Abstract
Fungi cultured from air-seasoning blackgum and red oak timbers were assessed for their ability to cause wood decay using two hardwoods and one soft wood species in an AWPA E10 soil block test. Weight losses were greatest for bigleaf maple and tended to be much lower on southern pine. Almost a quarter of the 35 taxa tested caused less than 5 % weight loss, suggesting they posed a relatively low decay risk, even under ideal laboratory conditions; despite all fungi tested having the ability to depolymerize wood. Three of the four fungi causing the largest weight losses were brown-rot fungi, although brown-rot fungi represented only small proportion of the total isolates from the original hardwood timbers. These results illustrate wide array of decay capabilities of fungi colonizing air-seasoning red oak and blackgum timbers, and the potential of many isolates to negatively affect wood properties through biodeterioration
Highlights
Large timbers, such as railroad ties, are commonly air-seasoned to remove moisture prior to preservative treatment
Exposure of G. trabeum or R. placenta to southern pine resulted in weight losses of 32,9 % and 35,2 %, respectively, which was slightly below the required 40% target level in the AWPA E10 standard
Mass losses for pine blocks exposed to T. versicolor only experienced 18,1 % weight loss; but whiterot fungi tend to perform poorly on pine sapwood or softwoods in the soil block test (AWPA 2017b)
Summary
Large timbers, such as railroad ties, are commonly air-seasoned to remove moisture prior to preservative treatment. Air-seasoning is simple and economical, but it potentially exposes wet, untreated timber to fungal attack. Some of the first studies of decay during air-seasoning were performed on railroad ties, using fungal fruiting bodies as decay indicators (Humphrey and Richards 1939). These studies led to the development of guidelines for proper air-seasoning, including keeping timbers out of direct soil contact, creating adequate airflow, and removing woody debris around the site, and minimizing the potential for standing water (Humphrey and Richards 1939, AWPA 2017a, AREMA 2019). The goal is to minimize fungal attack during air-seasoning and ensure the timbers are subjected to some form of sterilization (usually as heating over a minimum temperature such as 67 oC for 75 minutes) during preservative treatment. Most soil block tests have focused on wood durability and protective treatments
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
