Treesearch

Thinning of conifers followed by pile burning has become a popular treatment to reduce fuel loads in the Lake Tahoe Basin. However, concern has been voiced about burning within or near riparian areas because of the potential effect on nutrient release and, ultimately, lake water quality. Our objective was to quantify the effects of pile burning on soil physical and chemical properties and resulting near-stream surface and subsurface water chemistry. Twenty-seven hand-built piles of three contrasting fuelbed types (large wood; mixed-diameter slash; small-diameter slash) were assessed. Burn...

We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements were analyzed for control, low N (LN, 50 kg NH4NO3 ha-1 year-1) and high N (HN, 150 kg NH4NO3 ha-1 year-1) treatments. In the pine stands, partitioning of excess N into foliar PAs and AAs increased with both N treatments...

Data from Georgia timber product output studies were used to develop models that spatially allocate roundwood receipts data from primary wood-using mills. Mill receipts data were converted to a cumulative frequency based on a distance from the mill to a county center. Distances were calculated as either straight line or shortest road distance, and county centers were determined as geographic centers or weighted by forest mass. Logistic and Gompertz nonlinear asymptotic model forms were used to model cumulative frequency of annual receipts within a repeated measures framework. It was...

Emerald ash borer (EAB), Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), is a non-native, wood-boring beetle that has caused widespread mortality of ash (Fraxinus Linnaeus (Oleaceae)) in eastern North America. During 2004-2007, we determined whether forest community composition and structure of black (F. nigra Marshall), green (F. pennsylvanica Marshall), and white (F. americana Linnaeus) ash stands influenced their susceptibility to EAB invasion in southeast Michigan, United States of America. There was no relationship between EAB-induced ash decline or percentage mortality and...

Water yield, water supply and quality, wildlife habitat, and ecosystem productivity and services are important societal concerns for natural resource management in the 21st century. Watershed-scale ecohydrologic studies can provide needed context for addressing complex spatial and temporal dynamics of these functions and services. This study was conducted on the 5240 ha Turkey Creek watershed (WS 78) draining a 3rd order stream on the Santee Experimental Forest within the South Carolina Atlantic Coastal Plain, USA. The study objectives were to present the hydrologic characteristics of this...

A study was initiated to investigate the sustainability effects of intercropping switchgrass (Panicum virgatum L.) in a loblolly pine (Pinus taeda L.) plantation. This forest-based biofuel system could possibly provide biomass from the perennial energy grass while maintaining the economics and environmental benefits of a forest managed for sawtimber. Operations necessary for successful switchgrass establishment and growth, such as site preparation, planting, fertilizing, mowing and baling, may affect hydrology and nutrient runoff. The objectives of this study were (i) to characterize the...

A forest is a biotic community predominated by trees and woody vegetation types that are significantly taller, greater, thicker, and deeper than other vegetation types and generally covers a large area (Chang, 2003). Forests cover approximately 26.2% of the world, with 45.7% of Latin American and the Caribbean being covered, 35% of East Asia and the Pacific, and 35% of the European Union. Canada and the United States (U.S) combined account only for 6.8% of the world’s forests while Africa has even less 5.7% (Forest Types of the World, 2013). In the U.S., forests cover about one-third of...

This publication provides an overview of forest resources in Vermont based on inventories conducted by the U.S. Forest Service Forest Inventory and Analysis (FIA) program of the Northern Research Station. For annual inventory years 2003-2013, the cycle length was equal to 5 years. Beginning in 2014, the cycle length was changed to 7 years. For the 2014 inventory, estimates for current variables such as area, volume, and biomass are based on 1074 plot samples collected from 2009-2014. Change variables such as net growth, removals, and mortality are based on 964 samples collected in 2004-2009...

Urban tree survival is essential to sustain the ecosystem services of urban forests and monitoring is needed to accurately assess benefits. While some urban forestry studies have reported street tree survival, little is known about the factors influencing residential yard tree survival, especially over the long-term. We assessed residential shade tree survival in Sacramento, California over 22 years. Tree survival data were collected through field surveys and aerial photointerpretation. Survival analysis was used to evaluate longitudinal tree survivorship. Multivariate logistic regression...

Forecasting the effects of climate change on threatened ecosystems and species will require an understanding of how weather influences processes that drive population dynamics. We have evaluated weather effects on activity patterns of western ratsnakes, a widespread predator of birds and small mammals in eastern North America. From 2010-2013 we radio-tracked 53 ratsnakes in the fragmented region of central Missouri. We relocated each snake 4x per week and used movement frequency as an index of activity. We used generalized linear mixed models within an information–theoretic approach to...