Treesearch

In 2010, there were 417 active primary wood-using mills in Minnesota. These mills processed 238.8 million cubic feet of industrial roundwood. There was 226.1 million cubic feet of industrial roundwood harvested from Minnesota forests. The majority of roundwood harvested was pulpwood, accounting for 61 percent of the total. The harvesting of industrial roundwood products generated 110.6 million cubic feet of harvest residues. Primary wood-processing mills generated 1.5 million green tons of mill residues.

Increased popularity of recreational activities in natural areas has led to the need to better understand their impacts on wildlife. The majority of research conducted to date has focused on behavioral effects from individual recreations, thus there is a limited understanding of the potential for population-level or cumulative effects. Brown bears (Ursus arctos) are the focus of a growing wildlife viewing industry and are found in habitats frequented by recreationists. Managers face difficult decisions in balancing recreational opportunities with habitat protection for wildlife. Here, we...

Realizing the benefits of tree planting programs depends on tree survival. Projections of urban forest ecosystem services and cost-benefit analyses are sensitive to assumptions about tree mortality rates. Long-term mortality data are needed to improve the accuracy of these models and optimize the public investment in tree planting. With more accurate population projections, urban forest managers can also plan for cycles of tree planting, death, removal, and replacement to achieve canopy cover goals. Analytical tools from demography, such as life tables and mortality curves, could be used...

Insects are among the world's most ecologically and economically important invasive species. Here we assemble inventories of native and nonnative species from 20 world regions and contrast relative numbers among these species assemblages. Multivariate ordination indicates that the distribution of species among insect orders is completely different between native and non-native assemblages. Some orders, such as the Psocoptera, Dictyoptera, Siphonaptera, Thysanoptera, and Hemiptera, are always over-represented in the non-native compared to native assemblages. Other orders, such as the...

Biogeochemical cycles are inherently linked through the stoichiometric demands of the organisms that cycle the elements. Landscape disturbance can alter element availability and thus the rates of biogeochemical cycling. Nitrification is a fundamental biogeochemical process positively related to plant productivity and nitrogen loss from soils to aquatic systems, and the rate of nitrification is sensitive to both carbon and nitrogen availability. Yet how these controls influence nitrification rates at the landscape scale is not fully elucidated. We, therefore, sampled ten watersheds with...

Prescribed fire is increasingly being viewed as a valuable tool for mitigating the ecological consequences of long-term fire suppression within fire-adapted forest ecosystems. While the use of burning treatments in northern temperate conifer forests has at times received considerable attention, the long-term (>10 years) effects on forest structure and development have not been quantified. We describe the persistence of prescribed fire effects in a mature red pine (Pinus resinosa Ait.)-dominated forest in northern Minnesota, USA over a ∼50 year period, as well as the relative roles of fire...

Thinning is a well understood concept used to manage density dependent factors at the stand level. This study evaluates the effect of planting density, cultural intensity, and thinning treatment on loblolly pine post-thinning individual tree development. The Lower Coastal Plain Culture/Density Study, has four initial densities, in combination with two cultural treatments, that were thinned at age 12 to the current density on the lowest initial density. Analysis of data six years post-thin for the Lower Coastal Plain focuses on the effects of cultural intensity and density regime effects...

Pine stand density is a key determinant of damage resulting from attacks by the southern pine beetle (SPB, Dendroctonus frontalis Zimm.). High-density stands of maturing loblolly pine (Pinus taeda L.) are at high risk for losses to SPB, and reducing stand density is the primary tool available to forest managers for preventing and mitigating damage. Field studies are expensive and inflexible for evaluating various stand treatments over large areas and long time periods, especially with unpredictable SPB population levels. To address these shortcomings, and to provide guidance on silvicultura...

Recent advances in somatic embryogenesis permit large numbers of clonal loblolly pine (Pinus taeda L.) to be produced and deployed. Clones may have greater growth (mean annual increment exceeding 30 cubic meters per hectare per year), greater stand uniformity and may be more susceptible to genotype by environment interactions when they are deployed in intensively managed plantations. Consequently, large numbers of clones will need testing under a range of silvicultural treatments to effectively and efficiently identify those that are best for deployment. Crown ideotypes are described by...