Treesearch

Field trials were designed to evaluate the ability of the experimental wood preservative N’N-naphthaloylhydroxylamine (NHA) to inhibit fungal decay and termite damage at the USDA Harrison Experimental Forest (HEF) in Saucier, MS. Twenty replicate 19 x 19 x 457 mm (0.75 x 0.75 x 18 in.) southern yellow pine stakes and 10 replicate 19 x 19 x 76 mm (0.75 x 0.75 x 3 in.) blocks were pressure treated with three concentrations of aqueous NHA (0.f1, 0.5, and 1%). One percent CCA-C served as positive control. The smaller specimens were designed to favor termite attack by inserting the test...

Determining a “corrosion-lifetime” for fasteners embedded in wood treated with recently adopted preservative systems depends upon successfully relating results of laboratory tests to in-service conditions. In contrast to laboratory tests where metal is embedded in wood at constant temperature and moisture content, the in-service temperature and moisture content of wood exhibit large fluctuations which affect the corrosion rate. The paper presents an approach for determining the corrosion lifetime of fasteners in which the calculated wood moisture content at the wood-fastener interface is...

Synthetic adhesives, including urea-formaldehyde (UF) and phenol-formaldehyde (PF), have generally replaced biobased adhesives over the past 70 years because of their durability, low cost, and ease of use. However, in the past few years, concern about formaldehyde emissions, cost, and interest in biobased materials have renewed interest in soy adhesives. The use of soy adhesives can be broken into four stages: soy flour selection, dispersing/denaturating conditions, cross-linking chemistry, and bonding conditions. Generally soy flour is used because of its low cost, but the adhesive...

A statistical analysis was performed that identified time trends in the Scheffer Index value for 167 locations in the conterminous United States over the period 1969-2008. Year-to-year variation in Index values was found to be larger than year-to-year variation in most other weather parameters. Despite the substantial yearly variation, regression equations, with time (year) as the independent variable could be fit to the Scheffer Index data. A linear regression was found to provide appropriate fit when square-root transformations of Scheffer Index values were used as the dependent variable,...

Currrent standards for soil-block testing have long been based on the effectiveness of preservative systems against only a small number of wood decay fungi and even fewer bacteria. Culture-independent molecular methods offer simple, reproducible means to obtain a more holistic view of the microbial communities that colonize wood throughout the decay process. By using a culture-independent PCR-based method called terminal restriction fragment length polymorphism (T-RFLP) analysis, we were able to detect shifts of fungal and bacterial communities in wood treated with sub-lethal concentrations...

This study evaluated dioctylaminoborate in wood for fungal decay protection Dioctylaminoborate was synthesized by refluxing dioctylamine and boric acid in 1:1 molar ratio in ethanol for 4 h. The product was characterized by proton Nuclear Magnetic Resonance Spectrophotometry (1H-NMR) and Fourier Transform Infrared Spectrophotometry (FTIR). Dioctylaminoborate prevented decay in loblolly pine (Pinus Teada L.) by the brown rot fungus, Gloeophyllum trabeum (Gt). The leached specimens with chemical retention of 12.6% had weight loss of 1% by Gt. The non-leached specimens with chemical retention...

The goals of this study were to evaluate borate/amine/zinc formulations in wood for fungal decay protection as well as the permanence of zinc and boron in wood. Wood treated with each of four formulations of borate/amine/zinc prevented or decreased fungal degradation after a 12-week AWPA Standard soil-block test. For non-leached specimens, wood treated with borax/amine/zinc formulations required retention of 1.2% to prevent decay by Gloeophyllum trabeum (Gt) and Trametes versicolor (Tv), whereas that of DOT/amine/zinc formulations required 0.6% to be effective. For leached specimens, only...

For decades the phrase “point 4” was synonymous with wood treated for use in contact with the ground. In this paper we review how and why the 0.4 lb/ft3 (6.4 kg/m3) retention became such an accepted standard, and then evaluate how well this retention has performed in long term stake testing. Data from plots near Saucier, Mississippi that contained southern pine 2 by 4 nominal (38 by 89 mm) stakes pressure treated with either ACA, CCA-A, CCA-B or CCA-C were evaluated. The plots ranged in age from 20 to 61 years. The data indicate that the 0.4 lb/ft3 (6.4 kg/m3) retention has provided good,...

Carbon-encapsulated metal nanoparticles were synthesized by thermal treatment of wood char, with or without transition metal ions pre-impregnated, at 900ºC to 1,100ºC. Nanoparticles with concentric multilayer shells were observed. The nanoparticles were analyzed by scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDX) spectroscopy. The EDX spectrum showed that carbon was the dominant element in the shells. TEM and XRD analysis indicated that the generated carbon shells had structures similar to that of graphite with...

Although higher treatment pressures have the potential to improve preservative penetration, higher pressures may possibly result in greater reduction in mechanical properties. The present study evaluated the effect of treatment pressure on the treatment quality and mechanical properties of red pine (Pinus resinosa Ait.) lumber. End-matched sections of red pine lumber were treated with an ethanolamine copper preservative at pressures of 1,207 kPa (175 psi), 1,379 kPa (200 psi), or 1,551 kPa (225 psi). Preservative uptake and penetration were measured, and small clear specimens were subsequen...