Run outside for a moment and take a huge breath of air. You’ve just inhaled thousands of microorganisms: fungi, bacteria, and viruses. Virginia Tech plant pathology professor David Schmale wants to know where they come from.
Dr. Schmale did a presentation I attended a couple of months ago, and I was fascinated by his work. The sexy part of what he does is the specialized equipment he uses to collect his samples, things like unmanned aerial vehicles (UAVs) – what we call drones – and other unmanned systems such as boats and underwater vehicles. But what I found fascinating is the science itself and how the invisible, ancient source of energy, the wind, is an endless conduit for all manner of infinitesimally little things. So I invited myself to visit with him in his office in Latham Hall to learn more.
He was hired as a plant pathologist (“Pathology” means disease.), but now, “I really am an aerobiologist. Aerobiology is the study of the flow of life in the atmosphere.”
David is a big, strong man who looks more like an NFL linebacker than a science professor (He likes to lift heavy things and can bench press 365 pounds.). “Some of the microorganisms are dead; some are living. ‘Micro’ means it’s microscopic. ‘Organism’ implies that it is a living agent, or was. These microorganisms fly along what we like to call ‘highways in the sky.’”
He said that plants of all sizes can serve as sources of microorganisms and microscopic propagules. For example, flowers and trees can produce pollen. Pollen is an agent whereby a plant is able to relocate elsewhere and reproduce. And bacteria and fungal spores can hitch a ride on the pollen grains.
“We are interested in the transport of microorganisms from one place to the next. We think about plant diseases and causal agents of plant diseases that can move through the atmosphere over some distance from infected plants. Much of our foundational work is understanding this transport.
“Consider a grower of some agricultural crop. You may be worried about a disease that you know has infected neighboring fields. Perhaps your neighboring farmer has incurred a loss due to a devastating pathogen or an infection of his crop. You want to plan for its arrival. By understanding when and how the pathogen might be traveling to your crop, you can make informed decisions about how to manage the disease, such as the appropriate timing of chemical treatments such as fungicides.”
He said the movement of stuff in the air is partly controlled by weather and wind. Major atmospheric phenomena like hurricanes shuffle things in the air over long distances. The higher things are lifted, typically the farther they will be transported. On the other hand, microorganisms that get transported at higher altitudes often don’t survive due to UV radiation and desiccation (drying out).
During storms, dust particles, fine sand and similar inert particulates, are entrained into winds and taken aloft. “During the hurricane season, dust from Africa can even make it to Virginia.”
I asked how he came to develop his interest in science. He said his parents were both teachers, and he gravitated towards academics and learning. The kind of guy who seems like he’s good at almost anything he tried, he was a singer and dancer as child and considered going to college to on a vocal scholarship. He ultimately enrolled at the University of California in Davis to study pre-med, thinking he’d become a medical doctor. He took a course in what then was called botany. “I was so intrigued that plants could get sick.”
He got his doctorate at Cornell University in Ithaca, New York and was hired at Tech where his wife was also hired as a mathematics professor. He teaches, does scientific studies, and obtains research funding. “I see my role here at Virginia Tech is to create opportunities for others. In doing so, we create opportunities together for really great science. My career has been in attracting talent and having the talent frame where the program should go: the tools, techniques, and questions we need to be addressing.”
Tech’s media office often focuses on high-impact, high-visibility research. He has enjoyed this press for many of his multimillion dollar federal grants. But he also maintains a focus on the smaller grants that can still produce significant scientific breakthroughs. “There are many smaller, less publicized, success stories. They deserve some press, too!”
He acknowledges the potential for terrible things to happen, either naturally or by bio-terrorism. But he remains optimistic about the future. “We are moving into a technologically savvy world where sensors are monitoring our daily lives, things like watches that will monitor our heart rate and remind us to take our medicines. It’s an exciting time when sensing modalities can improve our quality of life.”
Michael Abraham is a businessman and author. He was raised in Christiansburg and lives in Blacksburg.