Pulpwood Harvesting Research Articles

An empirical financial analysis of integrating biomass procurement in sawtimber and pulpwood harvesting in eastern Canada

Integrating forest biomass procurement in wood procurement for conventional products is a potential means of reducing bioenergy system supply costs. We studied forest harvest operations to procure biomass in the form of trees and tree sections, along with sawtimber and pulpwood. We evaluated the cost-effectiveness of the supply chain with a particular focus on harvest costs and the potential silvicultural savings from a reduced need for site preparation and reforestation. We compared four wood procurement scenarios of increasing intensity (from harvesting only sawtimber to harvesting sawtimber, pulpwood and biomass for bioenergy) at three sites in eastern Canada. Wood procurement intensity did not affect feedstock unit costs (CAD·m−3). At the stand scale, procuring biomass for bioenergy had limited impact on harvest costs (CAD·ha−1) for low-density stands with large trees. In contrast, high-density stands with small trees generated more feedstock for bioenergy (up to 50 m3·ha−1), but biomass procurement increased harvest costs. The cost-effectiveness of the wood supply chain did not vary significantly along the wood procurement intensity gradient we studied when silvicultural savings are considered. The proportion of biomass harvested, stand characteristics, and market conditions proved to be important factors that influence wood procurement profitability.

Potential complementarity between forest carbon sequestration incentives and biomass energy expansion

There is a growing literature on the potential contributions the global forest sector could make toward long-term climate action goals through increased carbon sequestration and the provision of biomass for energy generation. However, little work to date has explored possible interactions between carbon sequestration incentives and bioenergy expansion policies in forestry. This study develops a simple conceptual model for evaluating whether carbon sequestration and biomass energy policies are carbon complements or substitutes. Then, we apply a dynamic structural model of the global forest sector to assess terrestrial carbon changes under different combinations of carbon sequestration price incentives and forest bioenergy expansion. Our results show that forest bioenergy expansion can complement carbon sequestration policies in the near- and medium-term, reducing marginal abatement costs and increasing mitigation potential. By the end of the century these policies become substitutes, with forest bioenergy expansion increasing the costs of carbon sequestration. This switch is driven by relatively high demand and price growth for pulpwood under scenarios with forest bioenergy expansion, which incentivizes management changes in the near- and medium-term that are carbon beneficial (e.g., afforestation and intensive margin shifts), but requires sustained increases in pulpwood harvest levels over the long-term.

Effect of slope on productivity and cost of Eucalyptus pulpwood harvesting using single-grip purpose-built and excavator-based harvesters

ABSTRACT With the emergence of excavator-based harvesters in cut-to-length CTL operations as a potential alternative to purpose-built harvesters, a debate has been opened as to which machine type is the most suitable in the forestry environment. A mechanized Eucalyptus pulpwood CTL operation, was observed to determine the effect of slope on harvester productivity and cost. A 2 × 2 factorial design with two treatments (machine type) against slope and individual tree volume as factors was developed. Two machine types were studied, an excavator-based harvester (Volvo EC210BF), and a purpose-built harvester (TimberPro TL725B), both fitted with Maskiner SP 591 LX harvester heads. A single operator with significant experience on both machines was used throughout the study. The machines worked on a range of slopes, from level to 50% in two separate corridors containing trees of similar volume and form. Continuous slope data was derived using large footprint light detection and ranging (LiDAR) data of the area. Calculations were carried out on each machine to determine which machine was more cost-effective. The productivity of the excavator based harvester decreased by 0.048 m3PMH−1 for every 1% increase in slope, while the productivity of the purpose-built harvester was constant across slope. While the purpose-built harvester was found to have a higher mean productivity the excavator-based harvester was more economical. This suggests that, in terms of economics the excavator-based harvester was more suitable across the conditions encountered in this study.

