Treesearch

Background. Experiencing an adequate amount of cold temperatures over winter is necessary for many temperate tree species to break dormancy and flower in spring. Thus, changes in winter and spring temperatures associated with climate change may influence when trees break dormancy and flower in the future. There have been several experimental studies that have quantified the effectiveness of cold temperatures for chilling requirements for vegetative budburst of temperate trees; however, there are few experimental studies addressing the chilling requirements for reproductive budburst of...

Forest landscape simulation models (FLSMs) – often used to understand and project forest dynamics over space and time in response to environmental disturbance – have rarely included realistic epidemiological processes of plant disease transmission and impacts. Landscape epidemiological models, by contrast, frequently treat forest ecosystems as static or make simple assumptions regarding ecosystem change following disease. Here we present the Base Epidemiological Disturbance Agent (EDA) extension that allows users of the LANDIS-II FLSM to simulate forest pathogen spread and host mortality...

Sampling methods in natural resources are largely based on probability proportional to size or frequency concepts and are often referred to as areal sampling methods, because they induce an enlarged area about the object within which a random point may fall and select the object. The ability to compare di erent sampling methods is key to designing inventories and assessing the eciency of newly developed methods when compared against existing methods. Simulation methods are often used on synthetic populations of individuals with the desired characteristics of some target population in...

This paper reports on the ground-contact durability of lesser-used wood species of the northeastern United States after treatment with copper-based preservatives. Stakes (19 x 19 x 457 mm) cut from balsam-fir (Abies balsamea), eastern hemlock (Tsuga canadensis), eastern spruce (mixture of Picea glauca, Picea mariana and Picea rubens), red maple (Acer rubrum) or eastern white pine (Pinus strobus) were treated with one of four concentrations of chromated copper arsenate type C (CCA-C), copper citrate (CC), alkaline copper quat type C (ACQ-C) or copper azole type A (CBA-A) and placed into the...

Impact of planetary ball milling on pre-milled wood fiber was studied to improve efficiency of energy consumption for bioconversion using post-harvest forest residuals. Crystalline cellulose decreased from 40.73% to 11.70% by ball milling. Crystallinity index of ball milled wood samples had a negative correlation with glucose yield (r=−0.97, p < .01), xylose/mannose (r=−0.96, p < .01), and a positive correlation with median particle size (r=0.77, p < .01). Range of glucose yield and xylose/mannose yield for ball milled samples was found to be 24.45–59.67% and from 11.92% to 23.82%,...

To accelerate development of new and improved wood adhesives for engineered wood products, the optimal adhesive penetration into wood needs to be better understood for specific products and applications. Adhesive penetration includes both flow of adhesives into wood micron-scale voids and infiltration into the polymer components of the wood cell wall layers. In this work, X-ray computed tomography (XCT) and X-ray fluorescence microscopy (XFM) were used to study adhesive flow and infiltration. Model wood–adhesive bondlines were made using loblolly pine(Pinus taeda)latewood substrates and...

Roads affect flora and fauna across the world. Large mammals are particularly vulnerable to road effects because their large home ranges lead to a higher probability of contact with road networks. Disturbance associated with roads can alter the probability of habitat use by making suitable habitat near roads inaccessible or underused. Many studies and monitoring programs for large mammals such as guanaco (Lama guanicoe) in South America, however, rely on counts made from roads to estimate population abundance and distribution. These counts implicitly assume that animal responses to roads...

The use of mass timber structural products in tall building applications (6–20 stories) is becoming more common around the world including North America. A potential concern is the environmental wetting of mass timber products during construction because such products may dry out more slowly than light-frame structural lumber, and wood, as an organic material, is susceptible to deterioration at elevated moisture contents. In order to better understand the moisture conditions present in high rise timber constructions, a long-term moisture monitoring program was implemented on an eight...

In their recent article in Ecology and Evolution, O’Loughlin and Green (2017) set out to (1) redefine the term secondary invasion as the condition "when invader success is contingent on other invaders altering the properties of recipient ecosystems" and (2) propose a framework for accounting for this phenomenon in invasion ecology. We applaud the second objective. However, redefining the term secondary invasion in the very narrow manner they propose is problematic and unfounded. Here, we establish that secondary invasion represents a broad range of phenomena that encompasses invader-facilit...

Biological invasions present a global problem underlain by an ecological paradox that thwarts explanation: how do some exotic species, evolutionarily naïve to their new environments, outperform locally adapted natives? We propose that community assembly theory provides a framework for addressing this question. Local community assembly rules can be defined by evaluating how native species’ traits interact with community filters to affect species abundance. Evaluation of exotic species against this benchmark indicates that exotics that follow assembly rules behave like natives, while those...