Treesearch

Temperate forests play an important role in the sequestration and storage of carbon. We evaluated the long-term effects of manipulating stand density on aboveground live tree carbon dynamics and volume production for separate pine (Pinus spp.) and oak (Quercus spp.) forests of central USA. For both species groups, stand-level carbon storage in standing live trees was greatest without management, with unthinned pine plateauing around 100 Mg/ha of carbon at approximately 50 years old and the oak stands increasing to around 100 Mg/ha of carbon by about 80 years old. In the pine stands,...

The long-term effects of soil acidification on the development of a young aggrading Appalachian forest were examined after 21 years of continuous treatment. Beginning with a clearcut harvest in 1997, annual ammonium sulfate (N+S) and ammonium sulfate with lime (N+S+LIME) treatments were aerially applied to a developing forest. The lime treatment was designed to counteract the acidification of the nitrogen and sulfur amendments. After 21 years, the N+S and N+S+LIME treatments had little impact on total woody biomass accumulation relative to the control. There were significant differences...

Understanding soil organic matter (SOM) formation as a balance between soil microbial access to organic plant inputs and protection by chemical recalcitrance and mineral associations can greatly improve our projections of this important terrestrial carbon pool. However, gaps remain in our understanding of the processes controlling the formation and destabilization of SOM and how these processes are affected by persistent global changes, such as nitrogen (N) deposition. To assess how elevated N deposition influences decomposition dynamics and the fate of plant inputs in a temperate deciduous...

Understanding the forest carbon cycle has become increasingly important as carbon dioxide (CO2) emissions contribute to the changing climate. Decomposition is a major component of the forest carbon cycle; however, aspects of wood decomposition remain poorly understood, especially for stumps. To fill this knowledge gap, we examined the change in CO2 emissions over time from Picea rubens Sarg. (red spruce) stumps using a 32-year chronosequence (i.e., 0, 2, 4, 8, 23, and 32 years since harvest) derived from detailed harvesting records in a northern conifer forest in central Maine, USA, that...

We analyzed USDA Forest Service (Forest Service) employment data from 1995 to 2017, by race and ethnicity, gender, as well as race/ethnicity and gender, to assess progress towards the Forest Service’s goal of achieving a multicultural workforce that reflects the US population. We look at the trends by an employee’s level in the Forest Service and by branch of the Forest Service. Our data show an overall decrease in the workforce by 24%, an increase in diversity in Forest Service leadership levels, little change in the percentage of employees in non-White racial/ethnic groups combined, the...

The federally endangered Sonoran pronghorn (Antilocapra americana sonoriensis; herein, pronghorn) is endemic to arid desert landscapes in the southwestern United States (U.S.) and northwestern Mexico. Historically, the range of Sonoran pronghorn in the U.S. extended east from the Salton Sea in California to Tucson and Nogales in Arizona and extended south from the Salton Sea and Phoenix, Arizona, to the border with Mexico (Phelps and Webb 1981, Krausman et al. 2005). Factors that contributed to the decline of pronghorn include habitat fragmentation, livestock grazing, and historical...

Serious games are designed to achieve specific educational or other practical purposes beyond pure entertainment. These games take many different forms—from card decks to massive multiplayer online games—and have proliferated across diverse fields. This note introduces IMPACT: Forestry Edition, a serious board game designed to help forestry professionals and stakeholders think more broadly, critically, and creatively about the future of forestry. We describe the game and feedback from beta testing and discuss the advantages and potential drawbacks of gaming methods. A "print and play"...

Fire managers often make decisions about wildfire incidents on a landscape scale. While several well developed models can predict fire behaviour at these scales, the paucity of data they draw upon can limit their range of validity. Other models explicitly represent the physical complexities of a fire environment, but at increased computational costs and increased sensitivity to boundary conditions. In this paper, we explore a middle ground between landscape level, data-driven fire behaviour predictions and physics-based, computationally expensive models. As a first step, we employ machine...

Spatial modelling and machine learning are powerful techniques that can be used to identify patterns within data and build complex relationships between response and predictor variables. While powerful, many of these techniques are computationally intensive and are not designed to fully leverage high performance computing resources, especially when used within a geospatial context. To fully leverage system resources, while facilitating various spatial, machine-learning, and statistical modelling workflows, we developed a Python-based processing library called raster_tools. The raster_tools...

This fully bilingual revised and expanded edition of the 2011 publication, Identification of Central American Woods, will serve as a field manual for the identification of the common commercial timbers of Central America, Mexico, and the Caribbean. It is intended as a tool for customs inspectors and other officials to control and regulate the flow of timber and wood products into and out of their countries and can be used as an academic reference to train wood anatomists.