Residual biomass recovery from fully-mechanized delayed thinnings on Spanish Pinus spp. plantations

In Spain, five million hectares of conifer plantations require thinning. As only a small part produces pulpwood, they are a major potential biomass resource. A time-study is performed on the recovery of logging residues in a Pinus plantation on gentle terrain in order to analyze the main factors affecting the productivity and cost of biomass and pulpwood harvesting. The first factor is the branches and tops piling method, either using the forest harvester head to bunch them along the strip road sides (method S) while processing the timber, or leaving them on the strip road centre (method C) and using a 175 HP bulldozer with a raking implement to pile them up afterwards. The second factor is the top diameter separating pulpwood and biomass, 8 or 10 cm. Mechanized felling-processing productivity is greater for the method C and the smaller diameter. Hauling biomass off with forwarder is also significantly more productive when piled by bulldozer. Productivity equations were fitted for pulpwood and biomass forwarding. The direct cost of biomass recovery ranged from €29.7 to €31.5 per green tonne (H = 51%). The roundwood and biomass effective yields – per hectare – were measured. This allowed evaluating the cost balance for roundwood/roundwood plus biomass harvesting, based on the net income per hectare. Under the 2013 Spanish market conditions, recovery of residual biomass is economically preferable to harvesting only roundwood in the studied stands. The greater net income balance corresponds to the piling method using the bulldozer (C) and the larger top diameter (10 cm).

Productivity and cost evaluations of energy-wood and pulpwood harvesting systems in first thinnings

In an environment where increases in both energy-wood and pulpwood production are desired, examining and differentiating forest energy-wood and pulpwood production systems based on their productivity and associated costs may allow potential users to better identify where cost savings may be realized, depending on their desired management preference. The cost-effectiveness of pulpwood and energy-wood harvesting systems may ultimately be determined by the productivity of the system in use and an variety of other factors, which include site conditions (i.e. stem size and removal per hectare) and market prices for raw material. An analysis of six different harvesting methods for energy-wood and pulpwood production was carried out to determine how productive and cost-effective selected systems may be and how they compare. Cost calculations, limited to production costs, indicated that the most cost-efficient harvesting methods among the tested methods in early thinnings at a diameter at breast height of removal less than 15 cm were integrated harvesting with multi-tree handling and delimbed stemwood harvesting with multi-tree handling aggregating all cutting fractions within the same pile. The results also suggest pulpwood harvesting with single-tree processing in stands with larger trees (diameter at breast height of removals > 15–17 cm), where this cutting method is cost-effective.

Opportunities for cost mitigation and efficiency improvements through rationalization of small-diameter energy wood supply chains

The production of energy wood from small-diameter (DBH < 9 cm) forests in Finland through separate energy wood and integrated energy wood and pulpwood production often face cost pressures that inhibit economic viability of many operations. Systemic factors, such as small stem sizes, limited removals, and high density of young forest stands limit the efficiency of many operations resulting in low productivity and high operating costs, particularly within cutting operations. Within the study, means to increase efficiency and mitigate costs of small-diameter energy wood and integrated energy wood and pulpwood operations by identifying optimal methods, technologies, and policy that may be applied were identified. Studies of integrated and delimbed stemwood cutting methods including the use of multi-tree handling and combined timber assortments in forest stands with stem size (DBH) of removals varying between 5-17 cm were investigated and compared against separate pulpwood production. Findings suggest that the methods provide increases in productivity and decreases in costs, particularly in < 11 cm DBH conditions. Crane scale measuring was investigated as a technical solution in timber logistics to be applied in energy wood and industrial roundwood procurement. The measuring method, used as a basis of payment, was found to provide a reliable, accurate, and cost effective method when compared with a manual timber pile measurement system. Policies, in the form of financial incentives were investigated to determine the effects of applicable subsidies on the profitability of energy wood production based on stem size of removal, finding possibilities for profitable operations with reduction in subsidies, however, with stem sizes (DBH) of removal 7 cm incentives played an important role in increasing profitability. Cost reductions were identified through: The utilization of integrated and delimbed stemwood harvesting methods with multi-tree handling, decreasing harvesting costs by 0.152.4% dependent on stem size (DBH) of removal between 7-17 cm when compared to a traditional pulpwood harvesting method; Combining timber assortments providing harvesting cost reductions between 1.5-8.0% between 5-17 cm; Crane scale measurement use provided increased accuracy and a 18.2-45.5% reduction in costs when compared to a manual timber pile measurement system when dependent on estimated working volumes between 20,000-30,000 m; Financial incentives under the PETU system were applied increasing profit margins of integrated supply chain operations by 3.8-19.9% dependent on stem size of removal, particularly with stem size of removals between 5-7 cm. Through rationalization of supply chains, harvesting methods, technologies, and policy which exhibit the ability to reduce costs and should be utilized throughout the whole supply chain where implementation is possible.

