Ultrafast CT scanning of an oak log for internal defects

Science.gov (United States)

Francis G. Wagner; Fred W. Taylor; Douglas S. Ladd; Charles W. McMillin; Fredrick L. Roder

1989-01-01

Detecting internal defects in sawlogs and veneer logs with computerized tomographic (CT) scanning is possible, but has been impractical due to the long scanning time required. This research investigated a new scanner able to acquire 34 cross-sectional log scans per second. This scanning rate translates to a linear log feed rate of 85 feet (25.91 m) per minute at one...

Yield and ultrasonic modulus of elasticity of red maple veneer

Science.gov (United States)

Robert J. Ross; Steven Verhey; John R. Erickson; John W. Forsman; Brian K. Brashaw; Crystal L. Pilon; Xiping Wang

2004-01-01

The purpose of the study was to assess the potential for using red maple sawlogs to manufacture laminated veneer lumber (LVL). The primary objective was to determine the yield of ultrasonically graded veneer from red maple logs. A sample of 48 logs was obtained from six Eastern and Lake States in the United States. The logs were visually graded and shipped to a plywood...

Three diameter-limit cuttings in West Virginia hardwoods a 5-year report

Science.gov (United States)

Russell J. Hutnik

1958-01-01

Mine timbers are a basic need of West Virginia's giant coal industry. The annual requirement of sawed mine timbers is roughly 250 million board feet. The mines also use a large volume of wood in rough form for props and lagging. Yet, compared to sawlogs and veneer logs, these mine timbers are low-value products. This means that they must be produced at low cost....

Sawlog sizes: a comparison in two Appalachian areas

Science.gov (United States)

Curtis D. Goho; A. Jeff Martin

1973-01-01

Frequency distributions of log diameter and length were prepared for eight Appalachian hardwood species. Data obtained in Ohio, Kentucky, and Tennessee, were compared with information collected previously from West Virginia and New England. With the exception of red oak, significant regional differences were found.

Beech wood export and import trends in Serbia

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Ranković Nenad

2004-01-01

Full Text Available By the establishment and analysis of the model of beech wood export and export trends in Serbia (by quantity and value, for the period 1988-2002 the regularities of the changes of their magnitude in time were defined. On this basis, the relations of import and export trends were analyzed. Based on the study elements, the potentials of beech sawlog and beech sawnwood export, as well as the potential economic effects, were pointed out.

Influence of Lumber Volume Maximization in Sawing Hardwood Sawlogs

Science.gov (United States)

Philip H. Steele; Francis G. Wagner; Lalit Kumar; Philip A. Araman

1993-01-01

The Best Opening Face (BOF) technology for volume maximization during sawing has been rapidly adopted by softwood sawmills. Application of this technology in hardwood sawmills has been limited because of their emphasis on sawing for the highest possible grade of lumber. The reason for this emphasis is that there is a relatively large difference in price between the...

Influence of Lumber Volume Maximization on Value in Sawing Hardwood Sawlogs

Science.gov (United States)

Philip H. Steele; Francis G. Wagner; Lalit Kumar; Philip A. Araman

1992-01-01

Research based on applying volume-maximizing sawing solutions to idealized hardwood log forms has shown that average lumber yield can be increased by 6 percent. It is possible, however, that a lumber volume-maximizing solution may result in a decrease in lumber grade and a net reduction in total value of sawn lumber. The objective of this study was to determine the...

Crown releasing of red maple poles to shorten high-quality sawlog rotations

Science.gov (United States)

Gayne G. Erdmann; Ralph M., Jr. Peterson; Robert R. Orberg

1985-01-01

The effects of six crown-release treatments on growth and bole quality development of 54-year-old dominant, codominant, and intermediate red maples (Acer rubrum L.) were evaluated on a good red maple site (site index = 19.3 mat 50 years) in upper Michigan. Results showed that crown release stimulated the growth of dominants, codominants, and strong...

Productivity and cost of harvesting a stemwood biomass product from integrated cut-to-length harvest operations in Australian Pinus radiata plantations

International Nuclear Information System (INIS)

Walsh, D.; Strandgard, M.

