Treesearch

Glue laminated timber (glulam) is an engineered wood product composed of wood laminations bonded together with durable adhesives. Glulam is versatile ranging from simple, straight beams to complex, curved structural members and are used in a variety of applications including residential and commercial construction where they are often exposed due to the timeless aesthetic of wood. Glulam beams are also resource-efficient and offer designers highly predictable structural and fire performance when used in accordance with design specifications. However, factory-cut or field modifications to...

Timber structures decay over time with degradation in their structural integrity. Changing environmental conditions, varying loads, exposure to moisture or insect attacks lead to changes in their vibrational response behaviour. Here we present a low-cost device used as a triggered exciter to enable the monitoring of the structural integrity of timber bearers or even power poles in electricity networks. The actuation is initiated by a novel purpose-built, calibrated spring-loaded piezo-electric exciter. The device is connected to a fibre-optical network with optical accelerometers to...

Sulfurized polyacrylonitrile (SPAN) is a promising cathode active material capable of suppressing lithium polysulfide dissolution in lithium−sulfur (Li−S) batteries. However, due to the low S content in SPAN, achieving a high SPAN areal loading without compromising specific capacity and cycling stability would be required. To address this challenge, we took advantage of the inherent porous structure of natural wood and engineered carbonized delignifed wood (CDW) frameworks using a delignification/low-temperature pyrolysis approach. The unique design of the SPAN-impregnated CDW (SPAN@CDW)...

As populations in developing areas continue to increase in recent years, urban and community forestry (U&CF) has received considerable attention due to the ecological, social, and economic significance of trees and green landscapes in urban and semi-urban settings. Based on a regional survey of private, public, and nonprofit businesses and agencies involved in U&CF, we first developed a complete profile of the U&CF sector in the southern United States (SUS) and then estimated the economic contribution of U&CF businesses and activities to the thirteen-state regional economy. We estimated...

Candidate insecticide products under consideration for use as soil termiticides are required to have specific efficacy data for federal registration by the U.S. Environmental Protection Agency (EPA). Data that are collected annually by the U.S. Department of Agriculture (USDA) Forest Service (FS) Forest Products Laboratory (FPL), Durability and Wood Protection research work unit (RWU 4723), serve to fulfill this need. The FS group installs and evaluates wooden test pieces on plots of soil treated with candidate termiticide products. Data from these studies are used in the registration...

Currently, the North American standard, ANSI/APA PRG 320: Standard for Performance-Rated Cross-Laminated Timber, requires a full-scale compartment fire test to qualify adhesives for use in cross laminated timber (CLT) for structural applications. This test is necessary to determine whether the adhesives will experience heat delamination - a premature adhesive failure during fire that can lead to sudden fire regrowth during the decay phase of a fire commonly referred to as a secondary flashover. The required full-scale test is cost-prohibitive to adhesive manufacturers when developing new...

Forest managers historically sought locally sourced seed for planting to ensure that future forests were adapted to local conditions. As the climate warms, managers are increasingly seeking seed from more southerly locales. This movement of seed from outside the local seed zone, known as assisted migration, is one of several silvicultural tools being enacted to improve the resilience and adaptation of forests in the future (Williams and Dumroese 2016). A variety of strategies to implement assisted migration have been proposed (Breed et al. 2013, Havens et al. 2015, Potter and Hargrove...

Assisted migration is a promising silvicultural tool that could promote the sustainability of forest ecosystems and ecological services in the context of climate change. Assisted migration plantations, however, could be at a high risk of failure when mammalian herbivores (e.g., deer and hares) are abundant. Here, we developed an approach based on chemical content to predict the susceptibility to browsing of translocated seedlings. First, we determined which chemical compounds would be appropriate proxies of susceptibility. Second, we analyzed the chemical content of eight North American...

Quercus rubra L. is a hardwood species found throughout the eastern United States. Although climate change is projected to increase this species' suitable habitat range, current population structures and migration patterns may not be suitable to sustain future forest health. To investigate how populations respond when planted outside of their traditional ranges, we collected seeds from 22 Q. rubra populations spanning the species range and planted them in two common garden sites. Ford forest (cooler and drier) and Kellogg Forest (warmer and wetter) sites are located in Michigan's upper and...

Apostle Islands National Lakeshore (APIS) is one of the few archipelagos in Lake Superior, the largest freshwater body in the world. Sandstones deposited about 600 million years ago form the foundation for several rare features such as clay bluffs, rock ledges, coastal wetlands, and sandscapes (sandspits, cuspate forelands, tombolos). A double tombolo on Stockton Island supports a globally critically imperiled Great Lakes Barrens feature. Rare communities include boreal, krummholz, and old growth forests that support eastern hemlock, yellow birch, northern white-cedar, and Canada yew, a...