Treesearch

A method is suggested for estimating additions to carbon stored in harvested wood products (HWP) and for evaluating uncertainty. The method uses data on HWP production and trade from several decades and tracks annual additions to pools of HWP in use, removals from use, additions to solid waste disposal sites (SWDS), and decay from SWDS. The method is consistent with IPCC guidance for estimating emissions from SWDS. Uncertainty is postulated in the form of probability density functions for 14 variables, using Monte Carlo simulation. A method is suggested for estimating additions to carbon...

When the time comes for a consumer to select the wood and finish types for a given outdoor project, there is a wide variety of sources of information, articles, and opinions available. Occasionally, these sources will conflict, mostly due to the data available at the time of publication, or practical experience based on a snapshot of conditions at a given time period. It is our hope to make this article available as a tool for the consumer to weed through the confusion, obtain the best system for the particular application, and understand the compromises that can result from other choices....

This chapter discusses several issues regarding reommended protocols for sampling macrofungi: Opportunistic sampling of macrofungi, sampling conspicuous macrofungi using fixed-size, sampling small Ascomycetes using microplots, and sampling a fixed number of downed logs.

Phosphorus from excess fertilizers and detergents ends up washing into lakes, creeks, and rivers. This overabundance of phosphorus causes excessive aquatic plant and algae growth and depletes the dissolved oxygen supply in the water. In this study, aluminum-impregnated mesoporous adsorbents were tested for their ability to remove phosphate from water. The surface structure of the materials was investigated with X-ray diffraction (XRD), a N2 adsorption-desorption technique, Fourier transform-infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS) to understand the effect of surface...

One potential use for small-diameter ponderosa pine and Douglas-fir timber is in log form. Many potential uses of logs require some degree of drying. Even though these small diameters may be considered small in the forestry context, their size when compared to typical lumber thickness dimensions is large. These logs, however, may require uneconomically long kiln-drying time. Air-drying is a logical alternative to kiln drying, but the variables involved make estimating air-drying times difficult. In this study, experimental air-drying time data for 4- to 8-inch- (102- to 203-mm-) diameter...

This paper evaluates the relationship between the stress wave velocities of green and dry southern pine and Douglas-fir veneers. A commercial stress wave timer and a laboratory signal analysis system were used to measure the transit time required for an induced stress wave to travel the longitudinal length of each veneer. Stress wave transit times were measured in the veneers in the wet condition and at a dry equilibrated moisture content of approximately 10 percent. A strong linear relationship was found between green and dry stress wave velocity for both southern pine and Douglas-fir...

In October 2004, Committee D-7 on Wood of the American Society for Testing and Materials (ASTM) is celebrating 100 years of contributions to the safe and efficient use of wood as a building material. Born during a period of rapid social, economic, and technological change, the Committee faced controversial issues and the challenge of a changing forest resource. This article highlights the technical and economic challenges we have faced over the years, discusses some of the controversial decisions, and speculates on future challenges.

Current grading standards for logs used in log home construction use visual criteria to sort logs into either “wall logs” or structural logs (round and sawn round timbers). The conservative nature of this grading system, and the grouping of stronger and weaker species for marketing purposes, probably results in the specification of logs with larger diameter than would be required if a more precise grading method were available. This study evaluated the relationships between log strength and stiffness as a basis for a mechanical grading system. A sample of 120 logs, 4.9-m (16-ft.) long, was...

The purpose of this study was to evaluate two groups of composite panels made from two types of underutilized natural fiber sources, kenaf bast fiber and office wastepaper, for their suitability in composite panels. All panels were made with 5% thermosetting phenol-formaldehyde (PF) resin and 1.5% wax. Also, an additional 10% polypropylene (PP) thermoplastic resin was used in half the panels. The PP was added to determine the effect it had on the mechanical and physical properties of the panels. The resin and wax were applied with a pneumatic spray gun while tumbling the fiber in a rotary...

Certain issues in recent softwood lumber trade negotiations have centered on the method for converting estimates of timber volumes reported in cubic meters to board feet. Such conversions depend on many factors; three of the most important of these are log length, diameter, and taper. Average log diameters vary by region and have declined in the western United States due to the growing scarcity of large diameter, old-growth trees. Such a systematic reduction in size in the log population affects volume conversions from cubic units to board feet, which makes traditional rule of thumb...