2014-01-01

Significant quantities of woody biomass from the tops of trees and larger woody ‘waste’ pieces that fall outside existing sawlog and pulpwood specifications are left on site post final harvest in Australian radiata Pinus radiata (D. Don) (radiata pine) plantations. Woody biomass is a potential product for pulp making or energy generation. Commercial use of woody biomass from radiata pine plantations would add extra value to the Australian plantation estate through improved resource utilisation, and potentially reduced post-harvesting silvicultural costs. This study investigated the productivity and cost impact of the harvest and extraction to roadside of woody biomass in an integrated harvest operation in a typical Australian two machine (harvester/processor and forwarder), cut-to-length, clearfall operation in a mature, thinned radiata pine plantation. The harvest operation yielded 23 GMt/ha (5% of the total yield) of woody biomass (known as ‘fibreplus’), 443 GMt/ha of sawlogs and 28 GMt/ha of pulpwood. The mean quantity of biomass left on site was 128 GMt/ha, mainly consisting of branches and needles, sufficient to minimise nutrient loss and protect the soil from erosion. Woodchips derived from the fibreplus product were suitable for kraft pulp making, (when blended in small amounts with clean de-barked roundwood woodchips), and for energy generation. The method trialed with the fibreplus product being produced did not impact harvesting and processing productivity and costs, but extraction was 14% less productive. Through analysis of the productivities of each phase and development of a cost model the harvest and extraction of the fibreplus product was estimated to increase total unit costs by ∼4.9%. - Highlights: • Study of the productivity and cost impact of producing a woody biomass product. • We compared two scenarios – harvesting with and without the biomass product. • An additional 23 GMt/ha (5% of the total yield) of woody biomass

Adjusting Quality index Log Values to Represent Local and Regional Commercial Sawlog Product Values

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Orris D. McCauley; Joseph J. Mendel; Joseph J. Mendel

1969-01-01

The primary purpose of this paper is not only to report the results of a comparative analysis as to how well the Q.I. method predicts log product values when compared to commercial sawmill log output values, but also to develop a methodology which will facilitate the comparison and provide the adjustments needed by the sawmill operator.

Effect of logging wounds on diameter growth of sawlog-size Appalachian hardwood crop trees

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Neil I. Lamson; H. Clay Smith; H. Clay Smith

1988-01-01

In previously thinned, even-aged Appalachian hardwood stands, 5-year diameter growth of 102 wounded and 102 unwounded codominant crop trees were compared. A wounded crop tre was defined as one with at least one exposed sapwood logging wound at least 100 inch2 in size. An unwounded crop tree of the same species and size was selected near each of the 102 wounded trees....

Impacts of changing hardwood lumber consumption and price on stumpage and sawlog prices in Ohio

Science.gov (United States)

William Luppold; Matthew Bumgardner; T. Eric. McConnell

2014-01-01

In the early 2000s, increasing US furniture imports preceded declining US hardwood lumber demand and price. In the summer of 2002, however, hardwood lumber prices started to increase as demand by construction industries increased. By the mid-2000s, hardwood lumber prices hit all-time highs. Lumber prices hit all-time highs for red oak (Quercus spp...

Young children’s learning of relational categories:multiple comparisons and their cognitive constraints

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Jean-Pierre eThibaut

2015-05-01

Full Text Available Relational categories are notoriously difficult to learn because they are not defined by intrinsic stable properties. We studied the impact of comparisons on relational concept learning with a novel word learning task in 42-month-old children. Capitalizing on Gentner et al. (2011, two, three or four pairs of stimuli were introduced with a novel relational word. In a given trial, the set of pairs was composed of either close or far pairs (e.g., close pair: knife1-watermelon, knife2-orange, knife3-slice of bread and knife4-meat; far pair: ax-evergreen tree, saw-log, cutter-cardboard and knife-slice of bread, for the cutter for relation. Close pairs (2 vs. 3 vs. 4 pairs led to random generalizations whereas comparisons with far pairs gave the expected relational generalization. The 3 pair case gave the best results. It is argued that far pairs promote deeper comparisons than close pairs. As shown by a control experiment, this was the case only when far pairs display well known associations.

Appalachian hardwood stump sprouts are potential sawlog crop trees. Research note NE-299. [Oak, maple, linden, cherry trees

Energy Technology Data Exchange (ETDEWEB)

Lanson, N.I.

1976-01-01

Dbh and height of 8- and 12-year-old coppice shoots and the number of live shoots were recorded for 736 stumps at least 12 inches in diameter of Liriodendron tulipifera, Prunus serotina, Quercus rubra, Acer rubrum, and Tilia americana in north-central West Virgina. Of the 8-year-old shoots, T. americana had the greatest number of live stems/stump (16.8) and the greatest number of potential crop trees (dominant or co-dominant shoots attached to the stump not more than 6 inches above the ground), averaging 2.5 stems/stump. The average numbers of potential crop trees/stump were similar at 8 and 12 year. At 12 years, at least 88% of stumps of each species had at least one stem of groundline origin with no forks below 25 feet were 84% for L. tulipifera, 59% for Q rubra, 73% for A. rubrum, and 65% for P. Serotina.

