Standing tall at Illinois State’s Horticulture Center is the castor bean plant, a fast-growing suckering shrub with dark-reddish purple leaves. It’s a beautiful plant. And it can also kill you.

The seeds from the castor bean plant are poisonous to people, animals and insects. That’s because the toxic protein in the castor bean is ricin. That may sound familiar, because even just one milligram of ricin can kill an adult human.

“That’s an awesome annual, but, you know, it’s pretty poisonous,” said Jessica Chambers ’93, coordinator at the Horticulture Center.

The center’s theme for 2012 is Gardens of Ill-Repute: Showcasing Wicked Plants and the Vile Acts They Commit. The goal, in part, is to bring attention to the fact that many of the plants in homes, landscapes and even parts of plants found in the foods we eat are poisonous.

The Horticulture Center marked the 2012 theme with a daylong series of events last week featuring author Amy Stewart, who wrote The New York Times best-seller Wicked Plants: The Weed that Killed Lincoln’s Mother and Other Botanical Atrocities, which inspired Chambers and the center’s staff. They’ve been working since Christmas on finding and displaying plants with a darker side.

“As the director of the center, it’s my job to show people plants and what a beautiful, fantastic world this is, and it was just a different way to show plants,” Chambers said. “It all came from that book.”

Stewart visited Illinois State’s Alumni Center to talk about her latest book, a follow-up called Wicked Bugs: The Louse that Conquered Napoleon’s Army.

She recounted several times when bugs have played a key role in changing the course of history or lead to someone’s bizarre death. In Napoleon’s case, the 1812 invasion of Russia was doomed for myriad reasons, including the prevalence of body lice among his troops. Unlike head lice, body lice can transfer disease, and “there were no Laundromats as they were moving through the Russian countryside,” Stewart said.

Body lice “are one of the reasons we’re not all speaking French right now,” she said.

She also tried to debunk the perception of bugs as mostly villainous. Most, she said, can’t hurt us at all.

“People are way too trusting of plants,” Stewart said. “With the insect world, it’s the exact opposite.”

Check out photos from the Horticulture Center’s Ill-Repute theme and Stewart’s visit on Illinois State’s Flickr account.

Ryan Denham can be reached at rmdenha@ilstu.edu.