The Brazilian Pepper Killer

Brazilian Pepper has long existed as an invasive nuisance. Classified as a ‘noxious weed’ by the FWC, prohibited for sale and transport by the Florida Department of Environmental Protection, and covering over 700,000 acres in 30 Florida Counties, Brazilian Pepper is synonymous with pythons, hurricanes, and development when it comes to the threat of Florida’s disappearing habitats.

That was the case until two months ago, when a high school on an MIT grant designed a robot capable of turning this omnipotent shrub into fertilizer.

Seven members of Pembroke Pines Charter High School were selected for the 2025-26 Lemelson-MIT InvenTeams program, an initiative aimed at supporting students in creating tech-based solutions for real-world problems. After a journey in the Everglades, they found their primary antagonist.

“You see Brazilian Pepper everywhere; it took over the Everglades,” said Valentina Glen, communications lead of the team. “We conducted field research with Professor Jed Redwine from FIU, and the Rangers had just done a controlled burn of 5,000 acres. But they still had to manually remove each root.”

“We wanted to make that process easier.”

Brazilian Pepper’s roots are notorious—they run thin and deep. Burrowing a minimum of 12 inches underground, if even one-quarter of an inch in diameter is left, the shrub will regrow. Which isn’t a problem for “Radix,” the remote-controlled robot that turns its stems into smoothies.

“We have a mechanism which drills directly into the stem or stump of the tree, so that the majority of the vascular tissue is removed,” said Umer Qureshi, who also won the L-MIT grant last year. “It won't be able to bud from the main stem, and whatever nutrients are left won't allow the Brazilian Pepper to grow again.”

This mechanism, dubbed ‘Radix’—meaning both “root” in Latin and sounding extremely cool—is a remote-controlled robot that slices through the thin trunk of the potentially 30-foot-tall plant. Despite a complicated root system, Radix digs through the stems and roots, mimicking what harmful herbicides accomplish without posing the same danger to nearby fauna.

“We realized that herbicides work by blocking the stem structures, xylem, and phloem,” said Qureshi. “So if we can do the same thing, but instead mechanically remove the xylem phloem, it would be better for the environment.”

Though unlike the herbicide, Radix is also capable of destroying the plant in multiple directions.

“The mechanism has opposable arms with four axes (plural of axis) that pose in different directions before drilling into the stem,” said Qureshi. “So regardless of the angle or entanglement, the tree size or consistency, we’re able to remove it.”

Radix doesn’t stop at remote-controlled capabilities; the team is researching an automation process that allows the weed-whacker to seek and destroy Brazilian Pepper automatically.

“For the initial testing portion, we wanted to have it remote-controlled so that we can capture data while not accidentally removing native species at the same time,” said Qureshi. “But we have the determination to make it more autonomous later on.”

Radix is most effective on fully grown Brazilian Pepper when the roots are the thickest. The team also intends for the robot to be utilized during winter, when the plant isn’t in bloom. This allows for remote-control removal of the plant with no additional human input or clean-up.

“It's best when it's fully grown, because in its early stages the Brazilian pepper is more shrub-like,” said Steve Jacobs, one of the students on the L-MIT team. “Our removal method isn't as effective on new growth since it's difficult to cut down something like leaves.”

Another infamous invasive species, the Rosary Pea, also dominates most Florida parks and gardens. Its roots burrow deep and regrow unless immense effort is expended in excavating its bio-matter. It produces abrin, a poison similar to ricin, where only 0.000015 percent in body weight ratio is enough to cause death.

That amount is contained in even a single seed.

“Right now we just want to focus on the Brazilian Pepper tree, but we do intend to focus on other plants in the future,” said Qureshi. “The only issue is that we need to do more research on those plants directly and change up our mechanisms depending on the plant structures.”

The team is hoping that with the help of the National Park Service and community outreach, they can begin live test runs and refine their invention. At the moment, Radix remains a prototype.

“We also reached out to Vista View Park, and we're trying to experiment on the Brazilian peppers there,” captain of the swim team and sophomore scientist John Abohasen said. “When our invention is ready to start testing, we plan on starting to remove live Brazilian Pepper.”

Brazilian Pepper is a persistent issue in Spain, Australia, California, and South Africa. The team holds hope that Radix could very well mitigate the species globally, especially where it is considerably more dangerous. It has the potential for removing other invasive species and restoring hundreds of thousands of acres of South Florida.

“We hope that this machine will be able to take care of these invasive species everywhere,” said Abohasen. “Go big or go home.”

The L-MIT team will post updates on their Instagram, @ppchslmit.