The effect of curve sawing two-sided cants from small diameter hardwood sawlogs on lumber and pallet part yields

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Peter Hamner; Marshall S. White; Philip A. Araman

2006-01-01

Curve sawing is a primary log breakdown process that incorporates gang-saw technology to allow two-sided cants from logs with sweep to be cut parallel to the log surface or log axis. Since curve-sawn logs with sweep are cut along the grain, the potential for producing high quality straight-grain lumber and cants increases, and strength, stiffness, and dimensional...

Possible effects of the hurricane Gudrun on the regional Swedish forest energy supply

International Nuclear Information System (INIS)

Bjoerheden, Rolf

2007-01-01

This paper presents a snapshot speculative analysis of some possible effects of the massive windthrow in south Sweden on January 8-9, 2005. Hurricane Gudrun damaged buildings and blocked roads, making large areas inaccessible except by helicopter. Electricity and telecommunications were shambolic. Around 70 million cubic metres were windthrown, equalling a 'normal' Swedish annual felling-a gross value exceeding EUR20,000,000,000. The paper presents the subsequent restoration work that has placed a special focus on the forest sector. In south Sweden, logging work will last for a couple of years. The roundwood market will be severely strained. For individual forest owners, the economic effects of the storm are often disastrous. To ensure that forest owners will retrieve at least part of the pre-storm forest value, restoration aims at the salvaging of maximum value. Sawmills try to store the most valuable timber for years to come, decreasing the risk of painful capacity adjustments and protecting export opportunities. Forest fuel value is low compared to sawlogs and pulpwood. Thus, the forest energy sector has received little attention. Forest chippers normally contribute important marginal quantities of wood fuels, but since no logging residues will be harvested from the windthrown forests for a period of 2-3 years, they are put out of business and may disappear from the market. Heating and power plants will receive an abundance of industrial by-products in the coming 2-3 years, followed by a period of expected shortage of woody biomass for energy production. With few forest chippers left, the situation will be troublesome. (author)

Long-term development of nursing mixtures of Sitka spruce and larch species in an experiment in northern Scotland

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William L. Mason

2014-12-01

Full Text Available Aim of the study: An experiment was established in 1966 to compare the growth and development of 50: 50 mixtures of Sitka spruce (Picea sitchensis with either Japanese larch (Larix kaempferi or tamarack (L. laricina with that found in pure plots of Sitka spruce. The site was one of moderate nitrogen availability where the presence of heather (Calluna vulgaris could be expected to limit the growth ofSitka spruce.Area of the study: North-east Scotland.Material and methods: There were different patterns of spruce growth in the pure plots and in the mixtures, with faster spruce growth in mixture in the years approaching and immediately following canopy closure (i.e. ages 15-25. Foliage analysis suggested that this was linked with improved nitrogen status of spruce trees in the mixed compared to the pure plots.Main results: At years 20 and 25 there were significant differences in height, diameter, and basal area between treatments, with the largest basal area being found in the Japanese larch/Sitka spruce mixtures, indicative of overyielding in the mixed plots. However, when the experiment was clearfelled at 41 years of age, all treatments had self-thinned to produce spruce dominated stands of similar height with only an occasional larch tree surviving in plots that were originally 50:50 mixtures.Research highlights: There were no differences between treatments in basal area, harvested volume or sawlog outturn after 41 years. These results can be interpreted as showing facilitation between the larch and the spruce during the establishment phase followed by competition for light once canopy closure had occurred.Keywords: Mixed stand dynamics; facilitation; nitrogen status; product outturn.

Overview and forecast on forestry productions worldwide.

Science.gov (United States)

