Treesearch

The emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is native to eastern Asia and is primarily a pest of ash (Fraxinus) trees (Fig. 1). Established populations of EAB were first detected in the United States and Canada in 2002 (Haack et al., 2002), and based on a dendrochronology study by Siegert et al. (2009), the original EAB introduction likely occurred in the early to mid-1990s in Michigan. In European Russia, EAB was first found near Moscow in 2003, but not officially identified until 2005 (Izhevskii and Mozolevskaya, 2010). EAB has become a serious...

Surface water quality in the Lower Mississippi River Basin (LMRB) and the adjacent Gulf of Mexico has degraded over the past several decades primarily due to deforestation to agricultural lands and the loss of wetlands. This study investigated the benefits of reforestation upon nitrate–nitrogen (NO-3---N) and orthophosphate (PO3-4) load reductions in the Lower Yazoo River Watershed (LYRW) within the LMRB using the BASINS-HSPF model. The model was calibrated and validated with available experimental data prior to its applications. Two simulation scenarios were then performed: one was chosen...

Vertical flow constructed wetland (VFCW) is a promising technique for removal of excess nutrients and certain pollutants from wastewaters. The aim of this study was to develop a STELLA (structural thinking, experiential learning laboratory with animation) model for estimating phosphorus (P) removal in an artificial VFCW (i.e., a substrate column with six zones) grown with umbrella papyrus (Cyperus alternifolius) species under a wetting-to-drying cycle. Simulations showed that rate of soluble P (SP) leaching was highest at the top zone (i.e., Zone 1) and decreased gradually with increasing...

Background: Forest managers must deal with inherently stochastic ecological and economic processes. The future growth of trees is uncertain, and so is their value. The randomness of low-impact, high frequency or rare catastrophic shocks in forest growth has significant implications in shaping the mix of tree species and the forest landscape. In addition, the fluctuations of wood prices influence greatly forest revenues. Methods: Markov decision process models (MDPs) offer a rigorous and practical way of developing optimum management strategies, given these multiple sources of risk....

The objective of this study was to determine the effect of the monetary union on the trade of forest products between euro-using countries. A differential gravity model of bilateral trade flows was developed and estimated with data for the bilateral trade between 12 euro countries from 1988 to 2013, for commodity groups HS44 (wood and articles of wood), HS47 (pulp of wood, fibrous cellulosic material, waste, etc…), HS48 (paper and paperboard), and their sum. The results showed a positive or neutral effect of the euro on trade, for all products and countries, with three estimation methods....

Mangroves are well-known for their numerous ecosystem services, including storing a globally significant C pool. There is increasing interest in the inclusion of mangroves in national climate change mitigation and adaptation plans in developing nations as they become involved with incentive programs for climate change mitigation. The quality and precision of data required by these programs necessitates the use of an inventory approach that allows for quantification, rather than general characterization, of C stocks. In this study, we quantified the ecosystem C stock of the Zambezi River...

The principle findings of the 2013 forest survey in the State of Mississippi and changes that have occurred since previous surveys are presented. Topics examined include forest area, ownership, forest-type groups, stand structure, timber volume, growth, removals, and mortality. Emerald ash borer and invasive plants are also discussed in the context of Mississippi’s forests.

This resource update provides an overview of forest resources in South Carolina. Information for this factsheet was updated by means of the Forest Inventory and Analysis (FIA) annualized sample design. Each year 20 percent of the sample plots (one panel) in South Carolina are measured by field crews, the data compiled, and new estimates produced. After 5 years of measurements, the full sample (a cycle) is complete and a new survey cycle begins. The most reliable trend information (especially that concerning magnitude of change) comes from comparing two full cycles of data. Estimates...

We have three goals. (1) To develop a suite of functionally relevant climate variables for modelling vegetation distribution on arid and semi-arid landscapes of the Great Basin, USA. (2) To compare the predictive power of vegetation distribution models based on mechanistically proximate factors (water deficit variables) and factors that are more mechanistically removed from a plant’s use of water (precipitation). (3) To quantify the climate gradients that control shrub distributions in a cold desert environment.

The US Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), Aberdeen Plant Materials Center, Aberdeen, Idaho, announces the release of Amethyst Germplasm hoary tansyaster (Machaeronthero canescens (Pursh) A. Gray [Asteraceae]}, a selected class natural track germplasm identified by NRCS accession number 9076670 for conservation plantings in the Intermountain US. Amethyst Germplasm hoary tansyaster is a native forb collected near St Anthony Sand Dunes in Fremont County, Idaho. This forb flowers and produces seed during the first growing season and provides late...