Excavator technology for increasing the efficiency of energy wood and pulp wood harvesting

Abstract In Finland, the harvesting of small-sized thinning wood will be doubled or even tripled over the current harvesting volume. A greater area of peatlands could be harvested during winter for energy and pulpwood if contractors adopted more carriers for harvester heads based on excavator technology. The purpose of this study was to investigate why excavator-based harvesters are not used more widely for wood harvesting in these forests. The study was implemented by conducting 46 personal interviews in 2006 and 2011. The interviewees formed five groups: contractors who used excavators for harvesting, contractors who owned excavators but did not use them for harvesting, harvester head manufacturers, officers of wood procurement organizations, and vendors of excavators. The Nordic tradition of timber harvesting using wheeled harvesters was the main reason for the limited use of excavator-based harvesters. In the follow-up (2011) lack of the forest-adapted excavators was the main reason. During this study, mixes of harvesting machines have not been increased to permit winter wood procurement, even though the number of annual working hours could be increased for both excavator-based and wheeled harvesters. Existing excavators could be used more efficiently by cooperating with energy and forest industry as well as with Forest Owners’ Associations. In future, the potential of excavator technology could be realised by developing a more flexible Finnish wood procurement infrastructure that uses a wider range of harvesters in harvesting enterprises. This could also increase the overall cost efficiency of wood procurement by permitting the use of less expensive harvesting machines.

Renewable energy targets, forest resources, and second‐generation biofuels in Finland

AbstractIntroduction of second‐generation biofuels is an essential factor for meeting the EU's 2020 targets for renewable energy in the transport sector and enabling the more ambitious targets for 2030. Finland's forest industry is strongly involved in the development and commercializing of second‐generation biofuel production technologies. The goal of this paper is to provide a quantified insight into Finnish prospects for reaching the 2020 national renewable energy targets and concurrently becoming a large‐scale producer of forest‐biomass‐based second‐generation biofuels feeding the increasing demand in European markets. The focus of the paper is on assessing the potential for utilizing forest biomass for liquid biofuels up to 2020. In addition, technological issues related to the production of second‐generation biofuels were reviewed. Finland has good opportunities to realize a scenario to meet 2020 renewable energy targets and for large‐scale production of wood‐based biofuels. In 2020, biofuel production from domestic forest biomass in Finland may reach nearly a million ton (40 PJ). With the existing biofuel production capacity (20 PJ/yr) and the national biofuel consumption target (25 PJ) taken into account, the potential net export of biofuels from Finland in 2020 would be 35 PJ, corresponding to 2–3% of European demand. Commercialization of second‐generation biofuel production technologies, high utilization of the sustainable harvesting potential of Finnish forest biomass, and allocation of a significant proportion of the pulpwood harvesting potential for energy purposes are prerequisites for this scenario. Large‐scale import of raw biomass would enable remarkably greater biofuel production than is described in this paper. © 2011 Society of Chemical Industry and John Wiley &amp; Sons, Ltd

Productivity of whole-tree bundler in energy wood and pulpwood harvesting from early thinnings

First thinnings have been neglected to great extent in Finland because of high harvesting costs. The whole-tree bundler (Fixteri) was developed in order to rationalize the integrated harvesting of small-diameter energy wood and pulpwood and to reduce transportation costs through load compaction. The operation of the whole-tree bundler is composed of cutting and compaction processes. In the present study, the productivity level and the performance characteristics of the second version of the whole-tree bundler (Fixteri II) in integrated energy wood and pulpwood harvesting from first thinnings were defined on the basis of a time study. When the mean volume of removed whole trees averaged 20 dm3 at the stand, the productivity of Fixteri II per effective working (E0 excluding delays) hour was 3.4 m3/(E0) and with an average removal of 75 dm3, it was 6.1 m3/(E0). When compared with the first prototype of the whole-tree bundler (Fixteri I), the productivity of Fixteri II was 38–77% higher, depending on the stand density and mean tree volume of the removal. The higher performance level of Fixteri II stemmed mainly from the increase in multi-tree cutting and from the introduction of grapple feeding of the bunches. Furthermore, the better hydraulic capacity of the base machine enabled a higher level of simultaneous working processes.

