Treesearch

The ability to detect diseased trees before symptoms emerge is key in forest health management because it allows for more timely and targeted intervention. The objective of this study was to develop an in-field approach for early and rapid detection of beech leaf disease (BLD), an emerging disease of American beech trees, based on supervised classification models of leaf near-infrared (NIR) spectral profiles. To validate the effectiveness of the method we also utilized a qPCR-based protocol for the quantification of the newly identified foliar nematode identified as the putative causal...

Fine roots serve as the primary interface between trees and the soil, and they are dynamic in their response to environmental conditions. Among many functions, they are principle in gathering nutrients and water, and they constitute a major component of the tree. Their overall contribution to soil carbon flux is not well understood, nor is the effect of site and genotype on their dynamics, and these factors are crucial to understanding nutrient cycles and tree growth under variable conditions. This study evaluated how the fine root dynamics of loblolly pine (Pinus taeda L.) might be...

Wildfires are increasingly understood as an ecological driver within the entire Arctic biome. Arctic soils naturally store large quantities of C, as peat has formed throughout the Holocene. For the Siberian Arctic, we used observations from the MODIS remote sensing instrument to document changes in frequency, geographic extent, and seasonal timing of wildfires as well as vegetation productivity (GPP, NPP, EVI).We also used correlation and regression analysis to identify environmental factors of temperature, precipitation, and lightning occurrence associated with these changes. For the...

There is little doubt that changes in climate will affect wildlands, wildland fire, and suppression of fire (Abatzoglou and Kolden 2013, Abt et al. 2009, Flannigan et al. 2005, Flannigan et al. 2006, Flannigan et al. 2016, Littell et al. 2009, Littell at al. 2016, Liu et al. 2014, McKenzie et al. 2016, Mitchell et al. 2014, Prestemon et al. 2009, Riley et al. 2019, Westerling et al. 2006). Direct increases in area burned and numbers of large fires, resulting from more days with extreme fire weather, longer periods of sequential days with extreme fire weather, and longer fire seasons in...

There has been a significant increase in the use of wood pellets for energy in the past decade due in large part to their climate mitigation potential. Because of this, the demand for wood pellets is largely driven by policy, as well as socioeconomic development, making projections of future wood energy markets highly uncertain. The aim of this study is to provide projections of future wood energy market trends under five distinct socioeconomic scenarios based on the assumed future evolution of gross domestic product, population, technological change, trade openness, and bioenergy preferenc...

In the United States, the forest products industry loses an estimated $500 million to $1 billion annually to illegal logging. Once illegally harvested wood is removed from the forest, it’s difficult for USDA Forest Service law enforcement to prove beyond a reasonable doubt that the wood was illegally harvested. The use of DNA is a recent development that can help law enforcement determine if wood is illegally sourced. Researchers Rich Cronn and Laura Hauck with the Forest Service’s Pacific Northwest Research Station developed DNA forensic protocols to evaluate bigleaf maple wood products...

Fire has both positive and negative effects on insects. Bark beetle and defoliator epidemics have positive and negative effects on wildfires. Additional study of these relationships is warranted given the effects of climate change on forests and forest disturbances, recent declines in some pollinator species in North America, and interests in restoring fire-adapted forest ecosystems.

The National Agricultural Statistics Service, the statistical arm of the US Department of Agriculture, and the Multi-Resolution Land Characteristics Consortium, a group of the US federal agencies, collect and publish several land-use and land-cover data sets. The aim of this study is to analyze the consistency of forestland estimates based on two widely used, publicly available products: the National Land-Cover Database (NLCD) and Cropland Data Layer (CDL). Both remote sensing based products provide raster-formatted land-cover categorization at a spatial resolution of 30 m. Although the...

Emerald ash borer (EAB), Agrilus planipennis (Coleoptera: Buprestidae), was first detected infesting ash (Fraxinus spp.) trees in southeastern Michigan and nearby Ontario in 2002. Shortly after the discovery of EAB in North America, researchers began foreign exploration for natural enemies of this destructive beetle in northeastern Asia, where it is native. This activity led to development of a classical biological control program in 2003. In 2007, North American regulatory agencies approved the first environmental releases of three EAB hymenopteran parasitoid species from China to...

Sustainable management of forest ecosystems requires the use of reliable and easy to implement biodiversity and naturalness indicators. Tree-relatedmicrohabitats (TreMs) can fulfill these roles as they harbor specialized species that directly or indirectly depend on them, and are generally more abundant and diverse in natural forests or forests unmanaged for several decades. The TreM concept is however still recent, implying the existence of many knowledge gaps that can challenge its robustness and applicability. To evaluate the current state of knowledge on TreMs, we conducted a systematic...