Treesearch

Since the summer of 1996, a project has been underway at the University of Wisconsin-Madison,Dept. of Plant Pathology, to determine how different forest management regimes can affect the diversity of fungi found in northern hardwood forests. This report is an introduction to this project's goals, objectives and methods. A particular group of fungi, the wood-inhabiting polyporoid and corticioid fungi (commonly known as the polypores and the crust fungi), was chosen for this project. To date, fruiting bodies have been sampled for two years in forest stands in northern Wisconsin and the...

To date, there is no standard method for evaluating the structural integrity of wood floor systems using nondestructive techniques. Current methods of examination and assessment are often subjective and therefore tend to yield imprecise or variable results. For this reason, estimates of allowable wood floor loads are often conservative. The assignment of conservatively low, allowable floor loads often means that the continued use, or adaptive use, of an historic building is uneconomical, resulting in demolition of inappropriate rehabilitation. Successful completion of this project will...

Preservative-treated wood products are important construction materials. Preservative-treated wood pilings, after removal from service, constitute a major disposal problem for managers of waterfront facilities. For example, approximately 7,000 to 8,000 tons of mechanically or biologically deteriorated wood pilings are currently removed from U.S. naval facilities annually. While many of these poles are no longer useful for piles, a considerable amount of the wood in them may be used for other exterior applications. The key to using the sound wood in these poles is the development of a...

The continuous lumber tester (CLT) is the most widely used grading machine in the world. With the CLT, the flatwise bending stiffness of lumber is measured as it passes through the machine. The modulus of elasticity (MOE) is calculated from the force required to bend the lumber to a fixed deflection of 7.94 mm (5/16 in.), and this MOE is used in assigning a machine grade. Quality control testing is also required to assure proper grade assignment. Usually, quality control is based on tests of bending stiffness and strength. In commercial practice, the lumber passing through the CLT may...

This study sought to determine the effect of fixation time and temperature on the release of copper, chromium and arsenic from treated marine piles immersed in seawater under "worst case" conditions. Sections of piles were CCA-C treated to a target retention of 2.5 lbs/ft3) (40 kg/m3) and then allowed to Condition at 36°F (2°C) for either 3, 7 or 20 days. As a control, one set of "wel1 fixed'' pile sections was conditioned at 80°F (27°C) for 20 days prior to leaching. Following the designated fixation period, the sections were leached in seawater maintained at 36 °F (2 °C). Fixation...

Longitudinal stress wave nondestructive evaluation (NDE) techniques have been used in a variety of applications in the forest products industry. Recently, it has been shown that they can significantly aid in the assessment of log quality, particularly when they are used to predict performance of structural lumber obtained from a log. The purpose of the research described in this report was to investigate the use of stress-wave- based techniques for assessing the potential quality of veneer obtained from logs. Sixty-two ponderosa pine veneer blocks from 22 tree-length logs were nondestructiv...

Sphaeroma terebrans Bate is a widespread estuarine, wood-boring, isopod found in red mangrove (Rhizophora mangle) forests of tropical and subtropical estuarine waters. Because it causes extensive damage to man-made structures in marine coastal zones and is resistant to common methods of wood preservation it is important to understand fully how S. terebrans uses the wood into which it bores. Previous studies indicate that S. terebrans is primarily a filler-feeder and does not utilize bored wood as a nutritive substrate. However, laboratory feeding data obtained in this study indicate that...

Three stilbenes, pinosylvin (PS), pinosylvin monomethyl ether (PSM) and pinosylvin dimethyl ether (PSD), were extracted from white spruce (Picea glauca), jack pine (Pinus banksiana), and red pine (Pinus resinosa) pine cones, and their structures were confirmed by spectroscopic and chromatographic (HPLC, GC/MS, NMR and FTIR) analysis. PS, PSM, PSD or a 1:1:1 mixture of these stilbenes at concentrations of 0.1% and 1.0% were examined for their fungal inhibitory activity by two bioassay methods. Growth of white-rot fungi (Trametes versicolor and Phanerochaete chrysosporium), and brown-rot...

Ultrasonic inspection of lumber has been under investigation for over 20 years, with little commercial impact. Recently, the USDA Forest Products Laboratory (FPL) developed ultrasound-based scanning technology to examine both green and dried lumber. In green lumber, the bacterial infection called wetwood (a significant source of degradation in oak at the kiln-drying stage) was found with high accuracy using time-of-flight techniques. A similar approach was used to locate checking and honeycombing in dried lumber, defects that are often not apparent by external visual inspection. This...

The unmitigated pest risk potential for the importation of Pinus and Abies logs from all states of Mexico into the United States was assessed by estimating the probability and consequences of establishment of representative insects and pathogens of concern. Twenty-two individual pest risk assessments were prepared for Pinus logs, twelve dealing with insects and ten with pathogens. Six individual assessments were prepared for Abies logs. The selected organisms were representative examples of insects and pathogens found on the bark, in the bark, and in the wood of Pinus or Abies logs. Among...