Image courtesy of Jordan Peccia.
Microbes are everywhere these days. Our understanding of microbial communities’ prevalence and function has expanded tremendously since the humble beginnings of science, when all microbes were assumed to be pathogenic. Recent discoveries suggest that these microscopic organisms could play crucial roles in tree nutrient cycling, disease resistance, growth, and possibly more.
According to Jordan Peccia, professor of Environmental Engineering at Yale, this branch of microbiology is relatively unexplored. “There has not been much interest in what’s inside the living wood of a tree,” Peccia said. Some studies have attempted to develop our understanding of microbial activity in trees, but sampling techniques of microbial communities have proved to be a significant barrier to discovery. Traditional sampling techniques are hindered by the physical resilience and composition of wood, which leads to a low microbial sample yield.
Stumped by these issues, Yale graduate students Wyatt Arnold (GSAS ’24) and Jonathan Gewirtzman (GSAS ’26) set out with their team to the Yale-Meyers Forest to devise the optimal strategy for sampling microbial communities in wood. After more than a year of sampling methane-cycling microbes, they identified the most effective method—a synthesis of old and new techniques. First, they collected a tree core with an instrument called an increment borer, which extracts a thin tube from the center of the tree. Next, they freeze-dried their sample, ground the wood into a fine powder, and formed a potent solution from which they extracted genetic material to analyze the microbial community.
“We don’t understand how microbes inside of trees help the trees, but we definitely know that they are there doing a function that has evolved along with the tree,” Peccia said. Assisted by this new methodology, scientists will now be better equipped to explore the function of microbial communities in trees.