Treesearch

Acorn production varies considerably among species, locations, and years with potential effects on populations of acorn-consuming wildlife, oak (Quercus spp.) regeneration, and forest ecology. Methods to estimate annual acorn crop size include acorn-trapping (quantitative) or visual surveys (indices or ranks). Forest managers need a tool for converting visual survey data to quantitative estimates of acorn yield within specific years and areas. I used 7 years (2006–2010, 2012, 2016) of visual acorn survey data with acorn trap data from the same individual trees of 5 common eastern oak...

This report summarizes information on the use of wood from hardwood species in engineered materials, components, and structures. It includes information on use in a wide variety of engineering products and applications.

Assessing the ecological and economic impacts of non-native species is crucial to providing managers and policymakers with the information necessary to respond effectively. Most non-native species have minimal impacts on the environment in which they are introduced, but a small fraction are highly deleterious. The definition of 'damaging' or 'high-impact' varies based on the factors determined to be valuable by an individual or group, but interpretations of whether non-native species meet particular definitions can be influenced by the interpreter's bias or level of expertise, or lack of...

This study evaluated maleic acid (MA) as a green hydrotrope for efficient wood fractionation at atmospheric pressure and ≤100 °C. MA hydrotropic fractionation (MAHF) resulted in esterified lignin with a low degree of condensation and a very light color. 2D 1H–13C HSQC and HMBC NMR analyses of reaction products of a lignin model compound guaiacylglycerol-beta-guaiacyl ether with MA identified bonding through the γ-OH group. The surface charge of lignocellulosic MAHF water insoluble solids (WIS), induced by lignin esterification (carboxylation), enhanced enzymatic sugar yield by reducing...

In the United States, wood has been traditionally used in residential construction. However, the combustibility of wood still limits its use as a building material in prescriptive building codes, and to overcome the limitations, performance‐based codes can be used. In order to properly analyze performance‐based designs, more information on the fire performance of materials is required, including fire performance under different fire exposures. The char rate when timber elements are exposed to the standard time‐temperature curve have been well characterized and can be used to determine the...

Large wildfires can have profound and lasting impacts not only from direct consumption of vegetation but also longerterm effects such as persistent soil erosion. The 2002 Hayman Fire burned in one of the watersheds supplying water to the Denver metropolitan area; thus there was concern regarding hillslope erosion and sedimentation in the reservoirs. The efficacy of various treatments for reducing erosion was tested, including hand scarification on contour, agricultural straw mulch, wood mulch, burned controls and unburned reference plots. Simulated rill erosion experiments were used both...

We hypothesized that physiological and morphological responses to prescribed fire support the post-scorch foliage recovery and growth of young longleaf pine. Two studies conducted in central Louisiana identified three means of foliage regrowth after fire that included an increase in the gas exchange rate of surviving foliage for 3 to 4 months after fire. Saplings also exhibited crown developmental responses to repeated fire that reduced the risk of future crown scorch. Starch reserves were a source of carbon for post-scorch foliage regrowth when fire was applied in the early growing...

An exceptionally powerful storm struck southwestern Washington in December 2007 causing large debris flows in two adjacent streams. The two affected streams had been studied prior to the storm, providing a rare opportunity to examine ecosystem recovery. We monitored the streams and their riparian zones for six years after the disturbances to determine whether recovery rates of biota, physical habitat, and water temperature differed, and if so, what factors affected resilience. Along both streams, the debris flows removed wide swaths of soil, rock, and coniferous riparian forests, widening...

Given the increasing interest in the use of lidar-based remote sensing to support carbon monitoring systems, including those used for measurement, reporting, and verification requirements for REDD+ (reduced emissions from deforestation and degradation) programs in tropical nations, there is a corresponding need for the cost-effective field measurement systems to enable model development and robust assessment of uncertainty in these programs. In this report, we describe an efficient field sampling design and measurement protocol designed to provide field-based estimates of biomass/carbon...

Public lands provide opportunities and settings for people to experience nature and the outdoors. These outdoor experiences are important for human health and well-being and result in visitor spending that benefits local communities. This report shows that new research, tools, and frameworks are needed to help us find new ways to conceptualize outdoor recreation and enhance the ability of public land managers to provide outdoor experiences while protecting natural and cultural resources. The report originated from a set of 17 working papers that were developed as part of an initiative...