Wenjun, Zhang

2007-02-01

Our world is largely dependent upon the forestry productions. Through the exploitation of forest reserves, we manufacture various industrial products, furniture, and obtain fuel and energy. Forestry productions should be conducted without large-scale deforestation and environmental degradation. In present study we perform a review and forecast analysis on forestry productions worldwide, with the objectives of providing an insight into the trend for several types of forestry productions in the future, and providing referential data for sustainable forestry productions and environmental management. Polynomial functions are used to fit trajectories of forestry productions since 1961 and forecasts during the coming 20 years are given in detail. If the past pattern continues, world fibreboard production would dramatically grow and reach 224,300,000 +/- 44,400,000 m(3) by the year 2020, an increase up to 240.7 to 408.9% as compared to the present level. Roundwood production of the world would change by -55.5 to 70.4% and reach 3,526,600,000 +/- 2,066,800,000 m(3) by 2020. In 2020 world production of sawlogs and veneer logs would change by -100 to 164.6% and reach 1,212,900,000 +/- 1,242,600,000 m(3). Global wood fuel production would change by -68.9 to 1.4% and reach 1,130,900,000 +/- 600,800,000 m(3) by 2020. Forestry productions in developed countries would largely surpass productions in developing countries in the near future. World forestry production grew since 1961 excluding wood fuel. Roundwood and wood fuel account for the critical proportions in the forestry productions. Wood fuel production has being declined and rapid growing of roundwood production has slowed in recent years. Widespread use of regenerative wood substitutes and worldwide afforestation against deforestation will be among the most effective ways to reduce deforestation and environment degradation associated with forestry productions.

Net carbon dioxide emissions from alternative firewood-production systems in Australia

International Nuclear Information System (INIS)

Paul, K.I.; Booth, T.H.; Jovanovic, T.; Polglase, P.J.; Elliott, A.; Kirschbaum, M.U.F.

2006-01-01

The use of firewood for domestic heating has the potential to reduce fossil-fuel use and associated CO 2 emissions. The level of possible reductions depends upon the extent to which firewood off-sets the use of fossil fuels, the efficiency with which wood is burnt, and use of fossil fuels for collection and transport of firewood. Plantations grown for firewood also have a cost of emissions associated with their establishment. Applying the FullCAM model and additional calculations, these factors were examined for various management scenarios under three contrasting firewood production systems (native woodland, sustainably managed native forest, and newly established plantations) in low-medium rainfall (600-800mm) regions of south-eastern Australia. Estimates of carbon dioxide emissions per unit of heat energy produced for all scenarios were lower than for non-renewable energy sources (which generally emit about 0.3-1.0kgCO 2 kWh -1 ). Amongst the scenarios, emissions were greatest when wood was periodically collected from dead wood in woodlands (0.11kgCO 2 kWh -1 ), and was much lower when obtained from harvest residues and dead wood in native forests ( 2 kWh -1 ). When wood was obtained from plantations established on previously cleared agricultural land, use of firewood led to carbon sequestration equivalent to -0.06kgCO 2 kWh -1 for firewood obtained from a coppiced plantation, and -0.17kgCO 2 kWh -1 for firewood collected from thinnings, slash and other residue in a plantation grown for sawlog production. An uncertainty analysis, where inputs and assumptions were varied in relation to a plausible range of management practices, identified the most important influencing factors and an expected range in predicted net amount of CO 2 emitted per unit of heat energy produced from burning firewood. (author)

Accounting for density reduction and structural loss in standing dead trees: Implications for forest biomass and carbon stock estimates in the United States

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Domke Grant M

2011-11-01

Full Text Available Abstract Background Standing dead trees are one component of forest ecosystem dead wood carbon (C pools, whose national stock is estimated by the U.S. as required by the United Nations Framework Convention on Climate Change. Historically, standing dead tree C has been estimated as a function of live tree growing stock volume in the U.S.'s National Greenhouse Gas Inventory. Initiated in 1998, the USDA Forest Service's Forest Inventory and Analysis program (responsible for compiling the Nation's forest C estimates began consistent nationwide sampling of standing dead trees, which may now supplant previous purely model-based approaches to standing dead biomass and C stock estimation. A substantial hurdle to estimating standing dead tree biomass and C attributes is that traditional estimation procedures are based on merchantability paradigms that may not reflect density reductions or structural loss due to decomposition common in standing dead trees. The goal of this study was to incorporate standing dead tree adjustments into the current estimation procedures and assess how biomass and C stocks change at multiple spatial scales. Results Accounting for decay and structural loss in standing dead trees significantly decreased tree- and plot-level C stock estimates (and subsequent C stocks by decay class and tree component. At a regional scale, incorporating adjustment factors decreased standing dead quaking aspen biomass estimates by almost 50 percent in the Lake States and Douglas-fir estimates by more than 36 percent in the Pacific Northwest. Conclusions Substantial overestimates of standing dead tree biomass and C stocks occur when one does not account for density reductions or structural loss. Forest inventory estimation procedures that are descended from merchantability standards may need to be revised toward a more holistic approach to determining standing dead tree biomass and C attributes (i.e., attributes of tree biomass outside of sawlog