Photo By: Photo by Dominique Belcher
Wood rot can be a homeowner's worst nightmare. Spotting signs of decay often means significant structural damage has already occurred. But what if you could detect wood rot before it is visible?
Researchers in the Mississippi State University Forest and Wildlife Research Center are teaming with the United States Department of Agriculture Forest Products Laboratory to identify the earliest presence of brown rot fungus in southern yellow pine—a widely used source of lumber in the U.S. construction market.
Landon Greene, a sustainable bioproducts graduate student who earned his bachelor's degree in forestry, has assisted Dr. Tamara Franca, assistant professor in sustainable bioproducts, with her ongoing research to identify the presence of brown rot fungus in southern yellow pine at its earliest stages and examine its impact on the wood's integrity. Currently, when brown rot fungus is detected on cross-laminated timber, major structural damage has occurred, resulting in the replacement of lumber, which is expensive and labor-intensive.
"If you can see decay in the wood, the damage has already been done," Franca said. "Our goal is to try to identify incipient decay, when the fungus is just taking a foothold, before anyone can see it."
Greene studied samples over a 12-week period, testing the strength of experimental boards exposed to the fungus and comparing them to the control sample. The study also involved extensive soil sampling to test for the fungus, with Greene collecting more than 400 samples. This research points out the need for early testing to prevent future damage to structures built with southern yellow pine lumber.
"At these early stages, we can't see the decay with the naked eye, but if the wood is losing two to ten percent of its mass, that loss affects its mechanical properties," he said. "If we can test early, we can replace the few affected boards—keeping the rest of the original boards in service for as long as possible and the structure of the building intact."
According to a USDA report, in the first half of 2022, U.S. repair and renovation construction expenditures were $347.2 billion. Residential repair and renovation currently use more wood products than new housing construction.
"Brown rot fungi consumes cellulose that provides wood fibers their tensile strength," said Dr. Rubin Shmulsky, head of the Department of Sustainable Bioproducts and FWRC scientist. "This action creates a distinctive cubical pattern in the wood, turns the wood brown, and reduces its structural capacity."
Brown rot spores are everywhere and spread quickly under favorable conditions, often causing severe damage. An early detection system could be a game changer for homeowners who bear the expense of replacing decayed wood, Shmulsky added.
For Greene, who graduated in May, the hands-on learning experience has prepared him for success in the workforce.
"I have a broad range of skills that will prepare me for a wide variety of jobs," he said. "I would like to work in some aspect of quality control management—treating and testing products and making sure they meet industry standards."
With Greene on the job, armed with his MSU research, he will make a difference in extending the use of wood products.
