New species introductions have been associated with the movement of
people for thousands of years. For instance, horses were introduced into North
America by Spanish explorers, while pigs were introduced by the Polynesians
into many Pacific islands long before the establishment of permanent
European settlements. Both of these species introductions...
Eight series of untreated posts (including five series of steel), 18 series of nonpressure-treated posts, and II series of pressure-treated posts remain in test at the Oregon State University post farm in western Oregon. So far all posts have failed in 36 untreated series, 33 nonpressure-treated series, and 2 pressure-treated...
Copper is an excellent biocide which has a long history of usage for protecting wood from deterioration, but some organisms have developed tolerance for this chemical. Copper tolerance among wood decay fungi is a poorly understood phenomenon that is gaining importance as cofactors such as arsenic and chromium are removed...
The use of the waterborne wood preservative, ammoniacal copper zinc
arsenate (ACZA), is likely to increase in the near future because of environmental
concerns associated with oilborne preservatives. Developing an understanding of the
permanence of this preservative in wood will become important from both
environmental and performance standpoints. Conventional thinking...
This report is one of a series issued in cooperation with the Air Force-Navy-Civil Subcommittee on Aircraft Design Criteria under the supervision of the Aircraft Committee of the Munitions Board.
The effects of incorporation of selected biocides on physical and mechanical properties of aspen strandboard were assessed using five copper-based preservatives or zinc borate at three retention levels. Tebuconazole or 4,5-dichloro-2-N-octyl-4-isothiazolin-3-one (DCOI) were added as co-biocides to selective copper-based treatments. Mold box tests showed that only panels treated with DCOI...
Over-the-counter (OTC) wood preservatives can provide wood with both a moisture barrier and fungicidal protection against biodeterioration, yet there is little comparative data on the performance of these preservatives. In this study, the potential of various low-toxicity, OTC preservatives was evaluated on five western wood species, western red cedar (Thuja...
Environmental restrictions have induced many sawmills to seek alternatives to pentachiorophenol (penta) and similar chlorinated phenols for controlling mold and fungal stains on green lumber during storage and shipment. For that purpose, ten alternative stain preventives were evaluated against a traditional penta product (Permatox 101) on studs of Douglas-fir [Pseudotsuga...
Environmental restrictions have induced many sawmills to seek alternatives to pentachlorophenol (penta) or similar chlorinated phenols to control fungal sapstains on green lumber. Five alternative preventives were evaluated against a traditional penta product (Permatox 101) on Douglas-fir, hem-fir, and pine lumber in an accelerated 6-week test on small specimens in...
Production of hardwood lumber (mostly red alder) has been a small but growing part of the forest products industry in the Pacific Northwest. In laboratory tests, Rodewod® 200 EC plus borax protected alder at nearly all levels tested. Eight other chemicals provided some protection at the highest level tested. Fungal-stain...
While the heartwood of many wood species exhibits excellent resistance to fungal and insect attack, this resistance is sometimes diminished in second-growth material of the same species. The reasons for the reduced durability are unclear, but they may reflect a combination of both higher proportions of sapwood as well as...
Boron and boron compounds have been long used for pressure treatment, dip-diffusion, and remedial treatments of wood because of their proven efficacy against fungi and insects. These materials are especially attractive because their high water solubility promotes deeper penetration into wood. Other useful properties of boron include its neutral pH,...
Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] lumber was
converted to flakes, which were dip treated with three concentrations
each of copper chrome arsenate Type C (CCA-C), and disodium octaborate
tetrahydrate (TIM-BOR). Azaconazole [1-[{2-(2,4-dichloropheny1)-1,3-
dioxolan-2-yl}methyl]-1H-1,2,4-triazole] was used as powder. The
flakeboard panels (305 x 304 x 13 mm) were made using phenolformaldehyde...
The purpose of this bulletin is to show how woods should be graded in order that they may be given uniform results when subjected to treatment with preservatives; it is intended for those interested in wood preservation.
