Treesearch

Eastern red cedar (ERC) is an abundant natural resource in the U.S. and has been investigated for the extraction of cedarwood oil (CWO) and CWO bioactivity, particularly its use to protect wood against termites and decay fungi. Methanol extraction of ERC sawdust gives a burgundy-colored oil (BO) that is comprised of both CWO and a burgundy solid (BS). The BO was significantly more inhibitory against two species of white-rot decay fungi than CWO alone, suggesting the BS itself might have inhibitory bioactivity. This study investigated the wood preservation properties of the BS alone, in...

Life cycle assessment (LCA) has been used to understand the carbon and energy implications of manufacturing and using cross-laminated timber (CLT), an emerging and sustainable alternative to concrete and steel. However, previous LCAs of CLT are static analyses without considering the complex interactions between the CLT manufacturing and forest systems, which are dynamic and largely affected by the variations in forest management, CLT manufacturing, and end-of-life options. This study fills this gap by developing a dynamic life-cycle modeling framework for a cradle-to-grave CLT manufacturin...

The research presented in this research note was conducted to examine the potential to use lodgepole pine boards in laminated roof decking. A sample of visually graded lodgepole pine boards was obtained and evaluated. Modulus of elasticity (MOE), moisture content, specific gravity, and visual grade of each specimen were determined. Three-ply laminates were then prepared from the sample boards. Four types of laminates were prepared, based on either the visual grade or MOE of the boards used. Because bending MOE and strength are important mechanical properties for wood products in roof deck...

Mass timber, which includes cross laminated timber, is becoming increasingly popular as a material choice for mid-level and high-rise construction. Material durability, especially in extreme exterior exposures, is a key concern of developers that has to date not been fully resolved. Data on the effectiveness of currently labeled soil termiticides, as well as spray-on borates applied either post-construction or as a remedial treatment, needs to be generated for cross laminated timber (CLT) structures. Current design standards do allow for preservative treated and naturally durable wood but...

Tannic acid (TA) is a bio-based high-molecular-weight organic molecule. Although biologically sourced, TA is a pollutant in industrial wastewater streams, and there is desire to find applications in which to downcycle this molecule. Many flame retardants (FRs) used in epoxy are synthesized from petroleum-based monomers. Various bio-based modifiers have been developed, but increasing the flame retardancy of the system without trade-offs with other properties has proved challenging. In this work, TA is incorporated into the thermoset. The molecular behavior of the system was dependent on...

Copper tolerance of brown-rot basidiomycete decay fungi can lessen the efficacy of copper-containing wood preservatives for wood products in-service. The purpose of this study was to evaluate wood mass loss and differential expression of three genes that have putative annotations for copper-transporting ATPase pumps (FIBRA_00974, FIBRA_04716, and FIBRA_01430). Untreated southern pine (SP) and SP treated with three concentrations of ammoniacal copper citrate (CC, 0.6, 1.2, and 2.4%) were exposed to two copper-tolerant Fibroporia radiculosa isolates (FP-90848-T and L-9414-SP) and copper-sens...

Chinese privet (Ligustrum sinense) is one of the most problematic invasive plants in many parts of the world where it often dominates the shrub layer in riparian forests. We aimed to evaluate the role of privet invasion on litter inputs, rates of litter decomposition and litter-dwelling arthropods in the Southeastern United States. To do this we: (1) evaluated the relative contribution of privet to total litter-fall, (2) compared breakdown of artificial leaves (filter paper) in plots which had or had not been subjected to experimental privet removal, and (3) compared litter breakdown and...

In order for sustainable nanomaterials such as cellulose nanocrystals (CNCs) to be utilized in industrial applications, a large-scale production capacity for CNCs must exist. Currently the only CNCs available commercially in kilogram scale are obtained from wood pulp (W-CNCs). Scaling the production capacity of W-CNCs isolation has led to their use in broader applications and captured the interest of researchers, industries and governments alike. Another source of CNCs with potential for commercial scale production are tunicates, a species of marine animal. Tunicate derived CNCs (T-CNCs)...

In mid-September 2020, millions of hectares in the western U.S. were on fire and the year’s second wave of seasonal hurricanes and tropical storms were queueing up to batter the states along the Gulf of Mexico. As members of a National Academies of Sciences, Engineering, and Medicine committee tasked with assessing the need for and supply of native seed in the Western United States and other regions of the country, we viewed the unfolding natural disasters as an appropriate, if troubling, backdrop for our work. The assessment of the seed supply was requested by the U.S. Bureau of Land...

Root disease pathogens, including Armillaria, are a leading cause of growth loss and tree mortality in forest ecosystems of North America. Armillaria spp. have a wide host range and can cause significant reductions in tree growth that may lead to mortality. DNA sequence comparisons and phylogenetic studies have allowed a better understanding of Armillaria spp. taxonomic diversity. Genetic sequencing has facilitated the mapping of species distributions and host associations, providing insights into Armillaria ecology. These studies can help to inform forest management and are essential in...