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An American wood. Description of the distribution, growth, habit, wood, and wood properties of the species. Includes bibliographical references.

An American wood. Description of the distribution, growth, habit, wood, and wood properties of the species. Includes bibliographical references.

An American wood. Description of the distribution, growth, habit, wood, and wood properties of the species. Includes bibliographical references.

The natural look of wood siding, and the retention of that look, has become increasingly popular over the past several years. Many new commercial formulations are being offered for use as clear natural wood finishes. A successful finish will retain color, control mold and mildew, and minimize weathering. Some of these formulations contain a chemical as a mildewcide (fungicide, preservative) and/or a water repellent, and some do not. To evaluate several chemicals (alone or in combination with water repellents) as components of natural finish formulations, we dip-treated ponderosa pine...

The Purdue Plane Structures Analyzer (PPSA) is a computer program developed specifically for the analysis of wood structures. It uses recognized analysis procedures, in conjunction with recommendations of the 1982 National Design Specification for Wood Construction, to determine stresses and deflections of wood trusses and frames. The program offers several options for the analysis of member capacity, depending on lateral support conditions, strength property variations, and critical load assumptions. Tabulated output provides a summary report of the input analog as well as individual...

A critical literature review has been carried out on the influence of ventilation rate (N, hr.-1) and board loading (L, m2/m3) on steady state formaldehyde concentrations (Cs, ppm) resulting from particleboard and plywood emissions. Large differences exist among boards in the extent to which their formaldehyde concentrations change with N or L in laboratory chambers. Much of the concentration versus N and L data obtained from controlled chamber experiments can be described by a two-parameter equation involving the ratio N/L as the independent variable. Although this equation has a theoretic...

A critical review was made of the literature concerned with how the formaldehyde to urea mole ratio (F/U) affects formaldehyde emission from particleboard and plywood bonded with urea-formaldehyde (UF) adhesives, and how this ratio affects certain other adhesive and board properties. It is difficult to quantify the dependence of various properties on mole ratio or determine lower limits of mole ratio for a particular property because of the range in resin, board, and testing parameters used in the cited studies. However, the available data do at least suggest the following limitations on...

The Dean, Hibbsville, and Decatur bridges were constructed in southern Iowa during 1994. Each bridge is a simple-span, stress-laminated deck superstructure, approximately 7.3 m (24 ft) long, constructed from eastern cottonwood lumber. The performance of each bridge was monitored for approximately 2 years, beginning shortly after installation. Monitoring involved collecting and evaluating data pertaining to the moisture content and vertical creep of the wood decks, the force level of the stressing bars, and the behavior of the bridges under static load conditions. In addition, comprehensive...

The available supply of yellow poplar (Liriodendron tulipifera L.), its potential for new uses, and its continuing importance to the furniture industry have created a need to accumulate additional information about this species. As an aid to better utilization of this species, charts for determining cutting stock yields from yellow poplar lumber are presented for each of the five top grades. Adjustment charts present the changes for specified width cuttings, also by grade. Yield and cost comparisons are made for various grades and grade mixes, with a case study used for illustration. The...

Small wood panels treated with many different chemicals have been exposed to limnorian and teredine marine borers in the sea at Key West, Florida. These preservatives and treatments include creosotes with and without modification, waterborne salts, salt-creosote dual treatments, chemical modifications of wood, and modified polymers. In spite of the accelerated nature of this test, many treated panels remain free of attack after 13-1/2 years in the sea. Untreated panels have been badly damaged by marine borers in 6 to 18 months. Borer activity has lessened in recent years.