Pentachlorophenol (penta) is no longer going to be available as a wood pole preservative, which has caused utilities to change their pole specifications to include different preservative treatments. Several other oilborne treatment options exist to fill the gap, and one currently being utilized as a replacement is 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOI). However, currently available solvent systems are chemically different than those available ~30 years ago when previous solvent tests were performed using this system. This work sought to compare the performance of DCOI delivered to southern pine or Douglas-fir wood using one of three different solvent systems against decay fungi according to the American Wood Protection Association (AWPA) E10 standard. Wood Blocks (19 mm) were treated to three different retention levels, AWPA UC4B retentions, 0.5 kg/m 3 (0.031 pcf), and 0.25 kg/m 3 (0.016 pcf) using three different solvent systems. The solvent systems used were RHT-70, a P9 oil not meeting penta solvency requirement; HBB-30, a P9 oil with a biodiesel additive for penta solvency; and #2 diesel oil. Blocks were subjected to an accelerated weathering protocol prior to exposure to two brown rot and one white rot fungus for 12 and 16 weeks, respectively. Performance was assessed by mass loss at the end of the incubation period. All solvent systems performed well against decay fungi when treated to UC4B retentions. Mass losses for the 0.5 kg/m 3 (0.031 pcf) treatment in all solvents averaged from about 15-25% when exposed to brown rot fungi. These mass loss values were notably higher than was seen in previous work using solvent systems available in the 1980s at similar chemical retentions. No obvious patterns in performance were seen among the different solvent systems used in this study.

Naturally durable wood species such as western juniper (Juniperus occidentalis) are a potential source of bio-based wood preservatives for the improvement of non-durable timber species. This research investigated the durability of southern yellow pine (Pinus sp.) and western juniper lumber or strandboard. Single layer panels were made with six different types of wood or wood treatments: southern yellow pine, mixed juniper sapwood and heartwood, sapwood, heartwood, sapwood strands impregnated with juniper oil prior to and after panel manufacturing. Panels were fabricated with 560 kg/m3 oven-dry density with 5% of PF resin and 0.5% of wax. Durability testing was performed with the brown rot fungi Gloeophyllum trabeum and Rhodonia placenta and the white rot fungus Trametes versicolor. Internal bond as a crucial parameter of OSB was measured. Tests revealed that juniper heartwood and juniper heartwood strandboards were highly decay resistant, and juniper oil pre- and post-impregnation strandboard manufacture imparted increased resistance to decay against one brown rot fungus, Gloeophyllum trabeum. Juniper strandboard manufactured from non-impregnated strands showed significantly higher internal bond than pine. These results suggest there is excellent potential for manufacturing highly decay-resistant OSB from juniper, especially from heartwood and that juniper oil can increase the durability of juniper sapwood strandboard.

High throughput sequencing has quickly become a standard method for studying fungal ecology but comparing results with more classic methods of culture isolation remains a challenge; especially for predicting ecological functions like decay. In this test, we compared Illumina sequencing of fungal ITS2 sequences with 325 fungal cultures isolated from the same 550 wood-core samples taken from 196 air-seasoned red oak or blackgum logs over three sampling dates. Fungi were more abundant on blackgum than red oak at all sampling times, reflecting the inherent resistance of these two species to fungal attack. While there was some overlap in fungal genera identified using the two characterization methods, the differences made it difficult to directly compare results. Illumina sequencing data suggested that many more fungi were present in the seasoning timbers, although their possible ecological roles remain unknown. The results suggest the need for more detailed studies comparing results for the two methods under more controlled conditions to better understand the information generated in relation to the actual decay environment.

Glyphosate is the most widely-used herbicide worldwide and while its effects on bacteria have been extensively studied, effects on fungi are less known. Understanding how long-term glyphosate use changes fungal decomposition capabilities will become increasingly important. The effect of glyphosate on wood-decay, an essential ecosystem service primarily performed by basidiomycetes, has received little attention. To explore this, we asked, "does repeated, long-term glyphosate application impact soil and wood fungal communities" and "does glyphosate exposure alter wood-decay processes?" Untreated southern pine sapwood stakes were exposed in ground contact using a matched-pair plot design (glyphosate/no glyphosate) with four blocks at each of three sites. Destructive harvests were planned every six months for five years. At each sampling: • eight stakes/plot were visually rated for decay progression and returned • two soil samples, before and after glyphosate application, and one stake were collected for fungal community analysis of the ITS2 region using Illumina MiSeq. The sequence data will fill a knowledge gap regarding the effects of vegetation management on fungal communities. Coupling these data with a specific ecosystem function (wood-decomposition) will help gain a deeper understanding of the functional influence of targeted taxa and the impact of glyphosate on the system.

Biological durability issues in cross-laminated timber (CLT) have been majorly ignored in North America because of the European origin of the material and careful construction practices in Europe. However, the risks of fungal and insect attacks are increased by the North American climatic conditions and lack of job-site measures to keep the material dry. The methods to evaluate durability in solid timber are inadequate for use in mass timber (MT) for a number of reasons, such as moisture variation and size being critical issues. This study therefore proposes a method, which is suitable to evaluate the strength of MT assemblies that are exposed to fungal degradation. The objective of the study was to explore a controlled method for assessing the effects of wetting and subsequent fungal attack on the behavior of CLT connections. Two different methods were used to create fungal attack on CLT assemblies. Although they were both successful, one was cumbersome, left room for many errors, and was not as efficient as the other. In addition, a standardized method to evaluate and characterize key performance metric for the connections is presented.