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Moisture sorption in fiber-thermoplastic composites leads to dimensional instability and biological attack. To determine the pick up of moisture this type of composite, aspen fiber/polypropylene composites were made using several different levels of aspen fiber (30 to 60% by weight) with and without the addition of a compatibilizer (maleic anhydride grafted polypropylene, MAPP). These composites were tested using short and long term water soaking, boiling water, cyclic liquid water and oven drying, and under various relative humidity conditions. As the level of fiber increased in the...

Chromated copper arsenate (CCA) treated wood has been used extensively in outdoor applications. The Environmental Protection Agency (EPA) and CCA producers recently reached an agreement to limit future use of CCA for some types of applications. One area of concern is the long-term accumulation of leached CCA in soil adjacent to treated wood structures. Interpreting soil measurements adjacent to in-service structures is difficult. The original treatment may be unknown, and there may be little historical data to indicate whether the site was previously exposed to contamination from constructi...

The growth of pulp and paper mills in the US from 1970 to 2000 depended mostly on size and age. Mills grew according to Gibrat’s law, and post-1970 mills grew faster than pre-1971 mills. Mills stopped growing at approximately 22 years of age. But most mills survived beyond that, thus growth was not necessary for survival, but characteristic of the early phase of the mill life cycle. Less integrated mills grew slower. So did more specialized mills and more so if they produced mostly paper. Mill location was uncorrelated with growth, but location mattered indirectly by facilitating or...

We analyzed the physical properties of wood chips incubated with Ceriporiopsis subvermispora and cultural parameters of biopulping incubations of Phanerochaete chrysosporium and C. subvermispora. Dynamic mechanical analyses indicated a reduction in the modulus of elasticity (MOE) and loss modulus of spruce during the time where the biopulping energy savings effect takes place. The data from measurements of the MOE at different moisture contents indicated the fiber saturation point (FSP) of spruce increased from 29% to 42% during biopulping. Chips were made into pulp, which was washed, and...

During the twentieth century the Jewish National Fund (JNF) planted more than 200 million trees in Israel. These newly developing forests provide an opportunity to study the development of fungal communities. This study was initiated to quantify taxa richness and abundance of wood-inhabiting corticioid and polyporoid fungi (including heterobasidiomycetes) in eight even-aged forests dominated by Pinus halepensis (Aleppo pine). Four of the stands were 5-15 years of age, and four were 30-45 years of age. Of the four younger stands, three were previously planted to P. halepensis. Each stand...

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.

In the 15 western states there are at least 28 million acres of forest that could benefit from some type of mechanical treatment to reduce hazardous fuel loading. It is estimated that about 60 percent of this area could be operationally accessible for treatment with a total biomass treatment volume of 345 million bone dry tons (bdt). Two-thirds of this forest area is on public lands. Most of the volume is in trees 6 inches diameter and greater that have conventional utilization opportunities. Transportation cost and distance to markets, however, may preclude actual recovery. Treatment...

A terrestrial wood-inhabiting pyrenomycete was collected numerous times in the Neotropics. It possesses superficial, clustered ascomata, large, distinctive ascus rings and strongly guttulate, fusiform ascospores. A second similar pyrenomycete was collected once in Costa Rica. They could not be placed into any known genus, so a new genus, Mirannulata, is described. Mirannulata samuelsii has hyaline, fusiform, three-septate ascospores while M. costaricensis has brown, fusiform, oneseptate ascospores. Mirannulata has a very large, chitinoid, double-layered ascus apical ring similar to that of...

In part I of the article we discussed sample preparation procedure and described various methods used for the measurement of microstickies. Some of the important features of different methods are highlighted in Table 1. Temperatures used in the measurement methods vary from room temperature in some cases, 45 °C to 65 °C in other cases. Sample size ranges from as low as 0.25 g to as high as 50 g. The working definition of microstickies, material passing through 150 μm or 100 μm slotted screen, is used in this study. Of the eight methods listed in Table 1, COD Method, PMV Microstickies...

The objective of this research was to investigate the use of a stress wave technology to evaluate the structural quality of small-diameter timber before harvest. One hundred and ninety-two Douglas-fir and ponderosa pine trees were sampled from four stands in southwestern Oregon and subjected to stress wave tests in the field. Twelve of the trees, six Douglas-fir and six ponderosa pine, were harvested and sawn into logs and lumber. The mechanical properties of wood were then assessed by both stress wave and static bending techniques in the laboratory. Results of this study indicated a...