Integrated harvesting of energy wood and pulpwood in first thinnings using the two-pile cutting method

In order to increase the harvesting volumes of energy wood and pulpwood from first thinnings, harvesting costs have to be reduced significantly. Metsäteho Oy studied the integrated harvesting of pulpwood and energy wood based on a two-pile method, where industrial roundwood (pulpwood) and energy wood fractions are stacked into two separate piles when cutting a first-thinning stand. The productivity and cost levels of the integrated, two-pile cutting method were determined, and the harvesting costs of the two-pile method were compared with those of conventional separate wood harvesting methods. In the time studies, when the size of removal was 50 dm 3 , the productivity in conventional whole-tree cutting was 6% higher than in integrated cutting. With a stem size of 100 dm 3 , the productivity of whole-tree cutting was 7% higher than in integrated cutting. The results indicated, however, that integrated harvesting based on the two-pile cutting method enables harvesting costs to be decreased to below the current cost level of separate pulpwood harvesting in first-thinning stands. The greatest cost-saving potential lies in small-sized ( d 1.3 = 7–11 cm) first thinnings. The costs of forest haulage after integrated pulpwood and energy wood cutting were higher than those of separate wood harvesting because of lower removals in integrated harvesting. The results showed that when integrated wood harvesting is based on the two-pile cutting method, the removals of both energy wood and pulpwood should be more than 20–25 m 3 ha −1 at the integrated harvesting sites in order to achieve economically viable integrated procurement.

Energy wood harvesting productivity of three harvesting methods in first thinning of scots pine (Pinus sylvestris L.)

Abstract Energy wood harvesting in young forests presents an economical challenge and has been dependent on subsidies in Finland. Whole-tree harvesting systems have proved to be most productive when carrying out energy wood harvesting in cleanings and early thinnings in young forests. The application of integrated energy wood and pulpwood harvesting is less common. It was hypothesized that multi-tree harvesting (MTH) with the OM-Waratah 745 single grip harvester head could change harvesting logistics and improve productivity for integrated energy wood and pulpwood thinnings. Two variations of MTH were compared with single-tree harvesting (STH). The logging methods studied were: (1) conventional single-tree harvesting with pulpwood and energy wood processed at the strip road; (2) multi-tree harvesting with pulpwood and energy wood processing along the strip road (MTH1); and (3) multi-tree harvesting at the stump where the aim was to leave the logging residues distributed evenly over the harvesting area and not on the strip roads (MTH2). MTH methods were 28–35% more productive than the single-tree harvesting. The biggest differences in work stages were found in the felling and delimbing stages. In single-tree harvesting felling was 9–26% and delimbing 14–27% slower than in multi-tree harvesting. MTH2 distributed 13% of residues further than 7 m from the strip road center. With STH and MTH1 only a good 1.2–1.7% was placed this far, and 74.4 and 62.0% respectively within 3 m.

“Things Was Different in the South”: The industrialization of pulpwood harvesting systems in the Southeastern United States 1945–1995

By contrast with Eastern Canada, it took a long time for mechanized systems to transform woods work in the American Southeast. The Southeast experienced a more episodic, delayed and less complex transformation of woods work, one marked by ‘making do”, incremental innovations, simpler systems, a reliance on the adaptation of ideas and machines developed elsewhere, and the tendency for a single harvesting system to dominate use over long periods of time. We argue the social, economic and environmental conditions of the Southeast after 1945 facilitated a laissez-faire attitude to pre-industrial harvesting methods by pulp and paper mill owners. The most important of these conditions was that alternative employment for rural African-Americans was slow to develop, leaving a large source of cheap, available labour for woods work. Pulp mill owners were able to outsource the provision of wood to small contractors through a network of local intermediaries called “wood dealers”. The wood supply system created by pulp mill owners placed the costs of innovation into the hands of the poorly capitalized harvesting contractors. This wood supply system delivered mill owners wood at very low prices, but it effectively inhibited steady and thoroughgoing innovation for many years.

Clean Chip Residual as a Substrate for Perennial Nursery Crop Production

Abstract Pine bark (PB) for horticultural uses is becoming less available and as a result, there is a need to develop alternative substrates for continued profitability of the nursery industry. This study, conducted at Poplarville, MS, and Auburn, AL, evaluated the growth of nine perennial species in a substrate composed of a pulpwood harvesting by-product called clean chip residual (CCR) which contains approximately 50% wood fiber. Two CCR particle sizes were used alone or amended with peat moss (PM) (4:1 by vol) and compared with control treatments PB and PB:PM. Substrates composed of 100% PB or 100% CCR had high air space (AS) and low water holding capacity (WHC) which resulted in less available water to plants. Addition of PM lowered AS and increased WHC. There were no significant differences among growth indices at Poplarville for 6 of 8 species and for 3 of 7 species at Auburn, though the remaining 4 species were only slightly smaller when grown in 100% CCR. Shoot dry weight was greatest in substrates amended with PM. Results of this study indicate that acceptable growth of perennial plants can be obtained in substrates composed of CCR when compared to PB and PB amended with PM.

