Treesearch

Dendroecology is the science that dates tree rings to their exact calendar year of formation to study processes that influence forest ecology (e.g., Speer 2010 [1], Amoroso et al., 2017 [2]). Reconstruction of past fire regimes is a core application of dendroecology, linking fire history to population dynamics and climate effects on tree growth and survivorship. Since the early 20th century when dendrochronologists recognized that tree rings retained fire scars (e.g., Figure 1), and hence a record of past fires, they have conducted studies worldwide to reconstruct [2] the historical range...

Nature conservation constitutes an important realm of professional practice with strong connections to the discourses on nature and sustainability. In recent decades much of that discourse has taken an explicitly spatial turn, observable across numerous domains of ecological, social, and political thought (Williams et al., 2013; Wu, 2006). The aim of this chapter is to examine how spacing nature conservation, as a form of place-making, is transforming utilitarian natural resource management away from its formative roots in mid-nineteenth-century Newtonian and mechanistic explanations of...

BACKGROUND: Semiochemicals formonitoring, attracting or repelling pest and beneficial organisms are increasingly deployed in agricultural and forest systems for pest management. However, the use of aggregation pheromones and host-plant attractants for the express purpose of increasing the efficacy of classical biological control agents of weeds has not been widely reported. Therefore, we conducted field-based assays to determine if a specialized wax-basedmatrix impregnated with an aggregation pheromone of the northern tamarisk beetle Diorhabda carinulata (Desbrochers) or host-plant...

Forests and grasslands have changed during the past 200 years in the eastern USA, and it is now possible to quantify loss and conversion of vegetation cover at regional scales. We quantified historical (ca. 1786-1908) and current land cover and determined long-term ecosystem change to either land use or closed forests in eight states of the Great Lakes and Midwest. Historically, the region was 35% grasslands (31 million hectares), 38% open forests of savannas and woodlands (33 million hectares), and 25% closed forests (22 million hectares). Currently, the region is about 85% land use (76...

This article presents a test method that was developed to screen adhesive formulations for finger-jointed lumber. The goal was to develop a small-scale test that could be used to predict whether an adhesive would pass a full-scale ASTM E119 wall assembly test. The method involved loading a 38-mm square finger-jointed sample in a four-point bending test inside of an oven with a target sample temperature of 204°C. The deformation (creep) was examined as a function of time. It was found that samples fingerjointed with melamine formaldehyde and phenol resorcinol formaldehyde adhesives had the...

Biofuel properties can be improved through torrefaction, whereby the biomass is treated with moderately elevated temperatures (200–300°C) under conditions that are essentially anaerobic and at atmospheric pressure. Varying the torrefaction conditions of temperature and treatment duration, as well as any feedstock pretreatments (drying, grinding), can generate products having varying degrees of thermal degradation, thus impacting performance in subsequent biofuel applications (e.g., gasifcation, pyrolysis, combustion). Pulp-grade pine wood chips were processed through a laboratory-scale...

Increasing the population of spring Chinook salmon and summer steelhead in Washington state’s Methow River is a goal of the Upper Columbia Spring Chinook Salmon and Steelhead Recovery Plan. Spring Chinook salmon and summer steelhead are listed as endangered and threatened, respectively, under the Endangered Species Act. Installing logjams and reconnecting the river to its floodplain are management actions being undertaken to restore salmon habitat. However, researchers with the U.S. Forest Service Pacific Northwest Research Station, the U.S. Geological Survey, and Idaho State University...

Japanese barberry (Berberis thunbergii), a member of the barberry family (Berberidaceae), is a low-growing perennial shrub. This ornamental shrub was sent to Boston from Russia in 1875 as a substitute for common barberry, a nuisance plant that harbors black stem rust (Puccinia graminis), which affects several cereal crops (Kaufman and Kaufman 2007). Japanese barberry has low wildlife value and deer may promote its spread by creating soil disturbance that favor its growth. It can grow in sun or shade. Due to its shade tolerance, this species is of particular concern within forested areas....

Managers use restorative fire and thinning for ecological benefits and to convert fuel-heavy forests to fuel-lean landscapes that lessen the threat of stand-replacing wildfire. In this study, we evaluated the long-term impact of thinning and prescribed fire on soil biochemistry and the mycorrhizal fungi associated with ponderosa pine (Pinus ponderosa). Study sites were located in the Blue Mountains of northeastern Oregon where prescribed fire treatments implemented in 1998 and thinning treatments in 2000 included prescribed fire, mechanical thinning of forested areas, a combination of...

The pine bark adelgid, Pineus strobi (Hartig, 1839) (Hempitera: Adelgidae), is native to eastern North America and is found throughout the natural range of its main host species, eastern white pine, Pinus strobus L. (Pinaceae), which stretches from the Atlantic coast, west to Ontario and Minnesota (Drooz 1985). For the first time, we confirmed the presence of P. strobi west of this range in Washington, Colorado, and Saskatchewan by identification of contemporary samples using morphology and DNA barcodes. We also include information from existing slide-mounted specimens of P. strobi...