inappropriate technologies and other stresses. For these reasons, the ability to adapt will be more difficult in the tropics and subtropics and in countries in transition. Food security will remain a problem in many developing countries. Nevertheless, there are many examples of traditional knowledge, indigenous technologies and local innovations that can be used effectively as a foundation for improved farming systems. Before developing adaptation strategies, it is essential to learn from the actual difficulties faced by farmers to cope with risk management at the farm level. Agrometeorologists must play an important role in assisting farmers with the development of feasible strategies to adapt to climate variability and climate change. Agrometeorologists should also advise national policy makers on the urgent need to cope with the vulnerabilities of agriculture and forestry to climate variability and climate change. The workshop recommendations were largely limited to adaptation. Adaptation to the adverse effects of climate variability and climate change is of high priority for nearly all countries, but developing countries are particularly vulnerable. Effective measures to cope with vulnerability and adaptation need to be developed at all levels. Capacity building must be integrated into adaptation measures for sustainable agricultural development strategies. Consequently, nations must develop strategies that effectively focus on specific regional issues to promote sustainable development.

Soil organic matter turnover as a function of the soil clay content: consequences for model applications

Based on a literature review including 201 surface soils from wet, mild, mid-latitude climates and 290 soils from the Lower Saxony soil monitoring programme (Germany), we investigated the relationship between soil clay content and soil organic matter turnover. The relationship was then used to evaluate the clay modifier for microbial decomposition in the organic matter module of the soil–plant–atmosphere model DAISY. A positive relationship was found between soil clay content and soil microbial biomass (SMB) C. Furthermore, a negative relationship was found between soil clay content and metabolic quotient (qCO 2) as an indicator of specific microbial activity. Both findings support the hypothesis of a clay dependent capacity of soils to protect microbial biomass. Under the differing conditions of practical agriculture and forestry, no or only very weak relationships were found between soil clay content and non-living soil organic matter C (humus C). It is concluded that the stabilising effect of clay is much stronger for SMB than for humus. This is in contrast to the DAISY clay modifier assuming the same negative relationship between soil clay content, on the one hand, and turnover of SMB and turnover of soil humus on the other. There is a positive relationship between SMB and microbial decomposition activity under steady-state conditions (microbial growth≈microbial death). The original concept of a biomass-independent simulation of organic matter turnover in the DAISY model must therefore be rejected. In addition to the original modifiers of organic matter turnover, a modifier based on the pool size of decomposing organisms is suggested. Priming effects can be simulated by applying this modifier. When using this approach, the original modifiers are related to specific microbial activity. The DAISY clay modifier is a useful approximation of the relationship between the metabolic quotient (qCO 2) as an indicator of specific microbial activity and soil clay content.

APPLICATION OF APEX FOR FORESTRY

This study was conducted to determine if the Agricultural Policy/Environmental Extender (APEX) model couldreasonably replicate the effects of silvicultural practices on streamflow and loading of sediments and nutrients. APEX wasmodified to enhance factors associated with forestry conditions such as rainfall interception by canopy, litter, subsurface flow,nutrient movement, and routing enrichment ratios. Historical data from the Alto watershed forestry project in east Texas wereused to calibrate and test APEX. The historical data included measured flow, sediment losses, and nutrient (NO3-N, organicN, total N, PO4-P, organic P, and total P) losses from nine small (2.6 to 2.7 ha) watersheds, with three replicates of each ofthe following treatments: (1) clearing, shearing, windrowing, and burning (SHR); (2) clearcutting, roller chopping, and burning(CHP); and (3) undisturbed control watersheds (CON). In addition, the modified APEX model was applied to two of thewatersheds to demonstrate its capabilities in simulating an important sediment source (roads) and an effective best managementpractice (streamside management zones, or SMZs).<br><br>The simulated and measured storm runoff, peak flow rates, and average annual sediment and nutrient losses were inreasonable agreement. Simulated storm runoff per mm of rainfall increased six times for SHR and five times for CHPwatersheds during the first post-treatment year as compared to CON watersheds. Consequently, the sediment concentrationincreased about 13 times for SHR and doubled for CHP watersheds. The nutrient loading also increased during the firstpost-treatment year in SHR and CHP watersheds. However, storm runoff and sediment and nutrient losses were reducedduring the second post-treatment year due to rapid vegetation growth. Storm runoff, along with sediment and nutrient lossesfrom both SHR and CHP watersheds, approached those of CON watersheds during the fourth and fifth post-season years.In general, the modified APEX performance was reasonable considering that forestry losses are generally one or two ordersof magnitude lower than agricultural losses. Further APEX simulations demonstrated that SMZs decreased the averageannual runoff and sediment loss, while forest roads along with greater slope increased runoff and sediment loss from forestedland.