Energy wood and pulpwood harvesting from young stands using a prototype whole-tree bundler

The productivity of cutting and bundling whole trees using the first prototype of a bundle-harvester comprised of a harwarder as the base machine, an accumulating felling head, and a compacting device was studied in three young stands in order to facilitate the further development of the concept. In addition, the removal and its composition were studied as a means of laying the foundations for developing methods for work rating and measurement on delivery. Bundling enables in-depth integration of pulpwood and energy wood procurement. Both energy wood (crown biomass) and pulpwood can be incorporated into the same bundles, and the subsequent separation of these fractions takes place at the debarking phase at the pulpmill. Bundle-harvesting productivities were relatively low (2.8–3.7 m/E-h) when compared to current harvesting technology. Improving working techniques, machine structure, and components showed great potential for increasing the efficiency of the concept. The bundles were dimensionally uniform. Their solid volume varied between 0.350 m and 0.513 m, depending on the bundle assortment and stand properties. Integrating energy wood harvesting with pulpwood harvesting increased removal even by 59 per cent.3033

Nest Survival of Forest Birds in the Mississippi Alluvial Valley

In the Mississippi Alluvial Valley, flood control has led to a drastic reduction in the area of forest habitat and altered the patchwork of forest cover types. Silvicultural management of the remaining fragmented forests has changed to reflect the altered hydrology of the forests, current economic conditions of the area, and demand for forest products. Because forest type and silvicultural management impact forest birds, differences in avian productivity within these forests directly impact bird conservation. To assist in conservation planning, we evaluated daily nest survival, nest predation rates, and brood parasitism rates of forest birds in relation to different forest cover types and silvicultural management strategies within this floodplain. Within bottomland hardwood forests, nest success of blue-gray gnatcatcher (Polioptila caerulea, 13%), eastern towhee (Pipilo erythrophthalmus, 28%), indigo bunting (Passerina cyanea, 18%), northern cardinal (Cardinalis cardinalis, 22%), and yellow-billed cuckoo (Coccyzus americanus, 18%) did not differ from that within intensively managed cottonwood plantations. However, average daily survival of 542 open-cup nests of 19 bird species in bottomland hardwoods (0.9516 ± 0.0028, ∼27% nest success) was greater than that of 543 nests of 18 species in cottonwood plantations (0.9298 ±0.0035, ∼15% nest success). Differences in daily nest survival rates likely resulted from a combination of differences in the predator community-particularly fire ants (Solenopsis invicta)-and a marked difference in species composition of birds breeding within these 2 forest types. At least 39% of nests in bottomland hardwood forests and 65% of nests in cottonwood plantations were depredated. Rates of parasitism by brown-headed cowbirds (Molothrus ater) were greater in managed cottonwoods (24%) than in bottomland hardwoods (9%). Nest success in planted cottonwood plantations for 18 species combined (∼14%), and for yellow-breasted chat (Icteria virens, 7%), eastern towhee (14%), indigo bunting (14%), and northern cardinal (17%) did not differ from nest success in cottonwood plantations that were coppiced from root sprouts following pulpwood harvest. Within bottomland hardwood forests, uneven-aged group-selection timber harvest reduced the combined daily nest survival of all species from 0.958 to 0.938, which reduced nest success by about 14%. Specifically, timber harvest reduced nest success of species that nest in the forest midstory and canopy, such as Acadian flycatcher (Empidonax virescens)-from 32% before harvest to 14% after harvest. Conversely, those species that nest primarily in the shrubby understory-such as northern cardinal-were not affected by timber harvest and maintained an overall nest success of about 33%. Thus, birds nesting in the understory of bottomland hardwood forests are not adversely impacted by selective timber harvest, but there is a short-term reduction in nest success for birds that nest in the canopy and midstory.

