Treesearch

Small-diameter and underutilized (SDU) material refers to the timber that is left in the forest because it is not economical to remove, or local capacity to process it does not exist. SDU material also includes the dense, understory present through-out the forest as a result of 50 years of successful fire suppression. It has become apparent that there are many beneficial forest management reasons why this material should be removed, including reducing fire hazards, altering the stand species and quality mix to a more desirable composition, providing healthier wildlife habitat, and protectin...

This report describes the long-term performance of painted window units that were placed outdoors near Madison, Wisconsin, in 1956. Covered in this report are the effects of the initial water repellent preservative (WRP) treatment during the first 6 years of exposure, a comparison of the water repellent effectiveness (WRE) ofthe WRP with the condition of the windows after 32 years, restoration of the windows after 32 years, paint performance after the restoration, and the final evaluation for decay after 45 years. There was no correlation between the WRE of the treating solutions as...

From an early status as a “weed tree,” poplar has become an important commercial genus in North America during the past 20 years. The many and varied uses of poplar wood now include pulp and paper, lumber, veneer, plywood, composite panels, structural composite lumber, containers, pallets, furniture components, match splints and chopsticks.The high cellulose and relatively low lignin content make poplars well suited for pulp and paper products. Thewood can be pulped by all commercial pulping methods, such as mechanical, semi-chemical, sulphate and sulphite processes. Poplar pulps are...

Wood is a thermally degradable and combustible material. Applications range from a biomass providing useful energy to a building material with unique properties. Wood products can contribute to unwanted fires and be destroyed as well. Minor amounts of thermal degradation adversely affect structural properties. Therefore, knowledge of the thermal degradation and fire performance of wood can be critical in many applications. Chemical treatments are available to improve fire performance characteristics.

Wood-plastic composites are being examined for a greater number of structural-type applications that may be exposed to different environments, some of them adverse. This paper discusses the influence of moisture absorption on the mechanical proper-ties of wood flour-polypropylene composites. Composites filled with 20% or 40% wood flour (by weight) were placed in different environments, removed periodically, and tested for moisture content and mechanical properties. The composites filled with 20% wood flour (20% WF) absorbed moisture in all the environmental exposures, but no significantdegr...

This chapter on wood adhesives includes: 1) Classification of wood adhesives 2) Thermosetting wood adhesives 3) Thermoplastic adhesives, 4) Wood adhesives based on natural sources 5) Nonconventional bonding of wood 6) Wood bonding.

Mechanical, chemical, and light microscopic methods were used to observe wood cell wall changes during colonization by Ceriporiopsis submervispora. Maximum crushing load, dynamic mechanical analysis (DMA), and quantitative Simon’s staining were found to be the most useful methods for tracking biopulping action. MOE and loss modulus trended downward within 2 days of inoculation, even though few cells were colonized by that time. Quantitative Simon’s staining results were highly correlated with refiner energy savings.

Some instances of severe warping of siding treated with a commercial waterborne preservative have been reported to the authors. We investigated this problem by evaluating 25mm-, 51 -mm-, and 102-mm- (1-, 2,- and 4-in.-) thick chromated copper arsenate (CCA) treated No. 1 southern yellow pine lumber shipped from three suppliers to a secondary manufacturer in Louisiana. The moisture content (MC), CCA retention, and adsorption/ desorption ratio was determined for specimens cut from the lumber. For all lumber thicknesses and target retention levels, including untreated wood, the MC of many...

This is the second in a series of reports on the erosion rates of wood exposed outdoors near Madison, Wisconsin. In the work reported here, the erosion rates of earlywood and latewood were determined for smooth-planed vertical-grained lumber for an exposure period of 14 years. The specimens were oriented vertically, facing south; erosion was measured annually for the first 6 years and biannually the remainder of the exposure. Wood species were ponderosa pine, lodgepole pine, Engelmann spruce, western hemlock, and red alder. Large differences were observed between earlywood and latewood...

A new noninvasive technique has the potential to assess the in-place stiffness of timber floors.