Influence of physiological condition at the time of lifting on the cold storage tolerance and field performance of ash and sycamore

Summary The physiological condition of ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.) seedlings sampled from the same nursery in Ireland was evaluated at periodic intervals from September to May, and after cold (1oC) storage from the time of lifting until May, in 1997/98. Shoot water potential (WP), root electrolyte leakage (REL) and root growth potential (RGP) were assessed. In addition, the survival and height increment of seedlings established in a field trial in tandem with the physiology work was determined after one growing season. Shoot WP of freshly lifted ash seedlings, but not sycamore, decreased to low values in the winter. REL and RGP values were generally also lower in ash than in sycamore on most lift dates. Furthermore, sycamore became more highly active earlier in the year (February/March) than ash (April/May). The effect of cold storage on physiological responses was not consistent. The survival of seedlings in the field was close to 100 per cent regardless of treatment. The height increment of freshly lifted sycamore was best for stock planted from September to early March, whereas ash grew best when planted early (October‐November) or late (after February) in the lifting season, although differences between most lift dates were small in ash. Under operational forestry conditions, planting during some of these periods may not be advisable due to the potential effect of handling damage. Cold-stored ash planted in May after cold storage performed well for seedlings lifted to the store from December to February, but the physiologically more active sycamore performed best when stored from February.

A comparison of three modelling approaches for large-scale forest scenario analysis in Finland

Forests play an important role in the sequestration of carbon dioxide and the storage of carbon. The potential and efficiency of mitigation options in forestry have been studied using large-scale forestry scenario models. In Finland, three models have been applied in attempts to estimate timber production and related carbon budgets. In this study, these models are compared. The oldest, MELA, was designed in the 1970s for the regional and national analysis of timber production. The European Forest Information Scenario Model, EFISCEN, originally a Swedish area matrix model, was developed in the early 1980s. SIMA, a gap-type ecosystem model, was utilised in the 1990s for regional predictions on how the changing climate may affect forest growth and timber yield in Finland. In EFISCEN, only the development of growing stock is endogeneous because the assumptions on growth, and the removal and rules for felling are given exogeneously. In the SIMA model, the rules for felling are exogeneous but the growth is modelled based on individual trees reacting to their environment. In the MELA model, the management of forests is endogeneous, i.e. the growth, felling regimes and the development of growing stock are the results of the analysis. The MELA approach integrated with a process-based ecosystem model seems most applicable in the analyses of effective mitigation measures compatible with sustainable forestry under a changing climate. When using the scenarios for the estimation of carbon budget, the policy makers should check that the analyses cover the whole area of interest, and that the assumptions on growth and management together with the definitions applied correspond with the forestry conditions in question.

Mapping the Policy Terrain: Political Economy, Policy, Environment, and Forestry Production in Northern Mexico

This paper examines the political economy and policy environment of forestry production in northern Mexico. The objective is to review the multiple policy issues that impact forestry production and act together as articulatory mechanisms to move capital from periphery to core. The policies examined that affect forestry emanate from international, national, and state levels.The main point made is that a single event or activity cannot account for existing conditions of forestry in the Sierra Madre Occidental. The purpose is to analyze, perhaps well-known facts by mapping the policy terrain in the context of articulation theory to help scholars and policy makers gain a better understanding of linked social and historical conditions that maintain a political economy. The unique aspect of this presentation is that it brings a political economic, historical, and holistic framework to bear on the problem of policy analyses. Thus, policy formation is viewed from a perspective that considers power interrelations among policies and policy makersKey words: policy, forestry, Mexico, political economy

Heart rate strain in New Zealand manual tree pruners

This report summarises the heart rate strain of six manual contract pruners working in New Zealand plantation forestry conditions. Activity sampling was used to record the subjects' work methods throughout their complete working day. Heart rate data was collected and applied to several heart rate indices in order to determine the strain of manual pruning. An average working heart rate ± standard deviation (SD) of 112 bt.min −1 ± 10.4, a mean relative heart rate of 29% + 7% (SD), a mean ratio of working heart rate to sleeping heart rate of 1.45 ± 0.1 (SD) and a mean 50% working heart rate level of 0.82 ± 0.1 (SD) all indicate that manual pruning can be classified, in terms of heart rate strain, as a moderate workload activity.