Loblolly Pine (Pinus taeda) Irregular Shelterwood Stand Development and Red-Cockaded Woodpecker Management—A Case Study

Abstract The overstory and midstory of a loblolly pine (Pinus taeda) irregular shelterwood stand in the Coastal Plain of South Carolina were inventoried 17 yr after a sawtimber and pulpwood harvest and again 12 yr later. At the time of the first inventory, a dense (2482 stems ha-1), small (7.3 cm average dbh, 7.9 m average height) midstory pine population had developed underneath a relatively sparse (10.4 m² ha-1), tall (24 m)pine overstory. Although 38% of the midstory stems and 9% of the overstory stems died during the 12 yr study period, the stand was too dense to have any value as a red-cockaded woodpecker (Picoides borealis) colony site even though the overstory pines survived in sufficient numbers and were large enough to provide potential cavity trees. The stand had ample basal area and stocking of pines greater than 25 cm dbh to be acceptable foraging habitat. Extrapolating the 1987 diameter distribution 12 growing seasons indicated that the midstory would continue self-thinning to 100 stems ha-1, and the overstory would grow to about 10 stems ha-1 in all dbh classes. South. J. Appl. For. 20(2):90-93.

Stochastic Frontier Estimation and Sources of Technical Efficiency in Southern Timber Harvesting

Abstract This research provides estimates of average industry and firm-specific technical efficiency using an econometric stochastic frontier production function for individual firms operating in the southern U.S. pulpwood harvesting industry in both 1979 and 1987. The stochastic frontier production function is capable of distinguishing deviations from the frontier due to uncontrollable stochastic elements, as well as provide a pure measure of technical efficiency. Results indicate that mean industry technical efficiency was nearly constant at 60% in both periods while frontier technical change averaged 1.8% annually over the period. Elements of human capital, technology, and production scale were influential in explaining efficiency differentials among firms. However, the relative influence of these factors changed over time. For. Sci. 41(3):576-593.

Productivity and Cost Changes in Southern Pulpwood Harvesting, 1979 to 1987

Abstract Analyses of southern pine pulpwood harvesting systems indicate that substantial increases in productivity and decreases in per unit costs occurred from 1979 to 1987. Average shortwood harvesting production increased from 34 cords per week in 1979 to 42 cords per week in 1987; average longwood system productivity increased from 191 cords per week in 1979 to 227 cords per week in 1987. Estimated shortwood average costs were $45.50 per cord in 1979 and increased to $48.90 per cord in constant 1988 (real) dollars. Average real longwood harvesting costs decreased from $34.00 per cord in 1979 to $26.50 per cord in 1987. Most productivity improvements and average cost declines overall were attributable to increased use of longwood harvesting systems. South. J. Appl. For. 18(2):83-90.

Technical efficiency and industry evolution in southern U.S. pulpwood harvesting

This research measures technical efficiency among methods of pulpwood harvesting in the southern United States in 1979 and 1987. An econometric frontier production function is modeled using analysis of covariance methods, which results in consistent estimates of method effects. Employed efficiency measures isolate economies of scale from what can be termed pure technical efficiency. Harvesting methods utilizing either extremely low or high capitalization levels were the most technically efficient. Longwood grapple skidder systems were the most efficient, and intermediate systems least efficient. This suggests a noncontinuous improvement in harvesting technology that has investment implications for small producers interested in upgrading low capitalization systems. Scale economies represented only a small percentage of the total efficiency effect, the rest being attributed to efficiency of method. Thus, too much emphasis may be placed on the impacts of scale economies when analyzing structural change in the industry. Efficiency measures correlate well with the observed evolution of the industry over the period and conform with the predictions of economic theory.

North American Aspen: Timber Supply, Utilization, and Research

Abstract Bigtooth and quaking aspen are the two most important white poplar species in North America, comprising 11.9 million ac in the Lake States, 4.4 million ac in western United States, and an estimated 100 million ac in Canada. Lake States aspen utilization increased greatly in the last 10 years and during the period 1982-87 accounted for 47-55% of the total pulpwood harvest. In 1987, removals were estimated at 286 million ft ft³ and growth at 282 million ft³ Canadian aspen utilization has also increased dramatically since 1980 and is expected to expand as demand for structural flakeboard and hardwood pulp increases. Even with increased use, less than 10% of the Canadian allowable cut is being utilized. Despite evidence on the importance of aspen on the economy of the U.S. Lake States and Canada, only a minor amount of research has been undertaken in the last 10 years to genetically improve and/or maintain the existing aspen resource. North. J. Appl. For. 7:168-171, December 1990.