The merits of the photoelastic coating technique as applied to
wood were evaluated. Comparative tests were made on 12 nominal
two-by-four Douglas Fir boards. The object of these tests was to
determine the limitations of this technique, such as accuracy and
complexity of experimental procedure. Correlation of the experimental
results...
Elasticity properties of wood studs are essential inputs for
the structural analysis of wood-stud wall systems.
A theoretical procedure was developed to determine the probability
distributions for the deflection-load relations of stud samples.
The procedure is based on the finite element analysis and a Monte-
Carlo type simulation and accounts...
Biaxial strength characteristics of wood-based structural panels were evaluated by
using analytical and experimental methods. Cruciform plywood specimens were tested
under biaxial tensile-tensile, compressive-compressive loadings in a symmetrically-jointed-
arm test fixture, which was mounted on a universal testing machine. Performance
of the test fixture was also evaluated during the tests....
A laboratory method for evaluating wood preservatives should provide in a comparatively short time an integrated measure of the relative permanence and fungus-inhibiting capacity of a product. There is as yet no generally acceptable laboratory method of this type. Systematic service records serve to bolster the reputation of established preservatives....
Polychlorinated dibenzo-p-dioxins (PCDD's) and
dibenzofurans (PCDF's) are environmental pollutants associated with the production and use of a number of industrial
chemicals. In addition, PCDD's and PCDF's are produced
during low temperature combustion of wastes containing
polyvinylchloride (PVC), chlorophenols, and a number of
other chemical precursors.
A significant source of environmental...
In investigating wood treatment as a possible processing option for Alaska forest products manufacturers, the double-diffusion method using sodium fluoride followed by a copper sulfate appeared to be the most advantageous approach. Yet, little information was available as to the chemical retention after treating and its resistance to leaching. Green...
Supercritical fluid (SCF) impregnation is a promising preservative treatment method, however, the development of SCF processes has been slowed by a limited understanding of the process. Developing a better understanding of the effects of various process parameters on treatment results would allow for a more rational development of SCF impregnation....
Experiments investigated how the fumigant methylisothiocyanate
(MIT), Douglas-fir wood at various moisture contents (MC), and the
wood decay fungus Poria carbonica Overh., interacted to govern
overall fumigant effectiveness.
MIT decomposed in wood to form non-MIT residues at rates of
about 0.16%, 0.9%, and 1.6% of the total bound MIT per...
This study seeks to determine the feasibility of
utilizing one vaporizable copper compound - bis-[1-
(dimethylamino)-2-propanolato] copper(II) (Cu(DMAP)₂ as a
potential wood preservative. The synthesis of Cu(DMAP)₂
was conducted in accordance with a method developed by
Buhro and Dingman, Washington University, St. Louis,
Missouri. The yields of Cu(DMAP)₂ synthesis were...
Plywood panels collected from thirty seven mills located
throughout the Pacific Northwest they were treated with chromated copper
arsenate Type C (CCA-C) or ammoniacal copper zinc arsenate (ACZA) using
modified full cell and full cell processes respectively. Preliminary
tests were performed to determine plywood sample size, replication, and
treating schedule....
The Pacific Coast variety of Douglas-fir was investigated.
The samples were tested using both forced and free vibrations. Transverse
vibrations were introduced by excitations on the side of the
samples. Forced vibrations were applied from 5000 to 0 hertz by a
vibration generator, and free vibrations were initiated by a...
Publication restrictions have been removed. This report is one of a series issued in cooperation with the Army Air Forces and the Bureau of Aeronautics under the supervision of the Aeronautical Board.
Efficient use of wood in structural applications depends
upon the accuracy with which we can predict the mechanical
behavior of members under load. Most methods of lumber grading
and laminated beam design depend upon statistical and/or
empirical techniques in which averaged properties for complete
members are derived. A knowledge of...