Treesearch

We report on the results of a multi-disciplinary project (including wood identification, radiocarbon dating and strontium isotope analysis) focused on a collection of pre-Columbian wooden carvings and human remains from Pitch Lake, Trinidad. While the lake's unusual conditions are conducive to the survival of organic artefacts, they also present particular challenges for analysis. There is a loss of any contextual association beyond that of the lake, and specific methodologies are required to deal with pitch contamination. A surprising taxonomic range of woods was employed for the various...

This paper evaluates the effects of acetylation level and experimental method on the observed fber saturation point (FSP) of loblolly pine (Pinus taeda)woodmeasuredusing differential scanning calorimetry. To achieve this goal, 1-mm-thick latewood samples were tested overawiderange of equilibrium moisture content(EMC). In this work, the FSP was defined as the non-freezable portion of water of the samples.Two experimental methods were used: the extrapolation of the melting enthalpy to zero and the direct calculation of the non-freezable water amount. For both methods, the FSP decreased with...

The taxonomic status of Dendroctonus vitei Wood (Coleoptera: Curculionidae: Scolytinae) and Dendroctonus mexicanus Hopkins is supported by biological and morphological data. However, the differentiation of these species has been extremely difficult because most of the morphological characters have not been well illustrated and some of them are geographically variable. Seminal rod shape has been the only reliable characteristic to identify these species. The main purpose of this study was to look for new morphological characters for the identification of these species as well as to evaluate...

For millennia, forests have been a strategic resource for mankind, providing building material for houses, ships, and mining; household and industrial fuel; hunting grounds and grazing opportunities for cattle. Despite its strategic importance, forest management was often not sustainable. Many European countries have a long history of deforestation and overexploitation of forest resources. North America has also seen substantial deforestation since European colonization. The principles of sustainable forest management were formulated around 1700 by Von Carlowitz in Germany (1713). Centuries...

Ecosystems are under increasing stress from environmental change, including invasion by non-native species that can disrupt ecological processes and functions. Chinese tallow [Triadica sebifera (L.) Small] is a highly invasive tree species in southeastern US forests, prairies, and wetlands, and effectively managing this invasive species is a significant challenge for scientists and land managers. In this review, we synthesize the literature on invasion ecology and management of Chinese tallow. Our review suggests that the invaded range of Chinese tallow is currently limited by dispersal in...

Key message The suite of traits expressed as seedlings by coastal and mountain longleaf pine and south Florida slash pine suggest they can survive fire in the seedling stage. In contrast, loblolly pine and typical slash pine tolerate fire when mature but do not exhibit traits that allow them to survive fire when young, representing a different strategy for survival in frequently burned communities. Context Fire is an important driver in the distribution and abundance of southern US pine species, and seedling fire tolerance often determines individual survival under frequent fire regimes....

Since the mid-19th century, rare prehistoric wooden carvings and human skeletal remains have been dredged from Pitch Lake, Trinidad, during commercial asphalt mining. Establishing a chronology for these objects is challenging, due to both a lack of stratigraphic and contextual information and the necessity to completely remove any pitch to ensure accurate radiocarbon (14C) dates. A range of solvent extraction protocols was tested to identify the most suitable one for pretreating the Pitch Lake artifacts, and then applied to ten wooden objects and a human cranium recovered from the lake....

The production of renewable chemicals and biofuels must be cost- and performance- competitive with petroleumderived equivalents to be widely accepted by markets and society. We propose a biomass conversion strategy that maximizes the conversion of lignocellulosic biomass (up to 80% of the biomass to useful products) into high-value products that can be commercialized, providing the opportunity for successful translation to an economically viable commercial process. Our fractionation method preserves the value of all three primary components: (i) cellulose, which is converted into dissolving...

To keep environmental product declarations current, the underlying life-cycle inventory (LCI) data and subsequent life-cycle assessment data for structural wood products must be updated. Primary data collected from the industry for the year 2012 were analyzed using the weighted-average to update LCIs for laminated veneer lumber (LVL) production on a 1-m3 basis in the Southeast (SE) and Pacific Northwest (PNW) regions of the United States. In addition, cradle-to-gate life-cycle impact assessments (LCIAs) were performed to assess the environmental impacts associated with LVL production for...

Transparency of environmental impacts for building products is of increasing concern. For wood building products, updating life-cycle assessment (LCA) data are critical to ensure that the corresponding environmental product declarations are of the proper recency to maintain this transparency. This study focused on the developing up-to-date life-cycle inventory (LCI) and associated life-cycle impact assessment (LCIA) data for composite I-joist production in the Southeast (SE) and Pacific Northwest (PNW) regions of the United States. Components of the I-joist production system included in...