University of Delaware Assistant Professor Erin Sparks wondered: what allows some corn stalks to stay standing while others are knocked to the ground? The answer is complicated, but Sparks is getting much closer to understanding these plant mechanics thanks to an engineering-based approach typically used on manmade structures proposed by the College of Engineering’s Monique Head.

As associate professor and associate chair of the Department of Civil and Environmental Engineering, Head has been using advanced technology and digital image correlation (DIC) to understand and estimate how a building or bridge deforms — how it bends or flexes under the weight of cars on it or in the face of a large storm — without ever having to touch the structure itself. To do that, she utilizes high-resolution cameras that capture an immense amount of data, not unlike the equipment used by professional surveyors. Just like old-school movies, the equipment is used to take an immense amount of photographs that can then be pieced together, analyzed using complex DIC algorithms, allowing Head to see how structures shift over time due to various influences, such as wind or weight.

It took a few years for Head and Sparks to connect the dots between their work. After four shared events outside of the classroom, including one encouraging young female students to explore futures in science, technology, engineering and math (STEM), and hearing each other use so many similar descriptions as they spoke about their work, they saw clearly that they shared much more common ground than just being science-minded colleagues at UD. Sparks’ questions about corn and Head’s work with bridges were almost exactly the same: whether they were looking at concrete or plant material, they were both trying to quantify the object’s structural stability.

“We realized we were trying to study the phenomenon of how or why things bend or flex,” Head said. “Moreso, we’ve done that with bridges. We wanted to see if we can do the same thing to quantify the response in corn and if we could use the same methodologies in a non-contact way.”

While the stakes may seem higher when someone is trying to pinpoint the weak points on a busy bridge so it doesn’t collapse, farmers also stand to lose a lot when an entire crop — their livelihood — is destroyed because the plants are broken or bent to the ground. And just as some bridge foundations may be difficult to reach, so are the underground root systems of plants like corn.

“People often think of plants as basically a rigid attachment to the ground and a stick,” said Sparks, who teaches plant molecular biology in UD’s College of Agriculture and Natural Resources. But that’s not the case at all, especially with corn plants, which have a complex above- and below-ground root system that is able to rotate and shift, she said.

“Dr. Head and her team, Shaymaa Obayes (doctoral student), Luke Timber (master's student), and David Bydalek (2020 graduate), were able to take measurements of what’s actually happening as plants bend and flex, and translate this information into models,” Sparks said. That modeling approach cuts back on the amount of time needed working directly with the plants in the field, and allows researchers to explore infinite combinations of variables to better understand why the corn behaves the way it does.

With Head an experienced, tenured professor and Sparks a newer, untenured faculty member, they teamed up in 2020 and pursued funding for their interdisciplinary, collaborative work through UD’s Research Foundation Strategic Initiatives grants, which provided $45,000 in funding to support one doctoral student pursuing this work in Head’s lab.

But when Shaymaa Khudhair Obayes, a civil engineering doctoral student, first heard about working with corn instead of bridges, she wasn’t so sure how it would pan out.

“My master’s was related to the design of bridges, and I expected I’d work on bridges as well as I pursued my Ph.D.,” Obayes said, admitting that shifting her focus to corn was quite difficult at first. “It's kind of like engineering from a different perspective.”

Applying what she knows about engineering theories and analysis to something new also boosted her confidence in her abilities as a professional, she said. Obayes already has a job in her home country, Iraq, but has many options for her future engineering career.

“At the end of my work, we learned we can apply all of the engineering theories to the corn and it works very well,” she said. “Now, if someone talks about the connection between agriculture and engineering, I already see the relationship between them and how we can use engineering to make improvements.”

A collaborative journal paper on their findings is submitted and expected to be published in the near future, Head said.

By using digital imaging, modeling and analysis tools, these researchers have been able to mimic how a corn plant’s stalk and root system could be represented with engineering mechanics, which Head said has not been done before with field measurements to support the analysis. From there, researchers can try to figure out what attributes caused a plant to stay upright or get knocked to the ground.