Initial deposits, persistence and degradation kinetics of the insect growth regulator, diflubenzuron, in some terrestrial matrices following simulated aerial application

Abstract Initial deposits, persistence and degradation of difiubenzuron [1‐(4‐chlorophenyl)‐3‐(2,6‐difluorobenzoyl) urea] in spruce foliage, forest litter and soil were studied under forestry conditions by applying the chemical as a simulated aerial spray in acetone (DAc) and in fuel oil:Arotex® mixture (DFAr), each at 90 g Al (active ingredient) in 18 L/ha. The residues of diflubenzuron in the substrates were determined by gas‐liquid chromatography, after derivatization as its dimethyl analog. The highest concentrations of the chemical in foliage, litter and soil were 30.6, 4.60 and 3.20 μg/g (fresh wt.), detected at 1 h post‐application of the DFAr formulation. The corresponding concentrations in the three substrates were comparatively low for the DAc formulation. With both formulations, residues found in the substrates correlated well with the droplet density and deposit levels observed on the Kromekote® card/glass plate units placed at ground level. In soil and litter, the residues decreased more rapidly than those in foliage. The half‐lives (d) for the chemical in foliage, litter and soil for the DAc formulation were 9.30, 8.36 and 7.49, respectively; corresponding values for the DFAr formulation were 12.8,7.34 and 6.52 d. Forty‐five days after application, the residue levels in foliage were 3.9 and 0.80 μg/g (fresh wt.) for the DFAr and DAc formulations, respectively; the corresponding residue level for litter for the DFAr formulation was 0.10 μg/g. Litter sprayed with DAc and soil sprayed with DAc and DFAr formulations did not contain detectable levels of the chemical on the 45th day post‐application.

An Ergonomic Evaluation of Douglas Fir Manual Pruning in New Zealand

Abstract This report summarizes the findings of an ergonomic evaluation of first lift manual pruning of Douglas fir under New Zealand plantation forestry conditions. Six subjects were each observed undertaking their normal work methods throughout their complete working day. Heart rate data were collected and analysed using several heart rate indices in order to determine the workload of first lift pruning. The average working heart rate was 112 bt.min−1 ± 10.6 (SD). Results indicate first lift pruning to be a moderate to heavy workload activity. The manual pruning work method may place severe pressures on the workers’ tendons, related bones and nerves of the hand, wrist, and elbow. Alternative pruning methods may contain inherent health and safety risks which must be carefully considered by those involved in the occupation of professional tree pruning.

A Statistical Evaluation of LANDSAT TM and MSS Data for Mapping Forest Cutovers

The cutover area and boundary placement mapping accuracies from currently used air photo techniques and LANDSAT TM and MSS imagery were determined for Alberta forestry conditions. Overall area accuracies for the air photo techniques. LANDSAT TM, and MSS images were 86.7%, 89.5%, and 86.9%, respectively. The influence of increasing accuracy with increasing cutover size, however, must be kept in perspective. Although interpreted cutover areas were generally smaller compared with their actual areas, the deviation was systematic and could therefore be corrected by regression techniques. Overall boundary placement errors for air photo techniques. LANDSAT TM, and MSS images were 30.1, 24.9, and 38.3 m, respectively. Most of the LANDSAT TM errors were in the 20-m range and were within 5 m of the target 15-20 m desired by the Alberta Forest Service. Improvements to this may be achieved by using larger scale satellite images. The base map scale of 1:20 000 was a limiting factor to this study, however, as it was too small with both plotting errors and pen line widths contributing to existing map errors. LANDSAT TM images offered a 12:1 cost savings in data acquisition and are more efficient in comparison with conventional air photos. Use of either medium scale air photos or LANDSAT TM images can be recommended depending on the level of timber commitment accuracy requirements and is presented in the paper as an operational cutover update mapping strategy. Keywords: Forest inventory, update, LANDSAT, change detection, mapping, accuracy analysis, remote sensing.

The Canadian Forestry Corps in Scotland during World War II

Abstract The Canadian Forestry Corps, composed of professional woodsmen, was first organized during World War One at the request of the United Kingdom to help meet Britain's timber needs during the hostilities. It was re‐formed in World War Two to play the same role. Most of its activities were centred in Highland Scotland during the latter conflict though it also participated in the north‐west Europe operations following D‐Day. Some 33 camps were scattered in north‐eastern Scotland, from Berriedale to Brechin, with major concentrations on Deeside, Strathspey and the Moray/Dornoch Firth Lowlands. In addition to meeting its primary objective the Canadian Forestry Corps’ presence in Scotland was influential in other ways: as a defensive element in the earlier years, as a social factor in many smaller communities, and in post‐war forestry conditions through its widespread clearing activities and in the more modern wood‐handling techniques which it introduced.