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Copyright of Canadian Journal of Forest Research is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Interest in the use of forest-derived biomass for energy has prompted comparisons to fossil fuels and led to controversy over the atmospheric consequences of its utilization. Much of the debate has centered on the carbon storage implications of utilizing whole trees for energy and the time frame necessary to offset the carbon emissions associated with fixed-life bioenergy facilities. Forest harvest residues may provide a cost-effective, carbon friendly alternative; however, robust empirical estimates of the carbon consequences of utilizing this feedstock are needed to inform policy and management related to forest-based bioenergy. This study used a modeling approach to assess the availability of harvest residues in northern Minnesota and compared the estimated carbon emissions from in-forest decomposition with emissions from processing, transport, and utilization of residues in a proposed 26 MW bioenergy facility. Model results suggest that the combined emissions from the proposed facility would be 42 percent greater – a net difference of 2,888,751 Mg of CO2 – than in-forest decomposition emissions over a 25-year period. The disparity in carbon emissions with and without the proposed facility decreases with increasing time, ultimately reducing to solely emissions from harvesting and transport 190+ years after establishment. These findings have important implications for the development of renewable energy standards including incentives aimed at increasing the use of forest-derived biomass. [Copyright &y& Elsevier]

There is great potential for the production of woody biomass feedstocks from hybrid aspen stands; however, little is known about the response of these systems to silvicultural treatments, such as shearing. We sought to address this need by integrating results from more than 20 years of individual tree and yield measurements in hybrid aspen (Populus tremuloides Mich. × P. tremula L.) stands in north central Minnesota. Specifically, tree and stand-level responses are described in terms of sucker density, early diameter and height characteristics, volume, and biomass production. Overall, shearing treatments increased the density of hybrid aspen stems, relative to preshear densities at the same age. In addition, average stem diameter and volume as well as stand-level biomass were considerably greater in hybrid aspen stands relative to similarly aged native aspen stands also established via shearing treatment. These findings illustrate that coppice systems using hybrid aspen provide great potential to rapidly produce biomass feedstocks, with little management investment. [ABSTRACT FROM AUTHOR]

• We propose a data assimilation procedure for updating estimates with USFS FIA data. • This procedure incorporates the design-based and model-based inferences. • Updated estimates are comparable with estimates requiring 5+ years pooled FIA data. • This procedure is 100% compatible with the FIA database that is publicly available. • This procedure is unbiased and efficient, suitable for official reporting instruments. The United Nations Framework Convention on Climate Change requires annual estimates for forestry and ecological indicators to monitor the change in forest resources, the sustainability of forest management, and the emission and sink of forest carbon. It is particularly important to update estimates of forestland area in a timely fashion and at flexible geographical scales, not only for its value in monitoring biological diversity at the ecosystem scale, but also because of its close association with other indicators such as forest biomass and carbon. However, in the US, the Forest Survey Handbook advises that the sampling error should not exceed 3% per 404686 ha (one million acres) of forestland area, a demanding standard barely met by pooling the Forest Inventory and Analysis (FIA) panel data measured in an inventory cycle of 5–10 years. Consequently, this study aims to propose and illustrate an updating procedure using data assimilation that integrates a design-based estimator with a model-based mixed estimator for updating annual estimates at two population levels, the state- and county-levels. The three states in the USA, Minnesota (MN), Georgia (GA) and California (CA), representing the Northern, the Southern and the Pacific Northwest FIA programs, constitute the study areas. FIA data collected were based on a 5-year inventory cycle for MN (2006–2010) and GA (2005–2009), and a 10-year cycle for CA (2001–2010). The total number of sample plots was 17764 for MN, 6323 for GA, and 16740 for CA. Distinguishing features attribute to this procedure include: (1) unbiasedness: the integration of design-based estimates into the mixed estimator introduces a favorable property – unbiasedness, which could be the property national forest inventories concern the most; (2) efficiency: considerable improvements in estimation precision greater than 55%, achieving sampling errors as small as those relying on using 5–10 years pooled FIA data; (3) time: compared with the temporal trends reflected by design-based estimates, the updated trends were of much smoother trend lines and narrower confidence intervals that would better depict temporal changes for a population at flexible spatial scales; (4) space: this procedure is scale-invariant, meaning its efficiency is not affected by an inventory employing either a large- or small-area estimation, which was demonstrated at the two population levels; and (5) generalizability: this procedure is unbiased and efficient, 100% compatible with the FIA database which is readily available to the public, and thus suitable for various official reporting instruments. [ABSTRACT FROM AUTHOR]

With shrinking budgets, staff reductions, and increased availability and access to digital technologies, Extension educators will be seeking ways to convert face-to-face programs to alternate formats. When converting Minnesota's biomass harvesting guidelines for online delivery, we learned many lessons while planning, developing, and testing our curriculum that can help others through a similar process. [ABSTRACT FROM AUTHOR]

Disturbances play a critical role in forest ecosystem dynamics. Disturbances cause changes in forest structure which in turn influence the species composition of the site and alter landscape patterns over time. The impacts of disturbance are seen over a broad spectrum of spatial scales and varying intensities, ranging from biotic agents such as insect and leaf disease outbreaks to abiotic agents such as a windstorm (a stand-replacing disturbance). This study utilized Forest Inventory and Analysis (FIA) data collected between 1999 and 2014 in the US Lake States (Michigan, Minnesota, and Wisconsin) to examine the impacts that disturbances have on the growth of residual trees using species-specific diameter increment equations. Results showed that animal and weather damage were the most common disturbance agents and fires were the least common in the region. Results also indicated that while the diameter increment equations performed well on average (overprediction of 0.08 ± 1.98 cm/10 years in non-disturbed stands), when the data were analyzed by species and disturbance agent, the model equation was rarely validated using equivalence tests (underprediction of 0.30 ± 2.24 cm/10 years in non-disturbed stands). This study highlights the importance of monitoring forest disturbances for their impacts on forest growth and yield.